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SCXG-SVX01B-EN

Installation, Operation, &

Maintenance

IntelliPak

Commercial Self-Contained

Modular Series, 20-35 tons

“JO” and later design sequence

Models:

SCWG -020, -025, -030, -032, -035

SIWG -020, -025, -030, -032, -035

SCRG -020, -025, -030, -032

SIRG -020, -025, -030, -032

March 2008

TM

© 2008 Trane All rights reserved SCXG-SVX01B-EN

About This Manual

Literature Change History

Use this manual for commercial self-

contained models SCWG, SIWG, SCRG,

and SIRG. This is the second or “B”

revision of this manual. It provides

specific installation, operation, and

maintenance, instructions for “JO” and

later design sequences. The “JO” design

sequence includes the addition of 407c

refrigerant option and VFD change from

Square D 58 to the Trane TR-1. Also, this

literature contains changes in the filter

sizes and quantities for some unit sizes.

For previous design sequences, contact

your local Trane representative.

Hazard Identification

Warnings and cautions appear at

appropriate sections throughout this

manual. Read these carefully.





WARNING

Indicates a potentially hazardous

situation, which could result in

death or serious injury if not

avoided.





CAUTION

Indicates a potentially hazardous

situation, which may result in

minor or moderate injury if not

avoided. Also, it may alert against

unsafe practices.

NOTICE

Indicates a situation that may result in

equipment or property-damage-only

accidents.





WARNING

Grounding Required!

Follow proper local and state electrical

code on requirements for grounding.

Failure to follow code could result in

death or serious injury.

Sample Warnings and Cautions





WARNING

Hazardous Voltage w/Capacitors!

Disconnect all electric power, including

remote disconnects before servicing.

Follow proper lockout/tagout proce-

dures to ensure the power cannot be

inadvertently energized. For variable

frequency drives or other energy storing

components provided by Trane or others,

refer to the appropriate manufacturer’s

literature for allowable waiting periods

for discharge of capacitors. Verify with an

appropriate voltmeter that all capacitors

have discharged. Failure to disconnect

power and discharge capacitors before

servicing could result in death or serious

injury.

Note: For additional information regard-

ing the safe discharge of capacitors, see

PROD-SVB06A-EN or PROD-SVB06A-FR.

NOTICE

Use Copper Conductors Only!

Unit terminals are not designed to

accept other type conductors. Failure to

use copper conductors may result in

equipment damage.

Common HVAC Acronyms

For convenience, a number of acronyms

and abbreviations are used throughout

this manual. These acronyms are

alphabetically listed and defined below.

BAS = Building automation systems

CFM = Cubic-feet-per-minute

CKT. = Circuit

CV = Constant volume

CW = Clockwise

CCW = Counterclockwise

E/A = Exhaust air

ECEM = Exhaust/comparative enthalpy

module

F/A = Fresh air

GBAS = Generic building automation

system

HGBP = Hot gas bypass

HI = Human Interface

HVAC = Heating, ventilation and air

conditioning

IGV = Inlet guide vanes

I/O = Inputs/outputs

IOD= Installation/owner/

diagnosticmanual

IPC = Interprocessor communications

IPCB = Interprocessor communications

bridge

LH = Left-hand

MCM = Multiple compressor module

MWU = Morning warmup

NSB = Night setback

O/A = Outside air

psig = Pounds-per-square-inch, gauge

pressure

R/A = Return air

RH = Right-hand

RPM = Revolutions-per-minute

RTM = Rooftop module

S/A = Supply air

SCM = Single circuit module

SZ = Single-zone (unit airflow)

LCI-I communications module

UCM = Unit control modules

VAV = Variable air volume

VCM = Ventilation control module

VOM = Ventilation override module

w.c. = Water column

WSM = Waterside module

ZSM = Zone sensor module

Special Note on Refrigeration

Emissions

World environmental scientists have

concluded that ozone in our upper

atmosphere is being reduced due to the

release of CFC fully halogenated

compounds.

Trane urges all HVAC service personnel

to make every effort to prevent any

refrigerant emissions while installing,

operating, or servicing equipment.

Always conserve refrigerants for

continued use.

Introduction

SCXG-SVX01B-EN 3

Cross reference to related publications/information:

• Product Catalog, PKG-PRC003-EN, Modular Series Commercial Self-Contained

• IntelliPak• Self-Contained Programming Guide, PKG-SVP01B-EN

• Remote Air-Cool-Condenser Installation, Owner, and Diagnostic Manual, CXRC-

SVX01B-EN

Installation …………………………........…....…6

general information …………………………………………6

pre-installation considerations… …………………………11

dimensions & weights ………………………………...…19

mechanical specifications …………………………………30

electrical requirements ……………………………………33

pre-startup requirements …………………………………35

programming ………………………………….……………57

startup …………………………………………………….…67

Operation ………………………………………70

general information ………………………………………70

sequence of operation ………………………………….…84

Maintenance ……………………………………91

maintenance procedures ………………………………92

troubleshooting ………………………………………..…105

diagnostics ………………………………………………..106

Contents

4SCXG-SVX01B-EN

Features and

Benefits

Refrigerant Handling

Procedures

Environmental Accountability Policy

Trane urges that all HVAC servicers to

make every effort to eliminate, if possible,

or vigorously reduce the emission of CFC,

HCFC, and HFC refrigerants to the

atmosphere. Always act in a responsible

manner to conserve refrigerants for

continued usage even when acceptable

alternatives are available.

Recover and Recycle Refrigerants

Never release refrigerant to the

atmosphere! Always recover and/or

recycle refrigerant for reuse,

reprocessing (reclaimed), or properly

dispose if removing from equipment.

Always determine the recycle or reclaim

requirements of the refrigerant before

beginning the recovery procedure.

Obtain a chemical analysis of the

refrigerant if necessary. Questions about

recovered refrigerant and acceptable

refrigerant quality standards are

addressed in ARI Standard 700.

Refrigerant Handling and Safety

Consult the manufacturer’s material

safety data sheet (MSDS) for information

on refrigerant handling to fully

understand health, safety, storage,

handling, and disposal requirements. Use

the approved containment vessels and

refer to appropriate safety standards.

Comply with all applicable transportation

standards when shipping refrigerant

containers.

Service Equipment and Procedures

To minimize refrigerant emissions while

recovering refrigerant, use the

manufacturer’s recommended recycling

equipment per the MSDS. Use

equipment and methods which will pull

the lowest possible system vacuum while

recovering and condensing refrigerant.

Equipment capable of pulling a vacuum of

less than 1,000 microns of mercury is

recommended.

Do not open the unit to the atmosphere

for service work until refrigerant is fully

removed/recovered. When leak-testing

with trace refrigerant and nitrogen, use

HCFC-22 (R-22) rather than CFC-12 (R-

12) or any other fully-halogenated

refrigerant . Be aware of any new leak

test methods which may eliminate

refrigerants as a trace gas. Perform

evacuation prior to charging with a

vacuum pump capable of pulling a

vacuum of 1,000 microns of mercury or

less. Let the unit stand for 12 hours and

with the vacuum not rising above 2,500

microns of mercury.

A rise above 2,500 microns of mercury

indicates a leak test is required to locate

and repair any leaks. A leak test is

required on any repaired area.

Charge refrigerant into the equipment

only after equipment does not leak or

contain moisture. Reference proper

refrigerant charge requirements in the

maintenance section of this manual to

ensure efficient machine operation.

When charging is complete, purge or

drain charging lines into an approved

refrigerant container. Seal all used

refrigerant containers with approved

closure devices to prevent unused

refrigerant from escaping to the atmo-

sphere. Take extra care to properly

maintain all service equipment directly

supporting refrigerant service work such

as gauges, hoses, vacuum pumps, and

recycling equipment .

When cleaning system components or

parts, avoid using CFC-11 (R-11) or CFC-

113 (R-113). Use only cleaning-solvents

that do not have ozone depletion factors.

Properly dispose of used materials.

Refrigeration system cleanup methods

using filters and driers are preferred.

Keep abreast of unit enhancements,

conversion refrigerants, compatible

parts, and manufacturer’s recommenda-

tions that will reduce refrigerant emis-

sions and increase equipment operating

efficiencies.

SCXG-SVX01B-EN 5

Figure I-GI-1. IntelliPak

®

commercial self-contained Modular Series unit.

Modular Series Self-Contained

Unit Components

Commercial self contained units are

complete HVAC systems used in floor-by-

floor applications. Units are easy to install

because they feature a single point

power connection, factory installed and

tested controls, single water point

connection, factory installed options, and

an internally trapped drain connection.

Modular self-contained units can ship as

split-apart units for installation ease. Split-

apart units ship with a dry nitrogen

charge and require field refrigerant

charging.

Units consist of multiple compressors,

water-cooled condensers (water-cooled

units only), an evaporator coil, dual

forward curved fans, and control panel.

Air-cooled units require a remote air-

cooled condenser, model CXRC. The

hermetically sealed 3-D scroll

compressor motors utilize internal motor

protection and time delays to prevent

excessive cycling. Unit controls are either

an electromechanical thermostat or

microprocessor controls on the IntelliPak

unit. See Figure I-GI-1 for a typical unit.

The hermetically sealed 3-D scroll

compressor motors utilize internal motor

protection and time delays to prevent

excessive cycling.

The water-cooled condensers are shell

and tube type with an internal subcooler.

Condensers are available as mechani-

cally or chemically cleanable. The

evaporator fan is double width, double

inlet and forward curved with a fixed

pitch belt drive assembly. Frequency

drives or inlet guide vanes are optional.

Motor options include open drip proof,

high efficiency, TEFC, or mill and chem

spec.

All water-cooled units ship with a full

refrigerant and oil charge. Air-cooled

units ship with oil and a dry nitrogen

holding charge and require field-piping

refrigerant connections to the air cooled

condensing unit. Also, air-cooled units

have two refrigerant circuits. Water-

cooled units have four refrigerant circuits;

which include a filter drier, pressure relief

valve, liquid line service valve, sight glass/

moisture indicator, thermal expansion

valve with a sensing bulb and external

equalizing line, discharge line shrader

valve, a suction line shrader valve, and

high and low pressure cutout switches.

Water-cooled units also include a liquid

line service valve for each circuit.

For more detailed information, see the

Owner’s section of this manual.

Features and

Benefits

6SCXG-SVX01B-EN

Installation

Control Options

Units may be ordered with either

conventional thermostat interface or

IntelliPakTM Direct Digital Control (DDC).

IntelliPakTM controls include a Human

Interface (HI) panel with two line by forty

(40) character clear English display for

easy operator interface to unit setup and

control parameters. All basic setup

parameters are preset from the factory.

Human Interface Panel

The HI is unit mounted and accessible

without opening the unit’s front panel. It

allows easy setpoint adjustment using

the HI keypad. In addition, the HI displays

all unit operating parameters and

conditions in a clear language display,

which can be configured for either

English, French, or Spanish.

The optional remote human interface

(RHI) will control up to four self-contained

units, each containing an interprocessor

communications bridge (IPCB). It has all

the same features as the unit-mounted HI

except for the service mode.

For more information on setpoint defaults

and ranges and unit programming, see

the

IntelliPak Self-Contained Program-

ming Guide, PKG-SVP01B-EN

. A copy

ships with each unit.

IntelliPakTM DDC Control

IntelliPakTM DDC Control provides “smart”

unit control with safety features and

control relays for pumps, dampers, etc.

The Modular Series IntelliPak self-

contained unit is controlled by a

microelectronic control system that

consists of a network of modules. These

modules are referred to as unit control

modules (UCM). In this manual, the

acronym UCM refers to the entire control

general

information

system network.

These modules perform specific unit

functions using proportional/integral

control algorithms. They are mounted in

the unit control panel and are factory

wired to their respective internal compo-

nents. Each module receives and

interprets information from other unit

modules, sensors, remote panels, and

customer binary contacts to satisfy the

applicable request; i.e., economizing,

mechanical cooling, heating, ventilation.

See the Operation section of this manual

for a detailed description of each

module’s function.

Optional Controls

Optional controls include a disconnect

switch, dirty filter switch, water flow

switch (water-cooled only), supply air

temperature reset, or external setpoint

inputs. Daytime heating is available on

units with electric, steam, or hot water

heat control options. Morning warmup

operation is available on all units.

The static pressure probe, zone night

heat/morning warmup, supply air

temperature reset sensor options ship

separate inside the unit control panel for

field installation. For more detailed

information on the unit control options,

see the Owner’s section of this manual.

Unit Nameplate

The unit nameplate identifies the unit

model number, appropriate service

literature, and wiring diagram numbers. It

is mounted on the left end of the unit

control panel.

SCXG-SVX01B-EN 7

Model

Number

Description

Model Number Description

Each IntelliPak self-contained unit has a multiple character model number unique to that unit. To determine a unit’s specific options,

reference the model number on the unit nameplate using the model number explanation below.

SCWG

S C W G N 20 4 2 JO A B 2 10 085 B A 1 0 1 0 A A C F A 1 1 0 T 2 0

1 2 3 4 5 67 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

Digit 1 - Unit Model

S = Self Contained

Digit 2 - Unit Type

C = Commercial

I = Industrial

Digit 3 - Condenser Medium

W = Water-Cooled

R = Remote Air-Cooled

Digit 4 - Development Sequence

G = Modular Series

Digit 5 - Refrigerant Circuit Configuration

N = Independent, R-22 Refrigerant

R = Independent, 407C Refigerant

Digit 6, 7 - Unit Nominal Capacity

2 0 = 20 Tons (Water or Air Cooled)

2 5 = 25 Tons (Water or Air Cooled)

30 = 30 Tons (Water Cooled Only)

32 = 32 Tons (Air Cooled Only)

35 = 35 Tons (Water Cooled Only)

Digit 8 - Unit Voltage

6 = 200 Volt/60 Hz/3 ph

4 = 460 Volt/60 Hz/3 ph

5 = 575 Volt/60 Hz/3 ph

Digit 9 - Air Volume/Temp Control

1 = I-Pak & IGV and Supply Air Temp

Ctrl

2 = I-Pak & VFD and Supply Air

Temp Ctrl

3 = I-Pak & VFD w/ Bypass and

Supply Air Temp Ctrl

4 = I-Pak w/o Vol. CTRL, w/ Zone Temp

Cool

5 = I-Pak w/o Vol. CTRL, w/ Zone Temp

Heat/Cool

6 = I-Pak w/o Vol. CTRL, w/ Supply Air

Temp Ctrl

8 = Thermostat Interface

Digit 10, 11 - Design Sequence

JO= “J” Design

Digit 12 - Unit Construction

A = Vertical Discharge

B = Vertical Discharge with Double Wall

C = Horizontal Discharge

D = Horizontal Discharge w/ Double

Wall

E = Vertical Discharge, Ship Separate

F = Vertical Discharge w/ Double Wall,

Ship Separate

G = Horizontal Discharge, Ship Separate

H = Horizontal Discharge w/ Double

Wall, Ship Separate

Digit 13 - Plenum Type

B = Std Plenum w/ Factory Cut Holes

C = Low Plenum w/ Factory Cut Holes

E = Std Plenum w/ Field Cut Holes

F = Low Plenum w/ Field Cut Holes

H = Std Plenum Double Wall (Perf)

w/ Field Cut Holes

J = Low Plenum Double Wall (Perf)

w/ Field Cut Holes

L = Std. Plenum w/Factory Cut Holes,

Ship Separate

M = Low Plenum with Factory Cut

Holes, Ship Separate

P = Std Plenum w/ Field Cut Holes, Ship

Separate

R = Low Plenum w/ Field Cut Holes,

Ship Separate

U = Std Plenum Double Wall (Perf) w/

Field Cut Holes, Ship Separate

V = Low Plenum Double Wall (Perf) w/

Field Cut Holes, Ship Separate

0 = Without Plenum

Digit 14 - Motor Type

1 = Std. Efficiency ODP

2 = Premium Eff. ODP

3 = Std. Efficiency Totally Enclosed

Digit 15, 16 - Motor HP

05 = 5 HP Motor

07 = 7.5 HP Motor

10 = 10 HP Motor

15 = 15 HP Motor

20 = 20 HP Motor

25 = 25 HP Motor

Digit 17, 18, 19 - Fan RPM

085 = 850 rpm

090 = 900 rpm

095 = 950 rpm

100 = 1000 rpm

105 = 1050 rpm

110 = 1100 rpm

115 = 1150 rpm

120 = 1200 rpm

125 = 1250 rpm

130 = 1300 rpm

135 = 1350 rpm

140 = 1400 rpm

145 = 1450 rpm

150 = 1500 rpm

155 = 1550 rpm

160 = 1600 rpm

165 = 1650 rpm

170 = 1700 rpm

175 = 1750 rpm

180 = 1800 rpm

185 = 1850 rpm

Digit 20 - Heating Type

A = Steam Coil, LH

B = Hot Water Coil, LH

C = Electric Heat, 1 Stage

F = Hydronic Heat Ctrl Interface

G = Elec. Heat Ctrl Interface, 1 stage

K = Steam Coil Ship Separate, LH

L = Hot Water Coil Ship Separate, LH

M = Steam Coil, RH

N = Hot Water Coil, RH

P = Steam Coil Ship Separate, RH

R = Hot Water Coil Ship Separate, RH

T = Hi-cap. hot water coil, LH

U = Hi-cap, hot water coil LH,

Ship Seperate

V = Hi-cap. hot water coil, RH

W = Hi-cap. hot water coil, RH,

Ship Seperate

0 = None

Digit 21 - Unit Isolators

A = Isopads

B = Spring Isolators

0 = None

8SCXG-SVX01B-EN

Model

Number

Description SCWG

Digit 22 - Unit Finish

1 = Paint - Executive Beige

2 = Protective Coating

3 = Protective Coating w/ Finish Coat

Digit 23

0 = None

Digit 24 - Unit Connection

1 = Disconnect Switch

2 = Terminal Block

3 = Dual Point Power

Digit 25 - Industrial Options

A = Protective Coated Evaporator Coil

B = Silver Solder

C = Stainless Steel Screws

D = A and B

E = A and C

F = B and C

G = A, B and C

0 = None

Digit 26 - Drain Pan Type

A = Galvanized Sloped

B = Stainless Steel Sloped

Digit 27 - Waterside Economizer

A = Mechanical Clean Full Cap. (4-row)

B = Mechanical Clean Low Cap. (2-row)

C = Chemical Clean Full Cap. (4-row)

D = Chemical Clean Low Cap. (2-row)

E = Mechanical Clean Full Capacity

(4-row) Ship Separate

F = Mechanical Clean Low Capacity

(2-row) Ship Separate

G = Chemical Clean Full Capacity

(4-row) Ship Separate

H = Chemical Clean Low Capacity

(2-row) Ship Separate

0 = None

Digit 28 - Ventilation Control

B = Airside Econ w/ Traq™ Damper

(Top O/A Inlet)

C = Airside Econ w/ Standard

Dampers (Top O/A Inlet)

E = Airside Econ w/ Traq™ Damper and

Comparative Enthalpy

(Top O/A Inlet)

F = Airside Econ w/ Std Dampers and

Comparative Enthalpy (Top O/A

Inlet)

G = Traq Damper Ventilation Interface

H = Ventilation For 2 Pos. Cntrl Interface

0 = None

Digit 29 - Water Piping

A = Right Hand Condenser Connection

B = Left Hand Condenser Connection

C = Right Hand Basic Piping

D = Left Hand Basic Piping

E = Right Hand Intermediate Piping

F = Left Hand Intermediate Piping

J = Right Hand Basic w/ Flow Switch

K = Left Hand Basic w/ Flow Switch

L = Right Hand Intermediate

w/ Flow Switch

M = Left Hand Intermediate

w/ Flow Switch

0 = None

Digit 30 - Condenser Tube Type

A = Standard Condenser Tubes

B = 90/10 CuNi Condenser Tubes

0 = None

Digit 31 - Compressor Service Valves

1 = With Service Valves

0 = None

Digit 32 - Miscellaneous System Control

1 = Timeclock

2 = Interface for Remote HI

3 = Dirty Filter Switch

4 = 1 and 2

5 = 1 and 3

6 = 2 and 3

7 = 1, 2, and 3

0 = None

Digit 33 - Control Interface Options

A = Generic BAS Module (GBAS)

B = Ventilation Override Module (VOM)

D = Remote Human Interface (RHI)

G = GBAS and VOM

H = GBAS and RHI

J = VOM and RHI

M = GBAS, VOM, and RHI

0 = None

1 = Tracer/LCI-I (COMM5) interface

module

2 = Tracer/LCI-I and GBAS

3 = Tracer/LCI-I and VOM

4 = Tracer/LCI-I and RHI

5 = Tracer/LCI-I, GBAS and VOM

6 = Tracer/LCI-I, GBAS and RHI

7 = Tracer/LCI-I, VOM and RHI

8 = Tracer/LCI-I, GBAS, VOM and RHI

Digit 34 - Agency

T = UL Agency Listing

0 = None

Digit 35 - Filter Type

1 = 2-inch Construction Throwaway

2 = 2-inch Med Eff. Throwaway

Digit 36 - Miscellaneous Control Option

A = Low Entering Air Temp. Protect

Device (LEATPD)

B = High Duct Temp T-Stat

C = Plenum High Static Switch

D = Kit for Heat Mode Output (w/t’stat)

E = A and B

F = A and C

G = B and C

H = A, B, and C

0 = None

SCXG-SVX01B-EN 9

P S W G S A 1 1 0 JO

1 2 3 4 5 6 7 8 9 10 11

Self-Contained Ship-With Accessory Model Number Description

Digit 1 - Parts/Accessories

P = Parts/Accessories

Digit 2 - Unit Model

S= Self-Contained

Digit 3 - Shipment

W = With Unit

Digit 4 - Development Sequence

F = Signature Series

G = Modular Series

Digit 5 - Sensors and Other Accessories

S = Sensors

Digit 6 - Sensors and Thermostats (field

installed)

A = BAYSENS077 - Zone Temp Only (C V

and VAV)

B = BAYSENS073 - Zone Temp with

Timed Override Button (CV and VAV)

C = BAYSENS074 - Zone Temp with

Timed Override Button, Setpoint Dial

(CV and VAV)

D = BAYSENS023 - Remote Min. Position

Potentiometer Control (OA Damper)

E = BAYSENS108 - CV Zone Sensor-dual

setpoint, man/auto changeover

F = BAYSENS110 - CV Zone Sensor-dual

setpoint, man/auto changeover w,

indicator lights

G = BAYSENS019 - CV Programmable

Night Setback Sensor

H = BAYSENS021 - VAV Zone Sensor with

Indicator Lights

J = BAYSENS020 - VAV Programmable

Night Setback Sensor

K = Remote Sensor Kit

L = Outside Air Temperature Sensor Kit

M = Outside Air Humidity Sensor Kit

N = BAYSTAT010 - 2 Heat/2 Cool

Thermostat

P = BAYSTAT037A - 2 Heat/2 Cool

Programmable Thermostat

0 = None

Model

Number

Description PSWG

Digit 7 - Mixed Air Temperature Protec-

tion Kit (field installed)

1 = Mixed Air Temperature Protection Kit

0 = None

Digit 8 - Carbon Dioxide Sensor (field

installed)

1 = Carbon Dioxide Sensor Kit

0 = None

Digit 9 - Future Option

0 = None

Digit 10, 11 - Design Sequence

J0 = J Design

10 SCXG-SVX01B-EN

Model

Number

Description PSWG

“After-Shipment” Accessory Model Number

P S A G W N 20 4 ** 1 10 0 0 0 1 0 1 0 1 0 1 0 0 1 1 0 0 0 0 0 L 1 0 0 7 0 0

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

Digit 1 - Parts/Accessories

P = Parts/Accessories

Digit 2 - Unit Model

S= Self-Contained

Digit 3 - Shipment

A = After Unit

Digit 4 - Development Sequence

F = Signature Series

G = Modular Series

Digit 5 - Condenser Medium

W = Water Cooled

R = remote Air Cooled

Digit 6 - Refrigerant Circuit Configuration

N = Independent (Water-Cooled)

M = Manifolded (Air-Cooled)

Digits 7, 8 - Unit Nominal Capacity

20 = 20 Tons (Water or Air)

22 = 22 Tons (Water Only)

25 = 25 Tons (Water or Air)

29 = 29 Tons (Water or Air)

30 = 30 Tons (Air Only)

32 = 32 Tons (Water Only)

35 = 35 Tons (Water or Air)

38 = 38 Tons (Water Only)

40 = 40 Tons (Air Only)

42 = 42 Tons (Water Only)

46 = 46 Tons (Water Only)

50 = 50 Tons (Air Only)

52 = 52 Tons (Water Only)

58 = 58 Tons (Water Only)

60 = 60 Tons (Air Only)

65 = 65 Tons (Water Only)

72 = 72 Tons (Water Only)

80 = 80 Tons (Water Only)

Digit 9 - Unit Voltage

6 = 200 Volt/60 Hz/3 ph

4 = 460 Volt/60 Hz/3 ph

5 = 575 Volt/60 Hz/3 ph

0 = Not Defined

Digits 10, 11 - Design Sequence

** = Factory Assigned

Digit 12 - Unit Power Connection

1 = Single Point Power

2 = Dual Point Power

0 = Not Defined

Digit 13, 14 - Motor HP

05 = 5 HP Motor

07 = 7.5 HP Motor

10 = 10 HP Motor

15 = 15 HP Motor

20 = 20 HP Motor

25 = 25 HP Motor

30 = 30 HP Motor

40 = 40 HP Motor

50 = 50 HP Motor (460V & 575V Only)

0 = Not Defined

Digit 15 - Exhaust/Comparative Enthalpy

Module (Field Installed)

1 = ECEM Kit

0 = None

Digit 16 - Generic BAS Module

1 = GBAS 0-5 VDC Kit

0 = None

Digit 17 - Heat Module

1 = Electric Heat Module Kit

2 = Hydronic Heat Module Kit

0 = None

Digit 18 - Remote Human Interface and

IPCB

1 = Remote Human Interface Panel Kit

(RHI Only)

2 = Interprocessor Communications

Module Kit (IPCB Only)

3 = RHI and IPCB Kit

0 = None

Digit 19 - LonTalk Communications

Interface Kit (LCI)

2 = Tracer/LCI-I Comm Interface Kit

0 = None

Digit 20 - Ventilation Override Module Kit

(VOM)

1 = VOM Kit

0 = None

Digit 21 - Sensors and Thermostats

A = BAYSENS077 - Zone Temp Only (CV

and VAV)

B = BAYSENS073 - Zone Temp with

Timed Override Button (CV and VAV)

C = BAYSENS074 - Zone Temp with

Timed Override Button, Setpoint Dial

(CV and VAV)

E = BAYSENS108 - CV Zone Sensor-dual

setpoint, man/auto changeover

F = BAYSENS110 - CV Zone Sensor-dual

setpoint, man/auto changeover w,

indicator lights

G = BAYSENS019 - CV Programmable

Night Setback Sensor

H = BAYSENS021 - VAV Zone Sensor

with Indicator Lights

J = BAYSENS020 - VAV Programmable

Night Setback Sensor

K = Remote Sensor Kit

L = Outside Air Temperature Sensor Kit

M = Outside Air Humidity Sensor Kit

0 = None

Digit 22 - Low Entering Air Temperature

Protection Device

1 = Low Entering Air Temperature

Protection Device Kit

0 = None

Digit 23 - High Duct Temperature

Thermostat

1 = High Duct Temp. Thermostat Kit

0 = None

Digit 24 - Plenum High Static Switch

1 = Plenum High Static Switch Kit

0 = None

Digits 25 — 45 - Future Use

0 = None

0 0 0 0 0

41 42 43 44 45

SCXG-SVX01B-EN 11

Installation

Receiving and Handling

Shipping Package

Commercial self-contained units ship

assembled with protective coverings

over the coil and discharge openings.

Figure I-PC-1 illustrates a typical shipping

package.

Ship-Separate Accessories

Field-installed sensors ship separately

inside the unit’s main control panel. Extra

filters, sheaves, and belts ship in the unit’s

fan motor section. Condenser plugs,

spring isolators, and isopads ship in the

unit’s bottom left side.

Receiving Checklist

Complete the following checklist

immediately after receiving unit

shipment to detect possible shipping

damage.

 Inspect individual cartons before

accepting. Check for rattles, bent carton

corners, or other visible indications of

shipping damage.

 If a unit appears damaged, inspect it

immediately before accepting the

shipment. Make specific notations

concerning the damage on the freight

bill. Do not refuse delivery.

 Inspect the unit for concealed damage

before it is stored and as soon as

possible after delivery. Report

concealed damage to the freight line

within the allotted time after delivery.

Check with the carrier for their allotted

time to submit a claim.

 Do not move damaged material from

the receiving location. It is the receiver’s

responsibility to provide reasonable

evidence that concealed damage did

not occur after delivery.

 Do not continue unpacking the

shipment if it appears damaged. Retain

all internal packing, cartons, and crate.

Take photos of damaged material if

possible.

 Notify the carrier’s terminal of the

damage immediately by phone and

mail. Request an immediate joint

inspection of the damage by the carrier

and consignee.

 Notify your Trane representative of

the damage and arrange for repair.

Have the carrier inspect the damage

before making any repairs to the unit.

pre-installation

considerations

Figure I-PC-1. Typical unit mounted on shipping skid.

12 SCXG-SVX01B-EN

pre-installation

considerations

Installation

Installation Preparation

Before installing the unit, perform

the following procedures to

ensure proper unit operation.

1. Verify the floor or foundation is level.

Shim or repair as necessary. To ensure

proper unit operation, install the unit

level (zero tolerance) in both horizontal

axis. Failure to level the unit properly

can result in condensate management

problems, such as standing water

inside the unit. Standing water and wet

surfaces inside units can result in

microbial growth (mold) in the drain

pan that may cause unpleasant odors

and serious health-related indoor air

quality problem.

2. Allow minimum recommended

clearances for maintenance and

routine service. See “Service Access”

section on page 13.

3. Position the unit and skid assembly in

its final location. If unit shipped split-

apart, follow the procedure in the

“Split-Apart Unit Assembly” section

on page 16 before completing this

step. Test lift the unit to determine exact

unit balance and stability before

hoisting it to the installation location.

See Figure I-PC-7 and I-PC-8 on page 15

for typical rigging procedures,

including cautions and proper uses of

such equipment as fork lifts, spreader

bars, and hooks.

4. Remove the skids from under the unit.

See the “Rigging and Handling”

section on page 14. Refer to the “Skid

Removal” section on page 18. If you

find internal damage, file a claim

immediately to the delivering carrier.

5. Remove the protective shipping covers

from the unit. Refer to the “Unit

Protective Covers” section on page 35.

Note: Unit height and connection locations

will change if external vibration isolators are

used. The unit may be raised an additional

5-7/8 inches with spring-type isolators.

Note: Unit height and connection locations

will change if the unit is constructed to be

split-a-part in the field. See unit submittal

drawings for connection locations.

6. Electrical supply power must meet

specific balance and voltage

requirements, as described in the

“Electrical Requirements” section on

page 33.

7. Water-cooled units only (model

SCWG): The installer must furnish and

install a condenser main and standby

water pump, cooling tower, pressure

gauges and all components for the

waterside piping. See the “Water

Piping” section on page 30 for general

waterside recommendations.

8. Air-cooled units only (model SCRG):

These units require field-installation of a

remote air-cooled condenser and

refrigerant piping. See the “Refrigerant

Piping” section on page 32 for general

piping recommendations.

SCXG-SVX01B-EN 13

Service Access





WARNING

Hazardous Voltage w/Capacitors!

Disconnect all electric power, including

remote disconnects before servicing.

Follow proper lockout/tagout proce-

dures to ensure the power cannot be

inadvertently energized. For variable

frequency drives or other energy storing

components provided by Trane or others,

refer to the appropriate manufacturer’s

literature for allowable waiting periods

for discharge of capacitors. Verify with an

appropriate voltmeter that all capacitors

have discharged. Failure to disconnect

power and discharge capacitors before

servicing could result in death or serious

injury.

Note: For additional information regard-

ing the safe discharge of capacitors, see

PROD-SVB06A-EN or PROD-SVB06A-FR.

See Figure I-PC-2 and Table I-PC-1 for

recommended service and code

clearances. Access to thermostat unit

controls is through a hinged access panel

door on the front, lower left of the unit’s

compressor section.

IntelliPak unit controls access is through

a panel on the middle right of the fan

section. The panel is secured with an

automatic latch and quick-acting fasten-

ers, which require a screwdriver to open.

Removable front unit panels provide

access to compressors, fan, motor, inlet

guide-vane actuator, and belts.

Removable left side panels give access to

drive side, fan bearing, inlet guide-vanes,

condensers, and waterside economizer

control valve. The compressor, con-

denser and fan motor access panels are

secured with quick-acting fasteners.

Access panels for evaporator coils,

expansion and water valves, and left fan

bearing are sheet metal screws. Access

to other components for service requires

removal of panels secured with sheet

metal screws. During operation, sight

glasses are viewable through portholes

on the upper right side panel of the fan

section.

Figure I-PC-2. Top view of self-contained unit showing recommended service and code clear-

ances

pre-installation

considerations

Installation

Table I-PC-1. Service and code clearance requirements

Side Distance Purpose

front 42 in. (20-38 tons) NEC code requirement

left 18 in. air-cooled units only

36 in. refrigeration & waterside component service

77 in. fan shaft removal

right 36 in. provides uniform airflow

inlet 18 in. provides uniform airflow

air inlet 18” minimum

See table

42” minimum

36”minimum

Control

Panel

Variable Frequency Drives are shipped

separately and field installed. See page 29

for VFD related dimensions and weights.

Top View

CCRC/CIRC 20, 29, 32

96” (2132 mm)

48” (1066 mm)

Control

Panel

96” (2132 mm)

48” (1066 mm)

14 SCXG-SVX01B-EN

pre-installation

considerations

Installation

Rigging and Unit Handling





WARNING

Improper Unit Lift!

Test lift unit approximately 24 inches to

verify proper center of gravity lift point.

To avoid dropping of unit, reposition

lifting point if unit is not level. Failure to

properly lift unit could result in death or

serious injury or possible equipment or

property-only damage.





WARNING

Lifting Equipment Capacity!

Ensure lifting equipment capacity

exceeds unit weight by an adequate

safety factor to prevent injury, death, or

unit damage.

Figure I-PC-5. Assembled unit gravity block location.

Table I-PC-2. Gravity Block Dimensions

Model A B C D

SCWG 36 14 38 12

SCRG 36 1 6 40 12

Fan Section Only

Compressor Section Only

Before lifting the unit or modular

component, determine the approximate

center of gravity for lifting safety. See

Figure I-PC-5 for assembled modular

units and Figure I -PC-6 for split-apart

units. The center of gravity may vary

slightly within the gravity block

depending on unit options.

Always test-lift the unit to determine the

exact unit balance and stability before

hoisting it to the installation location. See

Figures I-PC-7 and I-PC-8 for typical

rigging procedures and proper rigging

equipment usage.

Figure I-PC-6. Split-apart unit gravity block location.

SCXG-SVX01B-EN 15

pre-installation

considerations

Installation

Figure I-PC-8. Split-apart modular unit proper rigging.

Figure I-PC-7. Assembled modular unit proper rigging.

Unit Handling Procedure

NOTICE

Do not use hooks to lift unit or hook into

open channels to lift unit. This could

cause unit damage.

1. Position rigging sling under wood

shipping skid.

2. Use spreader bars to avoid unit

damage.

3. When using a forklift, exercise caution

to prevent unit damage.

4. Use the standard fork length to lift one

end and drag or pull unit while skidding

the opposite end.

5. The unit center of gravity will fall within

center of gravity block at various

locations depending on unit options.

6. Use hooks to lift fan section only. Do not

hook into open channels to lift unit.

7. See unit nameplate for unit weight.

8. Do not stack units.

16 SCXG-SVX01B-EN

Installation

pre-installation

considerations

Split-Apart Unit Assembly

1. Ensure the tagging information on the

fan section nameplate matches that on

the compressor nameplate.

2. Remove the connector brackets

holding the the sheet metal shipping

cover on compressor section. Retain

brackets and screws.

3. Remove shipping cover from the

compressor section and verify the ship-

with packge contains:

• suction and discharge line couplings

• insulation

• sheet metal screws

4. Lift fan section onto the compressor

section using the rigging method in

Figure I-PC-8 on page 13.

5. Remove skid from the fan section,

placing the fan section onto the

compressor section. Reference Figure I-

PC-9.

6. Install the connection brackets with the

sheet metal screws (referenced in step

2) on all sides of the unit. Reference

Detail “A” in Figure I-PC-9.

7. Remove the unit panels labeled RU and

RL in Figure I-PC-10 on page 17. To

remove panels, first remove the four

shipping screws located in the corner of

each panel. Next, turn the remaining 1/4

turn fasteners to the unlatch position.

The panel is supported by a “lip”

channel. So, lift the panel up and off the

unit to remove it. See Detail “A”in

Figure I-PC-9.

8. Connect the drain hose to the drainpan

outlet fitting and secure it with the drain

hose clamp provided.

9. Circulate nitrogen thoughout

refrigerant circuits.

10. Unbraze and remove the caps on the

discharge and suction lines in both the

compressor and fan sections.

11. Install and braze discharge and

suction line couplings.

12. Insulate discharge and suction lines

with the insulation provided.

13. Remove panel FLR and open the

bottom control panel door, FLL. Pull the

fan motor leads (coiled in the fan

section) through the knockout in the

bottom of the fan section to the control

panel. Ensure that the bushing is

installed in the hole to prevent the

wires from chafing. Refer to the unit

wiring diagrams to connect the fan

motor leads properly and ensure

correct phase sequencing.

IntelliPak Units(UCM) Only

14. Remove panels FML, FMM, and FMR.

15. Pull the circular plug connector (CPC)

from the compressor section through

the knockouts into the fan section.

Install the bushings (provided on the

wiring harnesses) in the knockouts.

16. Using the CPC wiring diagram,

connect the male CPC to the female

CPC in the top control panel.

17. If the unit has the mixed air

temperature option, route the capillary

tube on back of the filter rack.

Units with Thermostat Only

18. Remove panel FMR. See Note 1 on

Figure I-PC-10.

19. Pull frost protection wires from the

bottom control panel throughknockouts

in bottom of fan section. Route wires to

the appropriate frost protection

switches on the evaporator coil.

Reference the unit wiring diagrams to

connect frost protection wiring

connectors.

Air-Cooled Units Only:

20. Route the refrigerant circuit wires for

circuits 1 and 2 from the bottom control

panel through the knockouts to the

solenoid valves. The solenoid valves

are located in the liquid refrigerant

lines on the right-hand side of the unit.

Refer to the unit wiring diagrams to

make splice connections.

SCXG-SVX01B-EN 17

Installation

pre-installation

considerations

Figure I-PC-9 How to assemble the split apart modular unit

Figure I-PC-10 Modular unit panel description and internal connections

18 SCXG-SVX01B-EN

pre-installation

considerations

Installation

Skid Removal

The unit ships on skids to provide forklift

locations from the front or rear. The skid

allows easy maneuverability of the unit

during storage and transportation.

Remove the skids before placing the unit

in its permanent location.

Remove the skids using a forklift or jack.

Lift one end of the unit off of the skids.

See Figure I-PC-5 and I-PC-6 for unit

gravity block location. Slide the skids out

and lower the unit at the installation

location.

Note: External isolation is not necessary

since units are internally isolated. Consult a

vibration specialist before “double-

isolating” the unit.

External Unit Isolation

If your job requires external vibration

isolation, two options are available:

isopads or spring-type isolators. Isopads

should be placed under the unit at

locations indicated on the factory-

provided isolator sheet.

Set the spring-type isolators (Figure I-PC-

9) in position after the unit is removed

from skids before making electrical,

piping, or duct connections. All units

require a minimum of four isolators per

unit. But some may require six isolators,

depending upon unit options.

Note: Trane strongly recommends you

consult a vibration specialist before

double-isolating the unit. Double isolation

is not recommended.

If you decide to externally isolate the unit,

use spring-flex, type CP isolators. The

spring number is marked on the outer

housing. See Figure I-PC-9.

To install external isolators, complete the

following procedure.

1. Locate the isolators under unit base at

the locations indicated on the factory-

provided isolator placement sheet. Lift

one end of the unit at a time to position

isolators to the floor, using anchor bolts.

2. Level the unit by adjusting isolator

heights. Unit weight may cause the

upper housing to rest on the lower

housing of the spring isolators. The

isolator clearance shown in the side

Figure I-PC-9. Optional spring isolator dimensional data.

view of Figure I-PC-9, must be 1/4 - 1/2

inches. To increase the clearance, lift

the unit off the isolator and turn the

leveling bolt counterclockwise. Recheck

the unit level and the housing

clearances. Maximum allowable

difference between isolator heights is 1/4

inch. Shim as required under the

isolators.

Note: The compressors and fan assembly

are internally isolated on most units. Due to

this, the addition of external isolation

devices (spring mounting isolators) is at

the discretion of the building or HVAC

system designer.

Pre-Installation Checklist

Complete the following checklist before

beginning unit installation.

 Verify the unit size and tagging with the

unit nameplate.

 Make certain the floor or foundation is

level, solid, and sufficient to support the

unit and accessory weights. Level or

repair the floor before positioning the

unit if neccesary.

 Allow minimum recommended

clearances for routine maintenance and

service. Refer to unit submittals for

dimensions.

 Allow three fan diameters above the

unit for the discharge ductwork. Return

air enters the rear of the unit and

conditioned supply air discharges

through the top.

 Electrical connection knockouts are on

the top, left side of the unit.

 Allow adequate space for piping

access and panel removal. Condenser

water piping, refrigerant piping, and

condensate drain connections are on

the lower left end panel.

Note: Unit height and connection locations

will change if using vibration isolators. The

unit height may increase up to 5 7/8” with

spring type isolators.

 Electrical supply power must meet

specific balance and voltage

requirements as described in the

“Electrical Requirements” section.

 Water-cooled units only: The installer

is responsible for providing a condenser

main, standby water pump, cooling

tower, pressure gauges, strainers, and

all components for waterside piping.

See the “Water Piping” section for

general waterside recommendations.

 Air-cooled units only: The installer is

responsible for providing and installing

the remote air-cooled condenser and

refrigerant piping, including filter driers.

SCXG-SVX01B-EN 19

SCWG

SIRG

Dimensions &

Weights

SCWG/SIWG Dimensions, in.

left-side view

factory-piped units

front view

left-side view

direct condenser connections

top view

back view

right-side view

factory-piped units right-side view

direct-condenser connections

SCWG/SIWG weight, lbs.

unit tons base weight

20 2260

25 2730

30 2864

35 3000

Notes:

1. All unit weights include refrigerant, water, inlet guide

vanes and controllers, electric heat and valves.

2. Add 150 lbs. to total weight to obtain approximate

shipping weight.

3. Split-apart unit weights are approximately: 60% total

unit weight = compressor section, 40% total unit weight

= fan section.

20 SCXG-SVX01B-EN

SCRG /

SIRG

Dimensions &

Weights

SCRG/SIRG Dimensions, in.

SCRG/SIRG Weight, lbs.

unit tons base weight

20 2344

25 2479

32 2614

Notes:

1. All unit weights include refrigerant, water, inlet guide

vanes and controllers, electric heat and valves.

2. Add 150 lbs. to total weight to obtain approximate

shipping weight.

3. Split-apart unit weights are approximately: 60% total

unit weight = compressor section, 40% total unit weight

= fan section.

back view

top view

front view

left-side view

right-side view

SCXG-SVX01B-EN 21

Dimensions &

Weights

Detail Dimensions, in.

model A B C D E F

SCWG/SCRG 20 2 0 10 3/458 1/25 1/813 1/411 1/2

SCWG/SCRG 25 19 1/412 1/457 5/85 1/813 1/411 1/2

SCWG 30 - 35/SCRG 32 1 8 14 5/856 1/25 1/813 1/4

11 1/2

front view

shown with horizontal discharge option

top view

shown with vertical discharge option

SCRG/SIRG/SCWG/SIWG Detail “A”

Electrical Connections, in.

Detail “B” Discharge Options , in.

22 SCXG-SVX01B-EN

CCRC /

CIRC

Dimensions &

Weights

B

C

(LIQUID LINE CONNECTION REFRIG. CIRCUIT 1)

(HOT GAS CONNECTION REFRIG. CIRCUIT 1)

(LIQUID LINE CONNECTION REFRIG. CIRCUIT 2)

(HOT GAS CONNECTION REFRIG. CIRCUIT 2)

REFRIGERANT CIRCUIT 2

REFRIGERANT CIRCUIT 1

CCRC/CIRC Air-cooled condenser dimensions & weight, in-lbs.

shipping operating

model A A A B A C weight weight

CCRC/CIRC 20 70

1/888 88 2030 1906

CCRC/CIRC 29 70

1/888 88 2084 1960

CCRC/CIRC 32 70

1/888 88 2138 2014

CCRC/CIRC Refrigerant connections, in.

model E F G H J K L M N

CCRC/CIRC 20-32 66 7/814 3/818 1/224 3/429 5/81 1/85/81 1/8

CCRC/CIRC Electrical connections, in.

model A B C

CCRC/CIRC 20-32 4

1/210 1/217 1/2

CCRC/CIRC — Air-Cooled Condenser

SUPPLY VOLTAGE WIRE ENTRY HOLE

SIZED FOR 1” CONDUIT

115 VOLT WIRE ENTRY HOLE SIZED FOR

3/4” CONDUIT

24 VOLT WIRE ENTRY HOLE SIZED

FOR 3/4” CONDUIT

OPTIONAL LOW

AMBIENT DAMPER

REFRIGERANT

LINE

CONNECTIONS

FRONTAL VIEW

OPTIONAL LOW

AMBIENT DAMPER

(ONE DAMPER PER

CIRCUIT)

AA

AB

AC

SCXG-SVX01B-EN 23

Hot water coil dimensions & weight, in-lbs.

unit size A B C D E F G H J weight

20 - 35 tons 37 1/453 3/416 5/873 1/214 7/816 1/443 1/45 5/87 3/4460

Dimensions &

Weights

Hot Water Coil

24 SCXG-SVX01B-EN

Steam Coil

Dimensions &

Weights

Steam coil dimensions, in-lbs.

unit size A B C D E K L M N P Q R weight

20 - 35 tons 37 1/453 3/416 5/873 1/210 7/822 1/23 3/815 7/81419

3/84 3/8460

SCXG-SVX01B-EN 25

Electric Heat Coil

Electric heat coil dimensions & weight, in-lbs.

unit size A B C D weight

20 tons 70 1/44 7/811 1/219 460

25 tons 70 1/44 1/811 1/219 460

30 - 35 tons 70 1/42 7/811 1/219 460

Note: Coil box height is 8 in.

Flexible horizontal discharge plenum dimensions & weights, in-lbs.

20-35 tons A B C weight

low height 3 5 17 1/486 1/2262

standard height 3 5 25 1/486 1/2352

Flexible Horizontal Discharge

Plenum

Dimensions &

Weights

26 SCXG-SVX01B-EN

Waterside Economizer

Waterside economizer weight, in-lbs.

weight

unit size 2-row 4-row

20 - 35 tons 488 584

Dimensions &

Weights

SCXG-SVX01B-EN 27

Airside

Economizer

Dimensions &

Weights

Airside economizer dimensions & weight, in-lbs.

unit size A B C D E F (1) F (2) G (1) G (2) H (1) H (2) J K L M weight

SCWG/SIWG 20, 25 3 6 65 5/837 74 1/46 1/856 1/249 3/423 1/420 1/25 5/87 20 1/217 1/81 2 49 3/4273

SCRG/SIRG 20

SCWG/SIWG 30, 35 3 6 65 5/837 74 1/46 1/861 3/862 3/428 1/820 1/23 1/47 20 1/217 1/85 1/262 3/4273

SCRG/SIRG 25, 32

Airside Economizer

Detail “A”

Detail “B”

28 SCXG-SVX01B-EN

VFD

A

B

C

D

E

F

G

VFD dimensions, in.

voltage hp A B C D E F G

460 7.5 15.55 15.12 7.87 8.66 0.39 0.24 7.87

10

208 7.5 22.05 21.26 7.87 9.53 0.83 0.30 10.24

10

460 15

20

25

208 15 27.56 26.77 10.63 12.13 0.83 0.30 11.05

20

460 30

40

208 30 31.50 30.71 10.63 12.13 0.75 0.30 11.65

460 50

60

208 40 31.49 30.71 10.63 14.57 1.97 - 13.19

Dimensions &

Weights

Variable Frequency Drive

Option (VFD)





WARNING

Control and Line Voltage!

Control and line voltage wiring from the

VFD to the unit must be in accordance

with all local and National Electric Codes.

Do not touch circuit components until

main power has been turned off and

“charge” lamp is extinguished. The

capacitors are still charged and could

result in death or serious injury.





WARNING

Hazardous Voltage w/Capacitors!

Disconnect all electric power, including

remote disconnects before servicing.

Follow proper lockout/tagout proce-

dures to ensure the power cannot be

inadvertently energized. For variable

frequency drives or other energy storing

components provided by Trane or others,

refer to the appropriate manufacturer’s

literature for allowable waiting periods

for discharge of capacitors. Verify with an

appropriate voltmeter that all capacitors

have discharged. Failure to disconnect

power and discharge capacitors before

servicing could result in death or serious

injury.

Note: For additional information regard-

ing the safe discharge of capacitors, see

PROD-SVB06A-EN or PROD-SVB06A-FR.

NOTICE

Use Copper Conductors Only!

Unit terminals are not designed to

accept other types of conductors. Failure

to use copper conductors may result in

equipment damage.

The variable frequency drive (VFD) option

can only be used with IntelliPak units. The

VFD and VFD w/bypass is available from

5 to 25 hp and is a Trane TR1. All VFD’s are

pre-configured and run tested at the

factory prior to shipping. The VFD is wall

mounted.

There must be a minimum eight inch

clearance above and below the VFD. A

minimum two inch clearance is required

on each side.

Also, allow enough clearance for opening

the VFD cabinet door. This will ensure

sufficient air space for cooling.

Refer to the “Dimensions and Weights”

section beginning on page 19 for VFD

dimensions and weights.

Mounting Requirements

Proper location of the VFD is important to

achieve proper performance and normal

operating life. Installation must be in an

area where it will be protected from:

• Direct sunlight, rain or moisture.

• Corrosive gases or liquids.

• Vibration, airborne dust, or metallic

particles.

For effective cooling as well as proper

maintenance, install the VFD vertically to

the ground using four mounting screws.

SCXG-SVX01B-EN 29

VFD

Dimensions &

Weights

Variable Frequency Drive with Bypass

VFD with bypass dimensions, in.

voltage hp A B C D E F G H

460 7.5 30.40 28.03 16.14 23.35 24.85 0.75 8.59 10.63

10

208 7.5 41.28 38.89 16.14 24.00 25.5 0.75 10.95 12.99

10

15

20

460 15

20

25

208 25 50.81 48.35 21.36 31.61 33.41 0.90 12.36 14.41

H

G

E

D

F

B

A

C

Electrical Installation Procedure

Refer to the

National Electric Code,

section 310-16

for sizing wires 4B - 9B. All

other control wires should be twisted

shielded or twisted pair shielded, 20 - 14

AWG, with lead length not to exceed 164

feet. When using shielded wire, the shield

sheath must be connected at the VFD

only. The connection on units with VFD is

J13-S. The connection on unis with VFD/

bypass is ITBI-10.

30 SCXG-SVX01B-EN

Water Piping





WARNING

High Pressure Water!

Provide relief valves on system water

piping to prevent instantaneous release

of high pressure water. Failure to provide

relief valves could result in death or

serious injury or water pump damage or

unit failure.

Condenser Connections

Condenser water piping knockouts are in

the lower left end panel. If necessary,

remove insulation to gain access. All field

installed piping must conform to

applicable local, state, and federal codes.

To complete condenser water

connections follow the procedure below.

Note: Four condenser waterline drain plugs

ship in a bag in the unit’s left end. The

installer must field install these four plugs

using pipe thread sealer. An additional plug

is provided for units with a waterside

economizer.

1. Attach the water supply line to the inlet

connection, and the return line to the

outlet connection. Entering and leaving

water connections for all condensers

are factory manifolded and require only

single connections for entering and

leaving water. If the unit has a

waterside economizer and/or control

valves, the factory pipes between these

components.

2. If using a cooling tower, refer to Figure

I-MR-2 for a typical piping circuit from

the unit.

3. Ensure the water pressure to the unit

does not exceed 400 psig.

Note: To prevent water pump damage,

design system piping to provide relief

when using energy saving waterside

economizer valves.

Duct Connections





WARNING

Hazardous Voltage w/Capaci-

tors!

Disconnect all electric power, including

remote disconnects before servicing.

Follow proper lockout/tagout proce-

dures to ensure the power cannot be

inadvertently energized. For variable

frequency drives or other energy storing

components provided by Trane or others,

refer to the appropriate manufacturer’s

literature for allowable waiting periods

for discharge of capacitors. Verify with an

appropriate voltmeter that all capacitors

have discharged. Failure to disconnect

power and discharge capacitors before

servicing could result in death or serious

injury.

Note: For additional information regard-

ing the safe discharge of capacitors, see

PROD-SVB06A-EN or PROD-SVB06A-FR.

Return air enters the rear of the unit and

conditioned supply air discharges through

the top. Attach supply air ductwork

directly to the unit’s top panel, around the

fan discharge opening. A duct collar is not

provided.

Note: Units equipped with the flexible

horizontal discharge plenum option may

include a duct collar when holes are factory

cut. If discharge openings are field-cut, refer

to the “Plenum Installation” section.

Install all air ducts according to the

National Fire Protection Association

standards for the “Installation of Air

Conditioning and Ventilation Systems

other than Residence Type (NFPA 90A)

and Residence Type Warm Air Heating

and Air Conditioning Systems (NFPA

90B).

Make duct connections to the unit with a

flexible material such as heavy canvas. If

a fire hazard exists, Trane recommends

using Flexweave 1000, type FW30 or

equivalent canvas. Use three inches for

the return duct and three inches for the

discharge duct. Keep the material loose to

absorb fan vibration.

Note: The compressors and fan assembly are

internally isolated. Therefore, external isolation

devices (spring mounting isolators) are at the

discretion of a vibration specialist consulted

by the building or HVAC system designer.

Run the ductwork straight from the

opening for a minimum of three fan

diameters. See Figure I-MR-1. Extend

remaining ductwork as far as possible

without changing size or direction. Do not

make abrupt turns or transitions near the

unit due to increased noise and excessive

static losses. Use elbows with splitters or

turning vanes to minimize static losses.

Poorly constructed turning vanes may

cause airflow generated noise. Align the

fan outlet properly with the ductwork to

decrease noise levels in the duct and to

increase fan performance. To complete

trunk ductwork to the VAV terminal units,

refer to the VAV box manuals for specific

requirements. Check total external static

pressures against fan characteristics to

be sure the required airflow is available

throughout the ductwork.

To achieve maximum acoustical perfor-

mance, minimize the duct static pressure

setpoint.

Figure I-MR-1. Duct connection recommenda-

tions

3 Fan

Diameters

Discharge

Duct

3-inch

Flexible

Duct

Return

Air

Mechanical

Specifications

SCXG-SVX01B-EN 31

Mechanical

Specifications

Condensate Drain Connections

The condensate drain is internally

trapped. Condensate drain connections

are on the unit’s left side. Connect

condensate drain piping to the 1 1/4“ NPT

female fitting, using at least 7/

8

” OD

copper or 3/4“ OD iron pipe. Pitch the

condensate line downward a minimum

of 1/2” for each 10' of horizontal run, away

from the unit. Be sure to install the

condensate drain “P” trap drain plug.

Before starting the unit, fill the trap with

water to prevent negative pressure in the

fan section from impeding condensate

flow. To facilitate drain pipe cleaning,

install plugged tees in place of

90°elbows.

General Waterside Recommendations:

Cooling Towers

Cooling tower control affects the unit

cycle rates. Condenser water

temperature swings from 10-15°F may

cause excessive compressor, water

valve, and unit cycling. Be sure to set the

tower controls to minimize compressor/

unit cycling.

Waterside Piping Arrangements

Install a condenser water pump between

the cooling tower (either open or closed)

and the self-contained unit. Lay out the

remainder of the system’s condenser

piping in reverse returns. This helps

balance the system by equalizing the

length of supply and return pipes.

Multistory buildings may use a direct

return system with balancing valves at

each floor.

Install the supply riser and its return in

close proximity. Furnish both with

permanent thermometers to check the

waterside balance during start-up and

routine maintenance checks.

Also, include strainers at each pump inlet

and unit. Install drain valves at the riser’s

base to allow drainage points for system

flushing during start-up and routine

maintenance. For condenser draining

and header removal, include a shutoff/

balancing valve on the entering and

leaving waterside pipes, drain tees, and

unions of each unit. Also, install a shutoff

valve on the unit entering water pipe for

condenser draining.

Note: Unit does not have floor drains.

Water Temperature Requirements

Do not allow the entering water

temperature to go below 54°F (12.2°C) on

units with constant water flow (basic

piping). This will cause the compressors

to shut down and the mechanical cooling

function will lockout. However, the

economizer (if enabled) will continue to

function. The compressor s will reset

when the entering water temperature

reaches 58°F (15°C).

Units with variable water flow

(intremediate piping) have a modulating

condensing pressure control valve that

allows compressor operation down to

entering water temperatures of 35°F

(2°C).

For more information on constant and

variable water flow, see the Sequence of

Operation section of this manual.

Note: Units with a waterside economizer

can be set from the human interface panel

for variable or constant water flow.

Table I-MR-1. Water Connection Sizes.

Unit Size Direct Condenser Factory Piped

SCWG 20-35 1-1/2 NPT 2-1/2 NPT

Figure I-MR-3. Direct condenser connections.

Figure I-MR-2. Condenser water piping components for cooling tower system

32 SCXG-SVX01B-EN

Refrigerant Piping (Air-Cooled

Units Only)

See the “Startup” section of this manual

for instructions on refrigerant evacuation,

charging, and superheat measurement.

Leak-test the entire refrigeration system

after all piping is complete.

Leak Test (Remote Air-cooled Units Only)

Units ship with a holding charge of dry

nitrogen. Before installing the unit

refrigerant piping, momentarily depress

either the suction or discharge line access

valve to verify the holding charge has not

been lost. If no nitrogen escapes the

access valve, leak-test the entire

refrigerant system to determine the leak

source. Use a halogen leak detector, a

halide torch, or soap bubbles to leak test.

After finding a leak, remove the test

pressure and repair the leak. Retest the

unit to ensure all leaks are repaired.

Brazing Procedures

Proper brazing techniques are essential

when installing refrigerant piping. The

following factors should be kept in mind

when forming sweat connections:





WARNING

Hazard of Explosion and Deadly

Gases

Never solder, braze or weld on refriger-

ant lines or any unit components that are

above atmospheric pressure or where

refrigerant may be present. Always

remove refrigerant by following the

guidelines established by the EPA Federal

Clean Air Act or other state or local

codes as appropriate. After refrigerant

removal, use dry nitrogen to bring

system back to atmospheric pressure

before opening system for repairs.

Mixtures of refrigerants and air under

pressure may become combustible in

the presence of an ignition source

leading to an explosion. Excessive heat

from soldering, brazing or welding with

refrigerant vapors present can form

highly toxic gases and extremely

corrosive acids. Failure to follow all

proper safe refrigerant handling practices

could result in death or serious injury.

1. When heating copper in the presence

of air, copper oxide forms. To prevent

copper oxide from forming inside the

tubing during brazing, sweep an inert

gas, such as dry nitrogen, through the

tubing. A nitrogen flow of 6 to 10 cubic

feet per hour is sufficient to displace the

air in the tubing and prevent oxidation

of the interior surfaces. Use a pressure

regulating valve or flow meter to

control the flow.

2. Ensure that the tubing surfaces

requiring brazing are clean, and that the

tube ends are carefully reamed to

remove any burrs.

3. Make sure the inner and outer tubes of

the joint are symmetrical and have a

close clearance, providing an easy ‘slip’

fit. If the joint is too loose, the

connection’s tensile strength is

significantly reduced. Ensure the

overlap distance is equal to the inner

tube diameter.

4. Wrap each refrigerant line component

with a wet cloth to keep it cool during

brazing. Excessive heat can damage

the internal components.

5. If using flux, apply it sparingly to the

joint. Excess flux will contaminate the

refrigerant system.

6. Apply heat evenly over the length and

circumference of the joint.

7. Begin brazing when the joint is hot

enough to melt the brazing rod. The hot

copper tubing, not the flame, should

melt the rod.

8. Continue to apply heat evenly around

the joint circumference until the brazing

material is drawn into the joint by

capillary action, making a mechanically

sound and gas-tight connection.

9. Visually inspect the connection after

brazing to locate any pinholes or

crevices in the joint. Use a mirror if joint

locations are difficult to see.

10. Reference Tables M-MP-6 and M-MP-

7 for the correct amount of refrigerant

required for charging the unit.

Mechanical

Specifications

SCXG-SVX01B-EN 33

Specific unit wiring diagrams are

provided on the inside of the control

panel door. Use these diagrams for

connections or trouble analysis.

Supply Power Wiring





WARNING

Hazardous Voltage w/Capacitors!

Disconnect all electric power, including

remote disconnects before servicing.

Follow proper lockout/tagout proce-

dures to ensure the power cannot be

inadvertently energized. For variable

frequency drives or other energy storing

components provided by Trane or others,

refer to the appropriate manufacturer’s

literature for allowable waiting periods

for discharge of capacitors. Verify with an

appropriate voltmeter that all capacitors

have discharged. Failure to disconnect

power and discharge capacitors before

servicing could result in death or serious

injury.

Note: For additional information regard-

ing the safe discharge of capacitors, see

PROD-SVB06A-EN or PROD-SVB06A-FR.

It is the installer’s responsibility to

provide power supply wiring to the unit

terminal block or the non-fused

disconnect switch option. Wiring should

conform to NEC and all applicable code

requirements.

Bring supply wiring through the knockout

in the lower left side of the unit control

panel. Connect the three phase wires to

the power terminal block or the non-

fused disconnect switch in the control box

terminals. Refer to specific wiring

diagrams and fuse information in the

unit’s control panel.

NOTICE

Use Copper Conductors Only!

Unit terminals are not designed to

accept other type conductors. Failure to

use copper conductors may result in

equipment damage.

NOTICE

Equipment Damage!

Correct phase sequence is critical. If

phase sequence of the incoming line

voltage is not correct, it may result in

motor damage.

Voltage Range

Voltages must be within +- 10% the

nameplate voltage. Ensure the unit

voltage is balanced by measuring at the

compressor terminals. Voltage imbalance

on three phase systems can cause motor

overheating and premature failure.

Maximum allowable imbalance is 2.0%.

Voltage Imbalance

Read the voltage at the compressor

terminals to determine if it is balanced.

Voltage imbalance on three phase

systems can cause motor overheating

and premature failure. The maximum

allowable imbalance is 2.0%. Voltage

imbalance is defined as 100 times the

sum of the deviation of the three voltages

from the average (without regard to sign)

divided by the average voltage. For

example, if the three measured voltages

are 221, 230, and 227, the average voltage

would be:

(221 + 230 + 227) = 226 volts

3

The percentage of voltage imbalance is

then:

100 * (226-221) = 2.2%

226

Electrical

Requirements





WARNING

Live Electrical Components!

During installation, testing, servicing and

troubleshooting of this product, it may be

necessary to work with live electrical

components. Have a qualified licensed

electrician or other individual who has

been properly trained in handling live

electrical components perform these

tasks. Failure to follow all electrical

safety precautions when exposed to live

electrical components could result in

death or serious injury.

Control Power

NOTICE

Component Failures!

Unit transformers IT1, IT3, 1T4, and IT5

are sized to provide power to the unit

only. Do not use these transformers to

supply power to field equipment. Field

connections to these transformers may

create immediate or premature compo-

nent failures.

In this example, 2.2% imbalance is not

acceptable. Whenever a voltage

imbalance of more than 2.0% exists,

check the voltage at the unit disconnect

switch. If the imbalance at the unit

disconnect switch does not exceed 2.0%,

faulty unit wiring is causing the

imbalance. Conduct a thorough

inspection of the unit electrical wiring

connections to locate the fault, and make

any repairs necessary.

Access the connection terminal block

through the control panel on the unit’s

upper left side. All wiring should conform

to NEC and applicable local code require-

ments.

Be sure all wiring connections are secure.

Reference the unit specific diagrams

inside the control panel.

Unit Wiring Diagrams

34 SCXG-SVX01B-EN

Selection Procedures

RLA = rated load amps

Compressor LRA = locked rotor amps

Fan motor LRA = locked rotor amps,

N.E.C. table 430 - 150

FLA = full load amps, N.E.C.

Table 430 - 150

Voltage utilization range is ±10%

Determination of minimum circuit

ampacity (MCA).

MCA = 1.25 x largest motor amps/VFD

amps (FLA or RLA) + the sum of the

remaining motor amps.

Determination of maximum fuse size

(MFS) and maximum circuit breaker size

(MCB).

MFS and MCB = 2.25 x largest motor

amps (FLA or RLA) + the sum of the

remaining motor amps.

For units with the dual power option,

there are two electrical circuits that need

calculations using the formulas above:

circuit #1 - fans

circuit #2 - compressors

If the rating value determined does not

equal a standard current rating of over

current protective device, use the next

lower standard rating for the marked

maximum rating.

Table ED-1. Number of Compressors per Unit

SCWG/SIWG 20 25 30 3 5

SCRG/SIRG 20 25 32

10 HP 2 2 1 -

15 HP - - 1 2

Table ED-2. SCWG/SIWG Compressor Motor Data

200V 460V 575V

HP RLA LRA RLA LRA RLA LRA

10 33.1 269 14.4 117 11.5 94

15 46.9 409 20.4 178 16.4 143

Table ED-3. SCRG/SIRG Compressor Motor Data

200V 460V 575V

HP RLA LRA RLA LRA RLA LRA

10 38.4 269 16.7 117 13.4 94

15 55.0 409 24.1 178 19.1 143

Table ED-4. Fan without VFD

200V 460V 575V

HP FLA LRA FLA LRA FLA LRA

5 16.1 105 6.7 46 5.4 37

7.5 25.0 152 10.8 66 8.2 54

10 32.9 193 14.2 84 11.4 66

15 44.8 290 20.3 126 16.2 102

20 61.0 373 25.0 162 20.0 132

25 74.0 469 31.0 204 24.2 162

Table ED-5. Fan with VFD

200V 460V

HP FLA LRA FLA LRA

7.5 13.8 152 10.6 66

10 32.2 193 14.2 84

15 48.3 290 21.0 126

20 61.9 373 27.6 162

25 78.2 469 34.0 204

Note: Values are at the maximum VFD input rating and not the reduced motor values.

Table ED-6. Electric Heat - Single Stage

SCWG/SIWG SCRG/SIRG Heat 200V 460V

Size Size Kw Amps Amps

20 20 16 44.8 19.6

25 25 20 55.6 24.2

30 - 24 66.8 29.0

- 32 26 72.4 31.6

35 - 28 78 34.0

Note: Electric heat amperage should not be considered when determining minimum circuit ampacity. The current of the

unit in the heating mode will not exceed the current of the unit in the cooling mode.

Table ED-7. CCRC/CIRC Condenser Electrical Data

Unit Size Rated MFS/

Tons Voltage # Fans FLA (ea.) LRA (ea.) MCA MCB

20, 29, 32 200 4 4.1 20.7 17.4 20

230 4 4.1 20.7 17.4 20

460 4 1.8 9.0 7.7 15

575 4 1.4 7.2 6.0 15

Note: All motors for CCRC/CIRC units are rated at 1 hp (.7457 kW).

Electrical

Requirements

SCXG-SVX01B-EN 35

pre-startup

requirements

Installation

Pre-Startup Procedures





WARNING

Hazardous Voltage w/Capacitors!

Disconnect all electric power, including

remote disconnects before servicing.

Follow proper lockout/tagout proce-

dures to ensure the power cannot be

inadvertently energized. For variable

frequency drives or other energy storing

components provided by Trane or others,

refer to the appropriate manufacturer’s

literature for allowable waiting periods

for discharge of capacitors. Verify with an

appropriate voltmeter that all capacitors

have discharged. Failure to disconnect

power and discharge capacitors before

servicing could result in death or serious

injury.

Note: For additional information regard-

ing the safe discharge of capacitors, see

PROD-SVB06A-EN or PROD-SVB06A-FR.

Before starting up units perform the

following procedures to ensure proper

unit operation.

Figure I-PR-2. Fan isolator locations.

Figure I-PR-1. Supply fan horizontal isolation

shipping bracket.

Unit Protective Covers

Remove the shipping protection

coverings from the human interface

panel (HI) at the control panel, the filter

box (or air inlet opening), the discharge

air opening, and optional variable

frequency drive (VFD).

Compressor Isolators

Loosen compressor isolator mounting

bolts and remove shipping bracket from

beneath the compressor feet. Retighten

isolator mounting bolts. Torque to 18 ft.

lbs. (+ 2 ft. Lbs.)

Supply Fan Isolators

Remove the shipping channels and

mounting bolts from beneath the fan. See

Figure I-PR-1. Open both fan

compartment access doors to access the

channels. There are four mounting points

for 20-38 ton units and six mounting

points for 40-80 ton units. See Fig I-PR-2.

Note: For 20-38 ton units, do not remove the

fan assembly shipping blocks and tie down

bolts if the fan speed is 750 rpm or less.

While keeping the fan mounting frame

level, turn the fan isolator height adjusting

bolts until the fan housing P-gasket

compresses 1/4” against the roof transi-

tion piece. See Figure I-PR-1.

36 SCXG-SVX01B-EN

pre-startup

requirements

Plenum

Before installing the plenum attach the

insulation strip that ships with the plenum.

See Figure I-PR-3 for proper insulation

location. Align the plenum front with the

control panel side of the unit. Using the

strips and screws provided, secure the

plenum to the unit.

Treat field-cut holes to prevent fiberglass

from entering the airstream.

Note: Plenum insulation must be applied

properly to prevent air bypass around the

plenum. See Figure I-PR-3.

Figure I-PR-3. Correct plenum insulation placement

Plenum Bottom View

Dashed line indicates correct insulation placement.

Installation

SCXG-SVX01B-EN 37

pre-startup

requirements

Airside Economizer

Installation

Note: Airside economizer option available on

20-80 tons only.

Unit Handling

1. Hoist the damper cabinet to the

installation location with straps

positioned under the skid as shown in

Figure I-PR-4. Use spreader bars to

prevent unit damage during lifting.

2. With the damper cabinet at its final

location (near the unit), remove the

screws securing it to the skid from the

side flanges. Retain these screws for

later use.

Unit Preparation

3. The support legs are secured to the

skid, and the hanging bracket is secured

with wire ties to an inside flange near

the cabinet’s base. Remove the C-

channel collar and install it on the unit, if

not already installed.

4. Remove the roll of 1/8” thick gasket

from the damper cabinet’s W-supports,

and apply it to the C-channel collar

mounted on the rear of the unit. This

gasket will provide a seal between the

damper cabinet and the unit.

5. Attach the legs (with screws provided)

to the leg brackets located on the

damper’s base.

6. Attach a field-provided clevis of

suitable strength ( > 1/2” ), to each of the

corner lifting brackets through the

7/8” diameter holes.

7. Attach to the clevises a means of lifting

the damper cabinet from its skid.

Unit Installation

8. Slowly raise the damper cabinet from

its skid.

9. Attach the hanging bracket across the

front of the damper cabinet. Position it

with its short flange pointing to four

Figure I-PR-4. Proper lifting of the airside economizer

o’clock, and secure it with screws

provided. See Figure I-PR-5.

10. Lift the damper cabinet and position it

such that the hanging bracket is

positioned over the unit’s C-channel

collar.

11. Lower the damper cabinet until the

holes in its side flanges are aligned with

the holes in the C-channel collar. Install

screws removed in step 3 through the

damper cabinet’s side flanges and into

the C-channel’s corresponding holes.

12. Attach ductwork to the top and back

dampers according to local codes.

Field Wiring Connections

13. Open the damper cabinet’s door and

connect the factory-provided plug from

the actuator to the factory-provided

plug in the unit’s filter section.

Figure I-PR-5. Proper installation of the airside economizer option

14. Cabinets with TRAQ dampers only:

Unroll the two rolls of pneumatic tubing

located inside the damper cabinet.

Route these tubes through the cabinet’s

front upper panel (0.25 dia. holes

provided). Connect them to the two

pneumatic tubes protruding from the

customer electrical connection panel on

the unit. Be sure to connect like tubes to

each other (black to black, white stripe

to white stripe).

15. Cabinets with TRAQ dampers only:

Locate the “bullet” sensor and rolled up

wiring in the unit’s filter section. Route it

into the damper cabinet and insert the

sensor into the sensor mounting clip

attached to underside of one of the Traq

dampers.

Installation

Airside

Economizer

38 SCXG-SVX01B-EN

pre-startup

requirements

Static Pressure Transducer

Installation (VAV units only)

Supply air static pressure controls the

inlet guide vane and inverter options. A

static pressure head assembly ships

separate in the control panel for field

installation in the supply air duct work.

The installer is responsible for providing

pneumatic tubing.

Transducer Location

Place the head assembly in an area of the

ductwork that will provide an average

and evenly distributed airflow pattern.

Use the following guidelines to determine

an appropriate installation location.

1. Locate the static head assembly about

2/3 to 3/4 of the way down the longest

duct run, in an area approximately 10

duct diameters downstream and 2 duct

diameters upstream of any major

interferences, turns, or changes in duct

diameter.

2. When installing pneumatic tubing

between the head assembly and

transducer in the control panel, do not

exceed 250 feet for 1/4” OD tubing or

500 feet for 3/8” OD tubing.

Installing the Transducer

Complete the following procedure to

properly install the inlet guide vane static

pressure transducer.

1. Mount the pressure sensing head

assembly in the duct so that the sensing

tip is in the middle of the duct so that it

will provide a proper pressure

measurement. See Figure I-PR-6.

2. Connect the pneumatic tubing from the

sensing head to the push-on tubing

connection in the control panel. Use a

plastic static pickup tubing. Do not

exceed 250 feet for 1/4“ OD tubing or

500 feet for 3/8” OD tubing.

The transducer inside the control panel

picks up low side or reference pressure.

Note: If plastic tubing pulls away from a

connection, trim it back before replacing it

on the fitting. Stretched tubing may leak

and cause faulty control.

Installation

Figure I-PR-6. Static pressure sensor installation

SCXG-SVX01B-EN 39

pre-startup

requirements

Installation

Figure I-PR-7. Installing the waterside economizer.

Waterside Economizer

Installation Procedure

1. Loosen and pull all end devices that go

throught the bushing on the filter rack

(upper right corner of rack).

2. Remove the filter rack from the back of

the unit by removing the 1/4” hex head

screws from the top and bottom of the

filter rack assembly. The filter rack

assembly will hang on the unit when

the screws are removed. Remove the

filter rack by lifting it up off the unit.

3. Remove the economizer from the

crate and position it behind the unit with

the headers on the left side, when

facing the back of the unit. Remove the

plastic envelope that is taped to the

economizer box assembly. This

envelope contains the gasket that must

be installed onto the vertical side

flanges of the box.

4. Install the pressure sensitive gasket to

the unit side of the vertical flange on

the economizer box.

5. Hang the economizer on the unit as

shown in Figure I-PR-7. Lift the

economizer by using the holes

provided in the top panel of the

economizer.

6. Align economizer holes with the holes

in the unit channel. Install screws in the

top (6x) and bottom (6x) of the

economizer.

7. Remove the unit’s rear middle panel

and unbraze the two copper pipes in

the 2 5/8” water pipe. Do not remove

the pipe outlet blockoff panel.

8. Remove the economizer tubing

assemblies from the shipping box.

Check ship-separate parts against

those shown in Figures I-PR-8, I-PR-9, I-

PR-10, and I-PR-11. Face the front of the

unit to see which side the water pipe

exits to determine if the unit has either

right or left-hand piping.

9. Assemble tubing as shown in Figure I-

PR-8 or I-PR-11. Tack all tubes in place

before brazing to ensure proper fit-up.

For right-hand piped units, install the

ball valve actuator assembly and

actuator as shown in Figure I-PR-10.

Refer to the unit wiring diagram for

wiring connection points.

10. Install the pipe insulation on all pipe

line to prevent sweating

11. Install the rear panels.

12. Re-install the filter rack on the back of

the economizer coil box and affix with

screws provided.

40 SCXG-SVX01B-EN

pre-startup

requirements

Installation

Figure I-PR-9. Waterside economizer with left-hand factory piping tubing assembly

Item Part Description

A Assembly #1

B Assembly #2

C Assembly #3

D Assembly #4

E Tube; 2 5/8” x 16 7/8”

F Tube; 2 5/8” x 22 5/8

Figure I-PR-8. Detail view of ship-separate

tubing assemblies for waterside econo-

mizer left-hand piping

Waterside Economizer with left-hand

factory piping components

Waterside Economizer Ship-Separate Parts List

Factory Item Part # Qty. Description

Piping

Left-Hand 4001 2 Tube; 2 5/8” x 9”

X17110026250 5 Elbow; 2 5/8” x 2 5/8”

4003 1 Tube; 2 5/8” x 26 1/8”

4740 1 Tube; 2 5/8” x 33 1/2”

4009 1 *Tube; 2 5/8” x 14 7/8”

X21040098390 10 ft. *Gasket

X21080406110 1 *Insulation; 2 5/8” Rubatex

X16120203570 1 Plug; 1 1/2” Brass

X17150027060 1 Bushing; 2 1/2” ftg. x 1 1/2”

X17170031210 1 Tee; 2 5/8” x 2 1/8” x 2 5/8”

4738 1 *Tube; 2 5/8” x 19 3/4”

4007 1 Tube; 2 5/8” x 14 1/2”

X45000032020 1 roll Tape, 1.5’ wide

4006 1 Tube; 2 5/8” x 19 15/16”

SCXG-SVX01B-EN 41

pre-startup

requirements

Installation

Figure I-PR-10. Waterside economizer with right-hand factory piping tubing assembly.

Item Part Description

A Assembly #1

B Assembly #2

C Assembly #3

D Assembly #4

E Tube; 2 5/8” x 11 3/4”

F Tube; 2 5/8” x 20 1/4”

G Actuator Assembly

Figure I-PR-11. Detail view of ship-separate tubing assemblies for waterside economizer right-hand factory piping.

Waterside Economizer with right-hand

factory piping components

Waterside Economizer Ship-Separate Parts List

Factory Item Part # Qty. Description

Piping

Right-Hand 4001 1 Tube; 2 5/8” x 9”

4607 1 Tube; 2 5/8” x 17”

X17110026250 5 Elbow; 2 5/8” x 2 5/8”

4605 2 Tube; 2 5/8” x 9 1/2”

X15330177010 1 Water Valve

4008 1 *Tube; 2 5/8” x 20 1/4”

X17170031210 1 Tee; 2 5/8” x 2 1/8” x 2 5/8”

X16120203570 1 Brass Plug, 1 1/2”

X17150027060 1 Bushing; 2 1/8” ftg. x 1 1/2”

4007 1 Tube; 2 5/8” x 14 1/2”

4031 1 Tube; 2 5/8” x 62

4603 1 *Tube; 2 5/8” x 11 3/4”

4006 1 Tube; 2 5/8” x 19 1/4”

X13610256010 1 *Actuator with wires

X19110028040 2 *90 Degree Conduit Fitting

X19110028040 3 ft. *1/2” Conduit

X210804060110 14 ft. *Rubatex Insulation, 2 5/8”

X45000032020 1 roll Tape, 1.5’ wide

X21040098390 10 ft. *Gasket

42 SCXG-SVX01B-EN

pre-startup

requirements

Installation

Hydronic Coil Installation

These instructions are for steam and hot

water coil installation. The hydronic coil

assembly has a full coil, piping, a modu-

lating temperature control valve, and a

disc temperature limit device located in

the unit near the fan on the motor frame.

Hydronic coils are available with either

right or left-hand pipe connections. Piping

connections are identical to the unit

piping. For example, if you have right-

hand unit piping, the hydronic coil will

have right-hand connections. The

hydronic coil assembly has temperature

controls to keep the unit’s internal cabinet

temperature below 105 F to prevent

motor and bearing damage.

Installation Procedure





WARNING

Unit Structural Integrity!

Unit panels provide structural integrity.

Do not remove more than two non-

adjacent panels at one time as this could

cause the plenum frame to collapse.

Failure to follow these recommendations

could result in death, serious injury or

equipment damage.

1. Remove filter rack from the back of the

unit. Remove the 1/4-inch hex head

screws from the top and bottom of the

filter rack assembly. The filter rack

assembly will hang on the unit when

the screws are removed. The filter rack

can now be removed by lifting up on

the filter rack.

2. Remove the hydronic coil from the

crate and position it behind the unit with

the open side facing the unit evaporator

coil inlet. Also, remove the plastic

envelope that is taped to the coil box

assembly. This envelope contains the

mounting screws needed to attach the

coil box to the unit and the gasket

required on the vertical side flanges of

the box.

3. Install the pressure sensitive gasket to

the unit side of the vertical flange on the

coil box in two places.

4. Using 2” x 1/2” standard thread

eyebolts, thread into the coil lift plates

to raise the coil up to the height

necessary to attach it to the unit. The top

panel has a “J” hook on it to allow

hanging, similar to the filter rack. Align

the holes so that the coil hangs on the

unit. If the unit has the dirty filter option,

connect the static pressure tube to the

unit before bolting the coil in place.

Locate the static pressure tubing on the

unit evaporator coil and route through

the knockout in the top corner of the

coil box.

5. Align the hydronic coil with the holes in

the unit channel or waterside

economizer option. Move the coil box

up against the unit and install using six

mounting screws in the top and six in

the bottom of the coil box.

6. Remove the valve and pipe cover on

the coil box. Connect the wires that are

coiled in the coil box, referring to the

wiring diagram installed on the unit

control panel door. Route wires into the

unit through knockouts in the top of the

box.

7. Reinstall the filter rack on the back of

the heating coil rack. If the unit has the

waterside economizer option, the filter

rack will require additional support legs.

SCXG-SVX01B-EN 43

pre-startup

requirements

Installation

Electric Heat Installation

The electric heat option consists of a

single stage heater and is used in

IntelliPak units or units with a field-

installed thermostat. The electric heater

ships separate for field installation and

wiring. Available heater kW per unit size

is listed in Table I-PR-2. Electric heat can

be installed on units with a vertical

discharge. However, it cannot be installed

on units with plenums. See Figure I-PR-12

and Table I-PR-3 for electric heat dimen-

sional data.

Table I-PR-2. Available Electric Heat kW

Unit Size Heater kW

20 Tons 1 6

25 Tons 2 0

30 Tons 2 4

32 Tons 2 6

35 Tons 2 8

Installation Procedure

1. Remove the fan discharge shipping

covers, if they have not already been

removed.

2. Install the open-cell gasket around the

discharge opening on the heater.

3. Position the electric heater so that the

unit fan discharge openings line up with

the electric heater openings. For a

Figure I-PR-12. Electric heater dimensions.

Table I-PR-3. Electric Heat Dimensions - English - (inches)

Unit Size B1 B2 Z

20 Tons 10 3/415 5/827 3/4

25 Tons 12 1/415 5/826 3/4

30, 32, 35 Tons 14 3/415 5/823 3/4

Figure I-PR-12. Vertical discharge electric heat

installation.

vertical discharge unit, position the

electric heater as shown in Figure I-PR-

12.

4. Use the hole pattern in the electric heat

as a template for marking and drilling

3/16” diameter holes in the unit.

5. Bolt the electric heaters to the unit

using 1/4” sheetmetal screws.

Note: It is very important that electric heaters

are selected based on unit voltage and

tonnage because discharge opening sizes vary

by unit tonnage.

Electric Heat Coil Wiring Procedure

NOTICE

Use Copper Conductors Only!

Unit terminals are not designed to

accept other type conductors. Failure to

use copper conductors may result in

equipment damage.





WARNING

Hazardous Voltage w/Capacitors!

Disconnect all electric power, including

remote disconnects before servicing.

Follow proper lockout/tagout proce-

dures to ensure the power cannot be

inadvertently energized. For variable

frequency drives or other energy storing

components provided by Trane or others,

refer to the appropriate manufacturer’s

literature for allowable waiting periods

for discharge of capacitors. Verify with an

appropriate voltmeter that all capacitors

have discharged. Failure to disconnect

power and discharge capacitors before

servicing could result in death or serious

injury.

Note: For additional information regard-

ing the safe discharge of capacitors, see

PROD-SVB06A-EN or PROD-SVB06A-FR.

1. Before wiring the electric heater,

remove the unit wiring diagram from

the unit control panel and refer to the

connection points.

44 SCXG-SVX01B-EN

Figure I-PR-10. BAYSENS110

Dual setpoint, manual/automatic changeover

sensor with system function lights, acces-

sory model number digit 6 = F

pre-startup

requirements

Figure I-PR-7. BAYSENS077

zone temperature sensor only

Standard with All IntelliPak

Units

Zone Sensor Options for IntelliPak Control Units

Zone sensor options are available and be ordered with the unit or after the unit ships.

Following is a full description of zone sensors and their functions. Installation

instructions are on page 34. Programming instructions for the programmable zone

sensor are on page 36. Refer to Table O-GI-2 on page 61 for the zone sensor

temperature vs. resistance coefficient curve.

BAYSENS077* Description

This zone sensor module ships with all units, and can be used with BAYSENS019,

BAYSENS020, or BAYSENS021 remote sensors. When this sensor is wired to one of

these remote zone sensors, wiring must be 18 AWG shielded twisted pair (Belden 8760

or equivalent). Refer to the specific zone sensor for wiring details. It provides the

following features and system control functions:

• Remote temperature sensing in the zone

• Morning warmup sensor

• Zone sensor for ICS™ systems

• Zone temperature averaging

When used as a remote sensor for standard zone sensor, the thermistor sensor must

be disabled.

(Possible Schematic Designation(s): 5U23, 5U26, 5U30, and 5RT5.)

CV Unit Zone Sensor Options

Figure I-PR-8. BAYSENS108

Dual setpoint, manual/automatic

changeover sensor, accessory model

number digit 6 = E

Installation

BAYSENS110-Specific Feature: Function status indicator lights:

• SYSTEM ON glows continuously during normal operation, or blinks if

system is in test mode.

• COOL glows continuously during cooling cycles, or blinks to indicate a

cooling system failure.

• HEAT glows continuously during heating cycles, or blinks to indicate a

heating system failure.

• SERVICE blinks or glows to indicate a problem. These signals vary

depending on the particular equipment being used.

BAYSENS108 & BAYSENS110 Description

These zone sensor modules are for use with cooling/heating constant volume units.

They have four system switch settings (heat, cool, auto, and off) and two fan settings

(on and auto). The zone sensor provides either manual or automatic chaneover control

with dual setpoint capability.

BAYSENS108 and BAYSENS110 features and system control functions include:

• System control switch to select heating mode (HEAT), cooling mode (COOL),

automatic selection of heating or cooling as required (AUTO), or to turn the

system off (OFF).

• Fan control switch to select automatic fan operation while actively heating

or cooling (AUTO), or continuous fan operation (ON).

• Dual temperature setpoint levers for setting desired temperature. The blue

lever controls cooling, and the red lever controls heating.

• Thermometer to indicate temperature in the zone. This indicator is factory

calibrated.

(Possible Schematic Designation: 5U29)

(Possible Schematic Designation: 5U29)

SCXG-SVX01B-EN 45

pre-startup

requirements

Figure I-PR-12. BAYSENS073

Zone temperature sensor w/timed override ,

accessory model number digit 6 = B

Figure I-PR-11. BAYSENS074

Zone temperature sensor w/timed override

and local setpoint adjustment,

accessory model number digit 6 = C

Integrated Comfort™ Systems Sensors for CV and VAV

Applications

These zone sensor options are for use with cooling/heating Integrated Comfort System

(ICS) systems.

BAYSENS074 Description

This electronic analog sensor features single setpoint capability and timed override

with override cancellation.

BAYSENS074 features and system control functions include:

• Remote temperature sensing in the zone

• A timed override button to move an ICS or a building management system from its

“unoccupied” to “occupied” mode.

• Thumbwheel for local setpoint adjustment

• A cancel button to cancel the “unoccupied override” command.

(Possible Schematic Designation: 5U23)

BAYSENS073 Description

This electronic analog sensor features single setpoint capability and timed override

with override cancellation. It is used with a Trane Integrated Comfort system.

BAYSENS073 features and system control functions include:

• Remote temperature sensing in the zone

• A timed override button to move an ICS or a building management system from its

“unoccupied” to “occupied” mode.

• Cancel button to cancel the “unoccupied override” mode.

(Possible Schematic Designation: 5U23)

CV and VAV Unit Zone Sensor

Options

Installation

Figure I-PR-9. BAYSENS021

Single setpoint sensor with system

function lights, accessory model number

digit 6 = H

BAYSENS021 Description

This zone sensor module is for use with VAV units without night setback. It allows the

user to control system operation and monitor unit operating status from a remote

location. The sensor has a system switch, a S/A temperature setpoint indicator, a local

sensor, and four LED’s.

BAYSENS021 features and system control functions include:

• Temperature sensing in the zone

• System control switch with mode setting for "AUTO" and "OFF"

• Supply air single temperature setpoint

• Function status indicator lights:

“SYS ON” glows continuously during normal operation, or blinks if system is in

test mode.

“COOL” glows continuously during cooling cycles, or blinks to indicate a

cooling system failure.

“HEAT” glows continuously during heating cycles, or blinks to indicate a

heating system failure.

“SERVICE” blinks or glows to indicate a problem. These signals vary

depending on the particular equipment being used.

(Possible Schematic Designation: 5U25)

VAV Unit Zone Sensor Option

46 SCXG-SVX01B-EN

literature for allowable waiting periods

for discharge of capacitors. Verify with an

appropriate voltmeter that all capacitors

have discharged. Failure to disconnect

power and discharge capacitors before

servicing could result in death or serious

injury.

Note: For additional information regard-

ing the safe discharge of capacitors, see

PROD-SVB06A-EN or PROD-SVB06A-FR.

NOTICE

Use Copper Conductors Only!

Unit terminals are not designed to

accept other types of conductors. Failure

to use copper conductors may result in

equipment damage.

Remove the zone sensor cover from

subbase, and mount subbase on the wall

or on a 2 x 4 junction box. Route wires

through the wire access hole in the

subbase. See Figure I-PR-14. Seal the hole

in the wall behind the subbase.

Note: Guidelines for wire sizes and lengths

are shown in Table I-PR-1. The total resis-

tance of these low voltage wires must not

exceed 2.5 ohms per conductor. Any resis-

tance greater than 2.5 ohms may cause the

control to malfunction due to excessive

voltage drop.

Note: Do not run low-voltage control wiring in

same conduit with high-voltage power wiring.

Wiring

1. Run wires between the unit control

panel and the zone sensor subbase. To

determine the number of wires

required, refer to the unit wiring

diagrams.

2. Connect the wiring to the appropriate

terminals at the unit control panel and

at the zone sensor subbase. In general,

zone sensor connections to the unit use

the convention of connecting zone

sensor terminals to like numbered unit

terminals (1 to 1, 2 to 2, etc.). The

connection detail is shown on the unit

wiring diagrams, which are located in

pre-startup

requirements

Standard zone sensors, BAYSENS077,

ships with all units

Zone Sensor Installation

All sensor options ship in the main control

panel and are field-installed.

Programmable option installation

procedures.

Mounting Location

Mount the sensor on the wall in an area

with good air circulation at an average

temperature. Avoid mounting space

temperature sensor is areas subject to

the following conditions:

• Drafts or “dead” spots behind doors or

in corners

• Hot or cold air from ducts

• Radiant heat from the sun or appliances

• Concealed pipes and chimneys

• Unheated or non-cooled surfaces

behind the sensor, such as outside walls

• Airflows from adjacent zones or other

units

To mount the sensors, remove the dust

cover and mount the base on a flat

surface or 2" x 4" junction box. Sensors

ship with mounting screws.

Mounting the Subbase





WARNING

Hazardous Voltage w/Capacitors!

Disconnect all electric power, including

remote disconnects before servicing.

Follow proper lockout/tagout proce-

dures to ensure the power cannot be

inadvertently energized. For variable

frequency drives or other energy storing

components provided by Trane or others,

refer to the appropriate manufacturer’s

Installation

the unit control panel.

3. Replace the zone sensor cover back on

the subbase and snap securely into

place.

Standard Remote Sensor (BAYSENS077)

When using the remote sensor,

BAYSENS077, mount it in the space that

is to be controlled. Wire according to the

interconnecting wiring diagrams on the

unit.

Table I-PR-1. Zone sensor maximum lengths

and wire size

Distance from Recommended

Unit to Controller Wiring Size

0-150 feet 22 gauge

151--240 feet 20 gauge

241-385 feet 18 gauge

386- 610 feet 16 gauge

611-970 feet 14 gauge

SCXG-SVX01B-EN 47

RIGHT BACK

1-3/32 [27,43 mm]

3/32 [2,00 mm]

1-3/8 [35,00 mm]

19/32 [15,00 mm]

15/64 [6,00 mm]

3-5/32 [80,00 mm]

1-1/32 [26,16 mm]

5/32 [3,81 mm] 4X

Figure I-PR-22. Zone sensor mounting hole locations for: BAYSENS077, BAYSENS073, BAYSENS074,

BAYSENS108, and BAYSENS110.

pre-startup

requirements

Installation

Zone sensor mounting hole locations for: BAYSENS021.

48 SCXG-SVX01B-EN

Junc

Mounting to Junction Box

Mounting Directly to the Wall

Figure I-PR-23. Typical zone sensor installation for vertically-oriented sensors

Installation

pre-startup

requirements

SCXG-SVX01B-EN 49

pre-startup

requirements

Constant Volume Zone Sensor

BAYSENS019 Description

This seven day programmable sensor

with night setback has four periods for

occupied\unoccupied programming per

day. If power is interrupted, the program

retains in permanent memory. If power is

off longer than two hours, only the clock

and day may have to be reset.

The six programming keys on the front of

the zone sensor allow selection of system

modes (heat, cool, auto, and off), two fan

modes (on and auto). The zone sensor

has dual temperature selection with

programmable start time capability.

The occupied cooling setpoint range is 40

to 80°F. The warmup setpoint range is 50

to 90°F with a 2° deadband. The

unoccupied cooling setpoint range is 45 to

98°F. The heating setpoint range is 43 to

96°F.

Two liquid crystal displays (LCD) display

zone temperature, setpoints, week day,

time, and operational mode symbols.

The DIP switches on the subbase enable

or disable applicable functions; i.e.

morning warmup, economizer minimum

CFM override during unoccupied status,

Fahrenheit or Centigrade, supply air

tempering, remote zone temperature

sensor, 12/24 hour time display, smart

fan, and computed recovery.

During an occupied period, an auxiliary

relay rated for 1.25 amps @ 30 volts AC

with one set of single pole double throw

contacts activates.

Figure I-PR-16. BAYSENS019, program-

mable night setback sensor, accessory

model number digit 6 = G

Variable Air Volume Zone Sensor

BAYSENS020B Description

This seven day programmable sensor

with night setback has four periods for

occupied\unoccupied programming per

day. Either one or all four periods can be

programmed. If power is interrupted, the

program retains in permanent memory. If

power is off longer than twohours, only

the clock and day may have to be reset.

The zone sensor keypad allows you to

select occupied/unoccupied periods with

two temperature inputs (cooling supply

air temperature and heating warmup

temperature) per occupied period. The

occupied cooling setpoint ranges be-

tween 40 and 80°F. The warmup setpoint

ranges between 50 and 90°F with a 2°

deadband. The unoccupied cooling

setpoint ranges between 45 and 98°F.

The heating setpoint ranges between 43

and 96°F.

The liquid crystal display (LCD) displays

zone temperature, setpoints, week day,

time, and operational mode symbols.

The DIP switches on the subbase enable

or disable applicable functions; i.e.

morning warmup, economizer minimum

position override during unoccupied

status, heat installed, remote zone

temperature sensor, 12/24 hour time

display, and daytime warmup. During an

occupied period, an auxiliary relay rated

for 1.25 amps @ 30 volts AC with one set

of single pole double throw contacts

activates.

Figure I-PR-17. BAYSENS020, program-

mable night-setback sensor,

accessory model number digit 6 = J

Programmable Zone Sensors

Programmable zone sensors provide

programming and zone temperature

sensing for the self-contained unit. It

allows the user to monitor room

temperatures and program settings in

the space, without having to access the

unit control panel.

Reference programming instructions for

these zone sensors beginning on page 44.

Installation

50 SCXG-SVX01B-EN

pre-startup

requirements

Programmable Zone Sensor

Installation

Mounting Location

Mount the sensor on the wall in an area

with good air circulation at an average

temperature. Choose a location that is

easily accessible, and on a wall where the

subbase can be mounted about 5 feet

(1.5 meters) above the floor.

Avoid mounting space temperature

sensor in areas subject to the following

conditions:

• Drafts or “dead” spots behind doors or

in corners

• Hot or cold air from ducts

• Radiant heat from the sun or appliances

• Concealed pipes and chimneys

• Unheated or non-cooled surfaces

behind the sensor, such as outside walls

• Airflows from adjacent zones or other

units

Installation Procedure

1. Remove the zone sensor module from

the subbase. Carefully hold the zone

sensor module with one hand and

firmly grasp the subbase with the other.

See Figure I-PR-20. To remove the zone

sensor module from the subbase,

gently pull away and upward.

Note: The zone sensor module is an

electronic sensitive device. Do not touch

printed circuit board, electronic compo-

nents, or connector pins. Handle plastic

housing only to prevent damage to

electronic components.

2. After disassembly, protect the internal

surfaces from contact with objects or

substances that could cause damage.

3. Remove the terminal block from

subbase and set aside for wiring.

Discard the tape.

4. Mount the zone sensor module using

the mounting hardware included in the

shipping package. The mounting

hardware is contained in single plastic

bag and includes:

• Plastic wall anchors (3 x)

• Mounting screws (3 x)

The zone sensor module can mount

directly to a wall or to a junction box

mounted to a wall. To mount to a

junction box, you must have the

mounting plate and adapter kit,

BAYMTPL003. Installation instructions

are enclosed with the mounting plate.

5. To mount the zone sensor module

directly to a wall:

Figure I-PR-21. Securing the subbase

Figure I-PR-20. Removing the zone sensor

module from the subbase

Installation

Figure I-PR-18. BAYSENS019 dimensions

Figure I-PR-19. BAYSENS020 dimensions

(140 mm)

(95 mm)

(140mm)

(95mm)

a. Hold the subbase in position and mark

the three mounting hole locations on

the wall.

b. Drill three

3

/

16

” (4.8 mm)

holes. Gently

tap the plastic wall anchors into the

holes until the anchor tops are flush

with the wall.

6. Pull the zone sensor module wires

through the subbase as shown in Figure

I-PR-21.

7. Loosely secure subbase to the wall

with the mounting screws. Do not

tighten the subbase screws yet.

8. Level the subbase by sight, then firmly

tighten the three subbase mounting

screws.

Note: Do not overtighten the subbase

screws. Overtightening may cause the

screws to crack the subbase.

9. Before wiring the subbase, identify the

wires from the unit’s low voltage

terminal strip. Each screw terminal is

labeled.

10. Remove TB from subbase and

discard the tape.

11. Strip the wires

1

/

4

” and

connect the

wires from the unit’s low voltage

terminal strip to the zone sensor

module subbase. Reference connection

details on the unit wiring diagrams,

located on the unit.

12. Firmly tighten each screw terminal.

13. Fit the wires as close to the subbase

as possible.

SCXG-SVX01B-EN 51

pre-startup

requirements

Time Clock Option

The time clock option has a

programmable timer that is factory wired

to the unoccupied input to provide on/off

control. The time clock will not allow the

unit to pass through the night setback/

morning warmup mode, except on units

with optional night heat/morning warm

up, or programmable night setback. See

Figure I-PR-22.

The timeclock, a “Digi 20” by Grasslin, is

inside the control panel, but accessible

with the control panel door closed. This

same type timer is also used for pro-

grammable night setback/morning warm

up. Programming instructions for the

“Digi 20” timer are in the “Program-

ming” section.

Time Clock Installation

1. Ensure operating temperature is

between 4°F and 131°F.

2. Locate the time clock at least 5 feet

away from any large electrical contact

or machinery to avoid possible

electrical interference problems.

3. Provide a separate independent circuit

for the time clock power supply.

4. Since all electronic instruments are

sensitive to voltage spikes, pay close

attention tot he following:

a. If possible, supply power to the

electronic time clock from a phase

different than the one supplying power

to the load.

b. Provide a suitable Varistor or RC

network across the INDUCTIVE

LOADS supply terminals to reduce

voltage spikes.

c. Place a diode across the DC

OPERATED INDUCTOR terminals to

eliminate back EMF.

d. HIGHLY INDUCTIVE LOADS, especially

fluorescent lights, may require a relay

in which case step a. and c. apply.

The timeclock can be surface or flush

mounted. Lift off the front cover and

loosen the two screws on opposite

corners. Pull off the base’s plug with a left

to right rolling motion.

Time Clock Installation Checklist

1. Ensure operating temperature is 4°F to

131°F.

2. Locate the time clock at least 5 feet

away from any large electrical contact

or machinery to avoid possible

electrical interference problems.

3. Provide a separate independent circuit

for the time clock

power supply.

4. Since all electronic instruments are

sensitive to voltage spikes, pay close

attention to the following:

a. If possible, supply power to the

electronic time clock from a phase

different than the one supplying power

to the load

b. Provide a suitable Varistor or RC

network across the INDUCTIVE LOADS

supply terminals to reduce voltage

spikes.

c. Place a diode across the DC OPERATED

INDUCTOR terminals to eliminate back

EMF.

d. HIGHLY INDUCTIVE LOADS, especially

fluorescent lights, may require a relay

in which case (A) and (C) apply.

The Digi 20A timeclock unit can be

surface or flush mounted. Lift off the

front cover and loosen the two screws on

opposite corners. Pull off the base’s plug

with a left to right rolling motion.

Surface Mounting Inside Panel

Place screws through the base’s preset

holes and screw to back of panel or wall.

Wire according to the instructions in the

following section. Depending upon the

specific installation, you may find it more

convenient to complete wiring before

attaching the base.

Place the terminal cover over the

terminal block by aligning the two screws

with the corner holes in the base. Push

the timer firmly onto the plug in the base.

Tighten the two screws. A base for DIN

rail mounting is optional.

Wiring theTimeclock

1. Wire 24, 120, or 220 VAC to input

terminals. Make sure to apply correct

voltage. Using incorrect voltage will

void the warranty.

2. Connect wire to the screw terminals

according to the unit wiring diagrams.

Use 12 to 22 AWG wire.

Figure I-PR-22. Grasslin time clock option

Installation

52 SCXG-SVX01B-EN

pre-startup

requirements

Figure I-PR-23. Human interface (HI) panel keypad

Remote Human Interface Panel

Installation

Human Interface (HI) Panel

The HI enables the user to communicate

necessary unit operating parameters and

receive operating status information

from within the occupied space.

The HI displays top level information in

the LCD window, unless the operator

initiates other displays, for the various

unit functions. It also displays menu

readouts in a clear language 2 line, 40

character format. The 16-key keypad

allows the operator to scroll through the

various menus to set or modify the

operating parameters. See Figure I-PR-

23 to reference the HI keypad.

Remote Human Interface Panel

The remote human interface (RHI) panel

is identical to the unit mounted HI with the

exception of the “unit select” key. This

key allows the operator to switch from

one unit to the next to program or view

status information regarding a particular

unit.

The RHI functions the same as the unit

mounted HI with two exceptions. The first

is the “test start” function. The operator

can view the service parameters, but can

only initiate the service test function at

the unit. The RHI door has a locking screw

to deter access by unauthorized person-

nel. Additionally, the RHI can control up to

four different units.

Location Recommendations

The HI microprocessor module is

mounted inside a molded plastic

enclosure for surface mounting. It is not

weatherproof. Therefore, it is only

applicable for indoor use.

Locate the RHI panel in an area that will

ensure the communication link between

the panel and the unit(s) does not exceed

5,000 feet maximum or pass between

buildings. See Table I-PR-2.

The run length of the low voltage AC

power wiring to the remote HI must not

exceed three (3) ohms/conductor. Refer

to Table I-PR-3.

Ambient Temperature and Humidity

Limits

Ambient Operating Conditions

• Temperature: 32 to 120°F

• Relative humidity: 10 to 90%, non-

condensing

Ambient Storage Conditions

• Temperatures: -50 to 200°F

• Relative humidity: 5 to 95%, non-

condensing

Table I-PR-2. Maximum communication link

wiring length

max. wire max. capacitance

length between conductors

1,000 ft up to 60 pf/ft

2,000 ft up to 50 pf/ft

3,000 ft up to 40 pf/ft

4,000 ft up to 30 pf/ft

5,000 ft up to 25 pf/ft

Note: pf/ft = picofarads/foot

Table I-PR-3. Wiring recommendations for the

remote HI panel

distance recommended

to remote HI wire size

0-460 feet 18 gauge

461-732 feet 16 gauge

733-1000 feet 14 gauge

Installation

SCXG-SVX01B-EN 53

pre-startup

requirements

Mounting the Remote Human

Interface (RHI) Panel

The installer must provide all mounting

hardware such as; hand tools, electrical

boxes, conduit, screws, etc. Refer to

Figure I-PR-24 for the mounting hole and

knockout locations.

Procedure

Refer to Figure I-PR-24 and follow the

procedure below for mounting the

remote HI panel on a 4” by 4” electrical

junction box. Place the microprocessor in

a clean dry location during the enclosure

mounting procedures to prevent

damage.

1. Mount an electrical junction box in the

wall so that the front edge of the box

will be flush with the finished wall

surface.

2. Prior to mounting the panel, the

microprocessor module must be

carefully removed from the enclosure.

To remove the module:

a. Lay the remote panel face up on a flat

surface and remove the locking screw

from the right hand bottom end of the

panel.

b. Remove the recessed hinge screw

from the left hand bottom end of the

panel.

c. Unlatch the door of the enclosure as if

to open it, and slide the left hand side of

the door upward away from the hinge.

Lay it aside.

d. With the key pad visible, remove the

two (2) screws located on the right hand

side of the key pad.

e. Carefully slide the key pad plate

upward from the bottom, releasing the

extruded hinge pin from its socket at

the top.

f. Set the microprocessor aside until

mounting is complete.

3. Remove the junction box knockout in

the back of the enclosure.

Note: The top of the enclosure is marked

“TOP.”

4. With the enclosure in the correct

position; align the mounting holes

around the knockout in the enclosure

with the screw holes in the electrical

handy box and secure with the

appropriate screws.

5. Replace the microprocessor within the

enclosure as follows:

a. Verify that the terminal block jumpers

are connected properly.

b. Slide the extruded hinge pin at the top

left of the key pad plate into the hole

located at the top left hand side of the

enclosure.

c. Slide the bottom of the plate into place,

aligning the two (2) clearance holes

with the screw holes on the right. Install

the screws but do not tighten.

Note: If the two screws are not installed as

called out in the previous step, hold against

the key pad plate while installing the door

in the next step, to prevent it from falling

out.

d. Slide the extruded hinge pin at the top

left of the door into the hole located

under the bottom left side of the display.

e. Install and tighten the hinge screw

located at the bottom left side of the

enclosure.

Wall Mounting the RHI Panel

1. Prior to mounting the panel, the

microprocessor module must be

removed from the enclosure. Complete

step 2 in the previous discussion,

“Mounting on a 4 in. x 4 in. Electrical

Box,” before proceeding.

2. With the microprocessor removed,

refer to Figure I-PR-24 for the location of

the mounting holes to be used for wall

mounting.

3. Place the enclosure against the

mounting surface and mark the

mounting holes.

Note: The top of the enclosure is marked

with “TOP.”

4. With the enclosure in the correct

position, remove the enclosure and drill

the necessary holes in the surface for

the appropriate fasteners, (plastic

anchors, molly bolts, screws, etc.)

5. Remove the necessary knockouts for

the wire or conduit entry before

mounting the panel.

6. Place the enclosure back onto the

surface and secure it with the

appropriate screws.

7. Follow step 5 in the previous section,

“Mounting on a 4” by 4” Electrical

Box,” to replace the microprocessor

within the enclosure.

Installation

54 SCXG-SVX01B-EN

pre-startup

requirements

Figure I-PR-24. Remote HI mounting holes and knockout locations

Installation

SCXG-SVX01B-EN 55

Wiring the Remote Human

Interface

The remote human interface requires 24

VAC + 4 volts power source and a

shielded twisted pair communication link

between the remote panel and the

interprocessor communication bridge

(ICPB) module at the self-contained unit.

Field wiring for both the low voltage

power and the shielded twisted pair must

meet the following requirements:

Note: To prevent control malfunctions, do

not run low voltage wiring (30 volts or less)

in conduit with higher voltage circuits.





WARNING

Hazardous Voltage w/Capacitors!

Disconnect all electric power, including

remote disconnects before servicing.

Follow proper lockout/tagout proce-

dures to ensure the power cannot be

inadvertently energized. For variable

frequency drives or other energy storing

components provided by Trane or others,

refer to the appropriate manufacturer’s

literature for allowable waiting periods

for discharge of capacitors. Verify with an

appropriate voltmeter that all capacitors

have discharged. Failure to disconnect

power and discharge capacitors before

servicing could result in death or serious

injury.

Note: For additional information regard-

ing the safe discharge of capacitors, see

PROD-SVB06A-EN or PROD-SVB06A-FR.

1. All wiring must be in accordance with

NEC and local codes.

2. Reference Table I-PR-3 for

recommended wiring distance and size.

3. Communication link wiring must be 18

AWG shielded twisted pair (Belden

8760, or equivalent).

4. Communication link must not exceed

5,000 feet maximum for each link. See

Table I-PR-2.

5. Do not run communication link

between buildings.

Low Voltage (AC) Field Wiring

Connections

To access the wire entry locations, open

the RHI panel door and remove the two

screws on the right-hand side of the key

pad. Swing the keypad open, exposing

both the wire entries and the back of the

HI module. Refer to Figure I-PR-24 and

connect one end of the three conductor

24 volt wires to the remote panel

terminal strip (+), (-), and (ground).

Communication Link (Shielded Twisted

Pair) Wiring

Trim the outer covering of the shielded

cable back approximately 1 inch. See

Figure I-PR-25. Do not cut the bare shield

wire off. Strip approximately 1/2-inch of

insulation from each insulated wire to

connect them to the terminal strip at the

remote panel.

Connect the white lead to the positive (+)

terminal, the black lead to the negative (-)

terminal, and the bare shield wire to the

terminal at the remote human interface

panel.

Close the key pad plate. Install and

tighten the two screws removed earlier.

Close the outer door and install the

recessed locking screw at the bottom

right hand side of the enclosure to

prevent accidental starting of the unit by

unauthorized personnel while completing

the wiring at the self-contained unit.

At the Self-Contained Unit

Connect the opposite end of the three

conductor 24-volt wire to the appropriate

terminal strip as follows:

Note: Although the 24 volt power is not

polarity sensitive, do not connect either the +

(plus) or - (minus) terminals from the remote

panel to ground at the self-contained unit.

Connect the wire connected to the

positive (+) terminal at the remote panel.

Connect the wire connected to the

negative (-) terminal at the remote panel.

Connect the ground wire from the remote

panel to the unit control panel casing.

Interprocessor Communication Bridge

Module Wiring

Refer to Figure I-PR-25 and trim the outer

covering of the shielded cable back

approximately one inch. Cut the bare

shield wire off even with the outer

covering. Strip approximately 1/2-inch of

insulation from each insulated wire in

order to connect them to the terminal

strip at the unit. Wrap tape around any

exposed foil shield and/or base shield

wire.

Note: The communication link is polarity

sensitive.

Refer to the unit wiring diagram and

connect the white lead to the positive (+)

terminal and the black lead to the

negative (-) terminal. (These terminals

are numbered. Reference to color is for

clarification to maintain polarity).

Note: To maintain polarity, do not connect

the base shield wire to ground at the self-

contained unit.

Figure I-PR-25. Dressing shielded twisted wire

pre-startup

requirements

Installation

56 SCXG-SVX01B-EN

pre-startup

requirements

Installation

Connecting to Tracer Summit





WARNING

Hazardous Voltage w/Capaci-

tors!

Disconnect all electric power, including

remote disconnects before servicing.

Follow proper lockout/tagout proce-

dures to ensure the power cannot be

inadvertently energized. For variable

frequency drives or other energy storing

components provided by Trane or others,

refer to the appropriate manufacturer’s

literature for allowable waiting periods

for discharge of capacitors. Verify with an

appropriate voltmeter that all capacitors

have discharged. Failure to disconnect

power and discharge capacitors before

servicing could result in death or serious

injury.

Note: For additional information regard-

ing the safe discharge of capacitors, see

PROD-SVB06A-EN or PROD-SVB06A-FR.

IntelliPak commercial self-contained

(CSC) units operate with Trane building

automation software, Tracer Summit

version 10.0.4 or later or any OS2

operating system.

Note: Tape the non-insulated end of the

shield on shielded wire at the unit. Any

connection between the shield and ground

will cause a malfunction. If daisy-chained in

the unit, splice and tape the shields to

prevent contact with ground.

Communication Wiring

Note: Communication link wiring is a

shielded, twisted pair of wire and must

comply with applicable electrical codes.

An optional communication link provides

a serial communication interface (SCI)

between Tracer Summit and each

commercial self-contained (CSC) unit in

the system. The CSC system can have a

maximum of 12 CSC units per connection

link to Tracer Summit. Use a single 18

AWG shielded, twisted pair wire with

stranded, thinned copper conductors to

establish each communication link

between Tracer Summit and each unit.

Pre-Startup Checklist

Complete this checklist after installing the

unit to verify all recommended

installation procedures are complete

before unit start-up. This does not replace

the detailed instructions in the

appropriate sections of this manual.

Always read the entire section carefully

to become familiar with the procedures.

Receiving

Inspect unit and components for

shipping damage. File damage claims

immediately with the delivering carrier.

Check unit for missing material. Look

for ship-with drives, isolators, filters,

and sensors that are packaged

separately and placed inside the main

control panel, fan section, or

compressor section. See the “Receiving

and Handling” section.

Check nameplate unit data so that it

matches the sales order requirements.

Unit Location

Remove crating from the unit. Do not

remove the shipping skid until the unit is

set in its final position.

Ensure the unit location is adequate for

unit dimensions, ductwork, piping, and

electrical connections.

Ensure access and maintenance

clearances around the unit are

adequate. Allow space at the end of the

unit for shaft removal and servicing.

See the “Service Access” section.

Unit Mounting

Place unit in its final location.

Remove shipping skid bolts and skid.

If using isolators, properly mount unit

according to the isolator placement

sheet.

Remove shipping brackets on the

compressors and supply fan.

Remove the unit protective shipping

covers.

Component Overview

Verify the fan and motor shafts are

parallel.

Verify the fan and motor sheaves are

aligned.

Check the belt tension for proper

adjustment.

Ensure the fan rotates freely.

Tighten locking screws, bearing set

screws and sheaves.

Ensure bearing locking collars do not

wobble when rotated.

Ductwork

If using return ductwork to the unit,

secure it with three inches of flexible

duct connector.

Extend discharge duct upward without

change in size or direction for at least

three fan diameters.

Use a 3” flexible duct connection on

discharge ductwork.

Ensure trunk ductwork to VAV boxes is

complete and secure to prevent leaks.

Verify that all ductwork conforms to

NFPA 90A or 90B and all applicable

local codes

Water-Cooled Unit Piping

Verify the condensate drain piping is

complete for the unit drain pan. Install

and tighten the condensate “P” trap

drain plug.

Install water piping drain plugs,

economizer header, and condenser

vent plugs.

Make return and supply water

connections to the unit and/or waterside

economizer piping package with

recommended valves and piping

components. Refer to the “Water

Piping” section.

Install unions to allow waterside

maintenance.

Install cooling tower and standby

pumps.

Treat water to prevent algae, slime,

and corrosion.

Prevent refrigerant piping from rubbing

against other objects.

Air-Cooled Units Only

Connect refrigerant lines.

Install liquid line filter driers.

Units with Hydronic Heat

Verify the entering water temperature

sensor is installed upstream of the

hydronic coil.

Units with Electric Heat

Verify the supply air temperature

sensor is downstream of the electric

heat coil.

SCXG-SVX01B-EN 57

programmingInstallation

Figure I-P-1. BAYSENS019 keypad and display configuration

BAYSENS019 Keypad and Display

Explanation

1. Up and Down Buttons

• Increases or decreased programmed

temperature settings in program menu.

• Shifts to temporary manual override in

normal run mode.

•Increases or decreases temperature

while in temporary override menu.

2. Time Adjust Button

Used to set the correct time of day. Used

to set programmed time for temperature

variations.

3. Program Button

Toggles between the display control

screen and the display program screen.

4. Erase Button

• Erases time and temperature settings

throughout each of the programmed

periods.

• Exits temporary manual override.

5. Day Button

Toggles through the seven days of the

week.

6. Hold Temp Button

Shifts controller to temporary manual

override, and begins temperature

override.

7. Fan Button

Toggles the fan controller between on

and auto mode.

8. Mode Button

Toggles the controller through its 4

modes: off, heat, cool, and auto; if HP

version, also emer (emergency).

9.

• Indicates day of the week

• Indicates begin time in program menu

Indicates time setting in temporary

override mode.

Programmable Zone Sensor

Options

BAYSENS019

58 SCXG-SVX01B-EN

programmingInstallation

Figure I-P-2. BAYSENS020 keypad and display configuration

BAYSENS020

BAYSENS020 Keypad and Display

Explanation

1. Up and Down Buttons

• Increases or decreased programmed

temperature settings in program menu.

• Shifts to temporary manual override in

normal run mode.

•Increases or decreases temperature

while in temporary override menu.

• Pressed together, toggles between

unoccupied/occupied setting.

2. Time Adjust Button

Used to set the correct time of day. Used

to set programmed time for temperature

variations.

3. Program Button

Toggles between the display control

screen and the display program screen.

4. Erase Button

• Erases time and temperature settings

throughout each of the programmed

periods.

• Exits temporary manual override.

5. Day Button

Toggles through the seven days of the

week.

6. Hold Temp Button

Shifts controller to temporary manual

override, and begins temperature

override.

7. Mode Button

• Toggles the controller between the two

modes, off and auto.

• Advances to next setpoint in program

menu.

8. During Programming Indicates:

• Heat supply air

• Cool supply air

• Warmup temperature

SCXG-SVX01B-EN 59

Program Button

Depressing the program button will

toggle the display from normal run mode

to the program menu. See Figure I-P-3.

Before toggling to the program menu,

use the mode button to select the type

setpoints to review or program (heat,

cool or auto). For example, if you select

cool mode before toggling to the program

menu, then only the cool setpoints are

reviewed or programmed. If you select

heat mode, then only the heat setpoints

are reviewed or programmed. In auto

mode, both heat and cool setpoints are

reviewed and programmed.

• While in program menu, each time you

press and release the program button,

the ZSM toggles through the four

periods that divide each day. Those four

periods are: Morn(ing), Day, Eve(ning),

and Night.

• To exit the program menu, depress the

program button for two seconds.

Program Menu

BAYSENS020 Only

Note: After toggling to the program screen,

the week is divided into seven days with

each day divided into four periods.

Setpoint programming depends on the

setting status, occupied or unoccupied,

and whether or not heat is installed,

modulated heat, morning warmup, or

daytime warmup options are enabled.

In the occupied period, the cool supply air

temperature is always set. If heat

installed and modulated heat options are

on, the supply air heat is also set during

occupied periods. The warmup tempera-

ture is also set in occupied periods, if heat

programmingInstallation

Initial Power-Up

Before applying power to your ZSM, and

before performing setup and operation

procedures, verify that all wiring is

correct. See Figures I-P-9 on page 52 and

I-P-10 on page 53 for a complete zone

sensor icon display description.

For BAYSENS020 only: at initial power-

up, the ZSM controls to default tempera-

tures of 68°F (19°C) for warmup, and

55°F (13°C) supply air, until the ZSM is

programmed or the arrow keys are

pressed. If the arrow keys and mode are

moved, the ZSM starts controlling to

these new settings.

Time and Day Settings

On power-up your ZSM will be in normal

run mode and will begin operating using

setpoints. The display will show the

wrong day and time and will need to be

set.

To set the time, there is a single rubber

button on the keypad “minus” and

“plus” mark time.

Depressing the positive side will advance

the time. Depressing the negative side

will decrease the time.

Each time you depress the positive or

negative side “minus” and “plus”, the

time will either advance or decrease

respectively by one minute. If you press

and hold either side of the time button,

the time change will accelerate rapidly.

When you reach the correct time, release

the time button and the time will be set

into permanent memory.

Note: To ensure the time changes are

made, the ZSM will initiate a 30 second

user-stabilization time before making

changes to the ZSM operation mode.

Keypad Operation

Note: After toggling to the program screen,

the week is divided into seven days with

each day divided into four periods.

Therefore, 28 program settings are pos-

sible.

is installed and warmup options are

enabled.

During unoccupied periods, only the

desired room temperature setpoints are

entered. Each unoccupied period has a

heat and cool setpoint, and both setpoints

are offered during programming.

Blank temperature settings may also be

entered. When a setpoint is blank, the

program will default to the last setpoint of

its type. If there is no setpoint of its type,

the default setpoint is used. If all setpoints

in the time period are blank, the entire

time period is erased after exiting from

the program menu.

The ZSM has independent, seven day

programming:

• Each day can be programmed with

different times, temperatures, and

occupied status.

• Each day can be programmed with up

to four periods. Although four periods

are available each day, you can

program just one of the four.

• Each period can be programmed for

occupied or unoccupied.

To begin programming, follow these

steps:

• Determine which periods during the day

will be occupied and unoccupied.

• Write your daily schedule on the sheet

enclosed with the zone sensor.

• Enter your program by following the

steps below.

To program time periods and setpoints

for a day:

• Press the program button to enter

program mode.

• Press the day button to select first day to

be programmed.

• To set the “begin” time for the first

period of the day, press the minus or

plus keys.

• To set the temperature setpoint for that

period, use ↑ or ↓.

• Press the program button to move to

the next period for that day.

• To program time periods and setpoints

for the next day, press the day button.

• When finished, press and hold the

program button for two seconds to

return to the normal run mode.

Figure I-P-3. Display program menu screen

60 SCXG-SVX01B-EN

a temporary manual override menu. See

Figure I-P-4.

This mode overrides any number of

programmed setpoints through any of

the 28 programmed periods. After

entering setpoints and length of override

time, these settings are now used.

Keypad Operation for Temporary

Manual Override Menu

The keypad has the same function in

temporary manual override menu as in

all other menus, with a few exceptions:

• Depressing the day button will toggle

your ZSM between the day and hour

icon. See Figure I-P-4.

• Depressing the mode button will toggle

your ZSM between the heat and cool

icons and setpoints.

• Depressing the erase button will cancel

the override and return the ZSM to

normal run mode.

• Depressing the holdtemp or program

buttons while in the temporary manual

override menu will toggle your ZSM to

the temporary override mode. See

Figure I-P-5.

programmingInstallation

Note: Blank temperature settings may be

entered at any of the four daily periods.

When a setpoint is left blank and in an

occupied condition, the ZSM will default to

the last occupied setpoint. When a setpoint

is left blank and in an unoccupied condi-

tion, the ZSM will default to the last

unoccupied setpoint.

Temporary Manual Override

While in normal run mode, depressing

the hold temp button toggles the ZSM to

the temporary manual override menu.

The mode will override any number of

programmed setpoints through any of

the 28 programmed periods. After

entering setpoints and length of override

time, these new settings are used in place

of the setpoints programmed for normal

run mode.

Time Button

• While in the program menu, each time

you press and release the positive or

negative side of the time button, the

time will advance or decrease by ten

minute increments. If you press and

hold the positive or negative side

(“minus” and “plus” keys), the ZSM

will increment rapidly.

• When the display is in the normal run

mode, each time you press and release

the positive or negative side of the time

button (“minus” and “plus”keys), the

time will advance or decrease by one

minute. If you press and hold the

positive or negative side (“minus” and

“plus” keys), the ZSM will increment

rapidly.

Note: Blank temperature settings may be

entered at any of the four daily periods.

When a setpoint is left blank and in an

occupied condition, the ZSM will default to

the last occupied setpoint.

Keypad Lockout

If you simultaneously depress and hold

both the positive and negative sides of

the “minus” and “plus” keys for four

seconds, the lock icon will appear and all

keypad functions will lock out. If you

repeat this operation, the lock icon will

disappear and all keypad functions will be

available again.

• Keypad lockout applies only to normal

run mode and temporary manual

override mode.

Day Button

• In normal run mode, depressing the day

button will move the current day ahead.

• While in the program menu, depressing

the day button will move you through

the seven days of the week and allow

you to program temperature settings

for each of the four daily periods.

Erase Button

• Pressing the erase button while in

normal run mode will turn off the check

filter icon.

• Pressing the erase button while in the

program menu, will erase all time and

temperature setpoints of a given

period.

• The erase button will acknowledge the

failure buzzer (option 16) until 12:00 am.

Mode Button

• BAYSENS019 only: Pressing the mode

button toggles through all modes: off,

heat, cool, auto, and emer (HP unit).

• BAYSENS020 only: Pressing the mode

button while in normal run mode, or

temporary manual override run mode,

will toggle through both modes, off and

auto.

Fan Button

• The fan button allows you to toggle

between on and auto.

Up and Down Button Arrows

• Depressing ↑ or ↓ arrow while in normal

run mode will cause your ZSM to toggle

to the temporary manual override

menu.

• Depressing either ↑ or ↓ arrow while in

the program menu or temporary

override menu will cause the

temperature setpoint to advance or

decrease in one degree increments.

• Depressing and holding either the ↑ or ↓

arrow will cause the temperature

setting to increment rapidly.

Simultaneously depressing the ↑ or ↓

arrow for two seconds while in the

program menu or temporary override

menu will toggle the ZSM between an

occupied and unoccupied condition.

Holdtemp Button

While in normal run mode, depressing

the hold temp button toggles the ZSM to

Figure I-P-4. Temporary manual override menu

screen

Figure I-P-5. Override run mode screen

SCXG-SVX01B-EN 61

Temporary Override Run Mode

The temporary override run mode sends

setpoint data to the unit control module

(UCM) from the setpoint data entered in

the temporary manual override menu.

In temporary override run mode, most of

the keypad functions lock out with these

exceptions:

• The mode button still functions as in

normal run mode.

• The fan button still functions as in

normal run mode.

• Depressing the holdtemp button toggles

the ZSM between the temporary

manual override menu and override

run mode. (if no button is pressed for 20

seconds while in temporary manual

override menu, the ZSM exits to normal

run mode, ignoring the temporary

override settings.)

• Depressing either the ↑ or ↓ arrow while

in the override run mode will cause the

ZSM to toggle to the temporary manual

override menu.

• The erase button will turn off the check

filter icon if displayed.

• Simultaneously depressing and holding

the positive and negative sides of the

“minus” and “plus” for four seconds

will lock out the keypad.

• Time is not adjustable in this mode.

• The program button is disabled.

Keypad Operation for Temporary

Manual Override Menu

The keypad has the same function in

temporary manual override menu as in

all other menus, with a few exceptions:

• Depressing the holdtemp or program

buttons while in temporary manual

override menu will enter settings and

begin temporary manual override run

mode. See Figure I-P-6.

programmingInstallation

• Depressing the day button will toggle

the ZSM between the day and hour

icon.

• Depressing the mode button will toggle

the ZSM between the heat and cool

icons and setpoints.

• Depressing the erase button will cancel

the override and return the ZSM to

normal run mode.

• If no button is pressed for 20 seconds,

the ZSM exits temporary manual

override menu and enters the normal

run mode, ignoring the temporary

manual override menu settings.

Temporary Manual Override Run Mode

The temporary manual override run

mode sends setpoint data to the UCM

from the setpoint data entered in the

temporary manual override menu. See

Figure I-P-7.

In temporary manual override run mode,

most of the keypad functions lock out with

these exceptions:

• The mode button still functions as in

normal run mode.

• Depressing the holdtemp button toggles

the ZSM between temporary manual

override menu and temporary manual

override run mode. If no button is

pressed for 20 seconds, while in the

temporary manual override menu, the

ZSM exits to the normal run mode,

ignoring the temporary manual

override settings.

• Depressing either the up or down arrow

keys while in temporary manual

override run mode will cause the ZSM

to toggle to temporary manual override

menu.

• The erase button will turn off the check

filter icon if displayed.

• Simultaneously depressing and holding

the positive and negative sides of the

minus/plus key for four seconds will lock

out the keypad.

• Time is not adjustable in this mode.

Figure I-P-6. Temporary manual override menu

screen

62 SCXG-SVX01B-EN

Table I-P-1. Zone sensor BAYSENS019 option menu settings

option description value factory setting

1 morning warmup 0 = disabled 0

1 = enabled

2 economizer minimum 0 = disabled 1

position override 1 = enabled

3 temperature scale 0 = Fahrenheit 0

1 = enabled

4 supply air tempering 0 = disabled 0

1 = enabled

5 time clock 0 = 12 hours 0

1 = 24 hours

6 smart fan 0 = disabled 1

1 = enabled

7 intelligent temperature recovery 0 = disabled 0

1 = enabled

8 programmable days/week 0 = 7 days (M,T,W,T,F,S,S) 0

1 = 3 days (M-F, S, S)

2 = 2 days (M-F, S,S)

9 programmable periods/day 2,3,4 4

10 programmable fan operation 0 = disallowed 0

1 = allowed

11 remote sensor installed 0 = No 0

1 = Yes

12 check filter interval 0 = disabled 350

3000 to 50 in 50 hour

increments

13 display zone temperature 0 = no 1

1 = yes

14 keypad lockout enabled 0 = disabled 1

1 = enabled

15 initial time setting in temporary 1,2,3,4,5 3

override mode (hrs.)

16 buzzer options 0 = key press only 1

1 = key press & check filter

2 = key press, check filter,

and system failures

17 zone temperature calibration displays current temp. 0 offset

with any offsets

18 baud rate 0 = 1024 baud 1

1 = 1200 baud

19 CV or HP operation 0 = CV 0

1 = HP

20 default cooling setpoint 45 to 98°F 74°F

21 default heating setpoint 43 to 96°F 68°F

22 minimum cooling setpoint 45 to 98°F 45°F

23 maximum heating setpoint 43 to 96°F 96°F

programmingInstallation

Figure I-P-8. Typical option menu screen

Option Menu and Keypad Operation

The operation menu sets all

programmable options built into your

ZSM. All options are retained in

permanent EEPROM memory.

To access the option menu display,

simultaneously depress and hold the

mode button and program button for four

seconds.

The example in Figure I-P-8 shows option

15 displayed and indicates the initial timer

setting in the temporary override run

mode. The option value shown is in

hours, and value selected is five hours.

When the option menu displays, the only

active buttons are the ↑ or ↓ arrow and

the “minus” and “plus” button. The ↑ or

↓ arrow increment through the available

options by number (1-24), and the

“minus” and “plus” button toggles

through the various option values

associated with each option number. See

Table I-P-1.

Note: On both programmable zone sensor

options, changing either option 9 or 10 will

erase the current program. To avoid

reprogramming, set options 9 and 10

before programming.

Figure I-P-7. Temporary manual override run

mode screen

SCXG-SVX01B-EN 63

programmingInstallation

Table I-P-2. Zone sensor BAYSENS020 option menu settings

option description value factory

setting

1 morning warmup 0 = disabled 0

1 = enabled

2 economizer minimum 0 = disabled 1

position override 1 = enabled

3 temperature scale 0 = Fahrenheit 0

1 = enabled

4 heat installed 0 = no 0

1 = yes

5 time clock 0 = 12 hours 0

1 = 24 hours

6 hydronic heat 0 = no 0

1 = yes

7 daytime warmup 0 = disabled 0

1 = enabled

8 programmable days/week 0 = 7 days (M,T,W,T,F,S,S) 0

1 = 3 days (M-F, S, S

2 = 2 days (M-F, S,S)

9 programmable periods/day 2,3,4 4

10 remote sensor installed 0 = no 0

1 = yes

11 check filter interval 0 = disabled 350

3000 to 50 in 50 hour

increments

12 display zone temperature 0 = no 1

1 = yes

13 keypad lockout rnabled 0 = disabled 1

1 = enabled

14 initial time setting in temporary 1,2,3,4,5 3

override mode (hrs.)

15 buzzer options 0 = key press only 1

1 = key press & check filter

2 = key press, check filter,

and system failures

16 zone temperature calibration displays current temp. 0 offset

with any offsets

17 default cooling setpoint 45 to 98°F (unoccupied) 74°F

18 default heating setpoint 43 to 96°F (unoccupied) 68°F

19 default supply air cool 40 to 80°F (occupied) 55°F

20 default supply air heat 60 to 160°F 100°F

21 default warmup 50 to 90°F (occupied) 68°F

22 minimum cooling setpoint 45 to 98°F 45°F

23 maximum heating setpoint 43 to 96°F 96°F

24 minimum supply air cool 40 to 80°F (occupied) 40°F

25 maximum supply air heat 60 to 160°F 160°F

26 maximum warmup 50 to 90°F 90°F

Note: On both programmable zone sensor

options, changing either option 9 or 10 will

erase the current program. To avoid

reprogramming, set options 9 and 10

before programming.

Intelligent Copy

Note: Once you use Intelligent Copy, you

cannot use it again until you erase all

weekday and weekend time periods by

pressing ERASE for 5 seconds.

If your heating and cooling requirements

are the same for each day of the week,

and for each day of the weekend, your

ZSM is designed to employ Intelligent

Copy.

To program the five weekdays, Monday

through Friday, program only one

weekday. Likewise, to program the

weekend, Saturday and Sunday, pro-

gram only one day. After programming

one weekday and/or one weekend day,

Intelligent Copy automatically copies your

program to the other days.

To use Intelligent Copy:

1) Be sure to select the seven day

programming format in the Options

Menu. See Tables I-P-1 and I-P-2.

2) Be sure the entire program is blank.

3) Go to Program Menu.

4) Enter your setpoint parameters.

Intelligent Copy will automatically copy

these parameters to the other

weekdays.

5) Depress the DAY pushbutton until a

weekend day icon appears.

6) Enter setpoint parameters. Intelligent

Copy will automatically copy these

parameters to the other weekend day.

Remote Panel Indicator Signals From

UCM to ZSM

The unit control module (UCM) can send

four signals to the ZSM.

• Heat

• Cool

• On

• Service

Each of these four signals have three

different conditions. See Table I-P-3.

• Off

• On

• Flashing

Table I-P-3. UCM signal conditions

signal condition

heat on FlashingHEAT is ON and indicated by a solid HEAT icon in the

Display. Failure in the cooling system indicated by a flashing COOL

FAIL icon.

cool on FlashingCOOLING is ON and indicated by a solid COOL icon in the

Display. Failure in the cooling system indicated by a flashing

COOL FAIL icon.

on off FlashingSystem is OFF and indicated by a solid colon on the time of

on day display. System is ON and indicated by a flashing colon on

the time of day display. System is in TEST mode and indicated by a

flashing TEST icon.

service flashing ON System requires service and is indicated by a solid SERVICE

icon. There is a FAN failure indicated by a flashing SERVICE icon.

Note: There is no indication for a signal in the OFF condition. If option 16 is set to “2,” any flashing signals will

also give audible buzzer indication

64 SCXG-SVX01B-EN

programmingInstallation

Icon Descriptions

BAYSENS019 Icon Descriptions

Refer to Figure I-P-9 for the written

descriptions below.

1. The four periods of the day used only

during programming mode.

2. The seven days of the week used

during programming and in normal

mode to display the day (not current in

Program Menu).

3. Four digits used to display the time of

day in normal run mode. Also used in

Programming Menu and Temporary

manual Override Menu, and options

menu.

4. Time of day colon used on the time of

day clock. The colon blinks to indicate

the UCM system is functional.

5. AM and PM are used to indicate the

time of day when using a 12 hour clock.

AM and PM are not used when a 24

hour clock is selected.

6. DAYS and HOURS are used to set the

override timer period.

7. Displayed in temporary manual

OVERRIDE mode, and when setting the

override timer.

8. Only used when setting the override

timer.

Figure I-P-9. BAYSENS019 complete icon display

9. Displays the desired state of either

OCCUPIED or UNOCCUPIED.

10. The padlock symbol indicates that the

keyboard lockout is in effect.

11. This extends the mode selection box

in order to accommodate the

emergency heat mode on the ZSM heat

pump version.

12. Fan mode selection box.

13. Displayed in normal run mode when

displaying the actual room

temperature.

14. Displayed in option setting mode only.

15. Digits used to display temperature.

16. HEAT and COOL have two functions:

they indicate UCM status in normal run

mode and indicate which type of

setpoint is DESIRED during

programming and override setting.

17. Only used during programming and

override setting to indicate the

DESIRED setpoint temperature.

18. Flashes when check filter timer is

elapsed.

19. Flashing cooling fail status indicator.

20. Only used during UCP self-test mode.

21. Flashing service status indicator and

fan failure.

22. Flashing heating fail status indicator.

23. Operating MODE selection box.

SCXG-SVX01B-EN 65

programmingInstallation

Figure I-P-10. BAYSENS020 complete icon display

BAYSEN020 Icon Descriptions

Refer to Figure I-P-10 for the written

descriptions below.

1. The four periods of the day used only

during programming mode.

2. The seven days of the week used

during programming and in normal run

mode.

3. Four digits used to display the time of

day in normal run mode. Also used in

Programming Mode, override timer

setting menu, and options menu.

4. Time of day colon used on the time of

day clock. The colon blinks to indicate

the UCM system is functional.

5. AM and PM are used to indicate the

time of day when using a 12 hour clock.

AM and PM are not used when a 24

hour clock is selected.

6. DAYS and HOURS are used to set the

override timer period.

7. Displayed in temporary manual

OVERRIDE mode, and when setting the

override timer.

8. Only used when setting the override

timer.

9. Displays the desired state of either

OCCUPIED or UNOCCUPIED in the

Programming, Run, and Menu.

10. The padlock symbol indicates that the

keyboard lockout is in effect.

11. Operating mode selection box.

12. Displayed in normal run mode when

displaying the actual room

temperature.

13. Displayed in option setting mode only.

14. Digits used to display temperature.

15. HEAT and COOL have two functions:

they indicate UCM status in normal run

mode and indicate which type of

setpoint is DESIRED during

programming and override setting.

16. Only used during programming and

override setting to indicate the

DESIRED setpoint temperature.

17. Flashes when check filter timer is

elapsed.

18. Flashing cooling fail status indicator.

19. Only used during UCP self-test mode.

20. Flashing service status indicator and

fan failure.

21. Flashing heating fail status indicator.

22. Used in programming mode to set

HEAT SUPPLY AIR, COOL SUPPLY AIR,

and MORNING WARM-UP

temperatures.

66 SCXG-SVX01B-EN

Programming the Time Clock

Option

Setting the Time

Important: Depress the reset key before

beginning to set time and program.

1. Select military (24:00 hr.) or AM/PM

(12:00 hr.) time mode by depressing

and holding the “h” key while pressing

“+ 1h” key to toggle between military

and AM/PM. (AM appears in the display

when in AM/PM mode.)

2. Press and hold down “” key.

3. If setting the time when daylight

savings time is in effect, press “+ 1h”

key once (+ 1h will appear in display).

4. Set hour with “h” key. If AM or PM

does not appear in display, the unit is in

military time. See note above to

change display.

5. Set minutes with “m” key.

6. Press “Day” key repeatedly to the day

of the week. (1 is Monday, 7 is Sunday)

7. Release “” key, colon will begin

flashing.

Note: If keys h + or m + are kept depressed

for longer than 2 seconds, a rapid advance

of figures will result.

The “Digi 20” electronic time switch is

freely programmable for each day of the

week in one minute increments. For easy

and quick programming, the following 4

block programs are available:

• Monday through Sunday

• Monday through Saturday

• Monday through Friday

• Saturday and Sunday

Programming

Follow the instructions below for

programming the time clock.

1. Press “Prog.” key. 1234567 AM—:—

will appear in display. (Pressing “Prog.”

key again, display will show the number

of free programs “Fr 20”). Press again

to RETURN to 1st program.

2. Press “%” key, “~” ON symbol will

appear. Pressing the key again will

toggle to OFF “”. Select ON or OFF

for the program.

3. Press “h+” to select hour for switching

time.

4. Press “m+” to select minute for

switching time.

5. If the program is to occur every day of

the week, (24 hour time control) ignore

“Day” key and press “Prog.” key to

advance to program.

6. For 7 day time control, press “Day”

key. 1 2 3 4 5 6 (Monday through

Saturday) block of days appears in

display. Pressing “Day” key again, 1 2 3

4 5 (Monday through Friday) appears in

display. Repeated presses will cycle

through all days of the week and back

to 1 through 7 (Monday through

Sunday). Select day or block of days

desired.

7. Press “Prog.” key and repeat steps 2

through 6a to enter additional

programs of ON and OFF times. (Note

that more than one OFF time may be

programmed, enabling automatic

control or manual overrides.)

8. Press “” key to enter run mode.

To review and change programs:

1. To review a program at any time, press

“Prog.” key. Programs display in the

sequence they were entered with

repeated presses of “Prog.” key.

2. To change a program, select that

program as outlined in step 1. Enter the

time of day and days of week just as in

the programming steps above. The old

program is overwritten with the new

selections. Press “Prog.” to store the

new program.

3. To delete an individual program, select

the program as in step 1 and press “h”

and “m” keys until “—:—” appears in

the display. Press either “Prog.” or “¹”

key until “—:—” flashes. The program

is deleted after a few seconds.

Manual Override

While in the “run” mode (“” symbol is

displayed), pressing the “%” key will

reverse the load status (switch load off if

it is on, or switch it on if it is off). A hand

symbol appears in the display to indicate

the override is active. At the next

scheduled switching time, automatic time

control resumes, eliminating the override.

Pressing the “%” key a second time

“[~]” appears in the display indicating

the load is permanently on.

Pressing the “%” key a third time “[]”

appears in the display indicating the load

is permanently off.

Pressing the “%” key a fourth time

returns to automatic, “%” appears in the

display.

All days shown in the respective blocks

will switch on (or off) at the selected hour

and minute.

programmingInstallation

SCXG-SVX01B-EN 67

Unit Startup Procedures





WARNING

Hazardous Voltage w/Capaci-

tors!

Disconnect all electric power, including

remote disconnects before servicing.

Follow proper lockout/tagout proce-

dures to ensure the power cannot be

inadvertently energized. For variable

frequency drives or other energy storing

components provided by Trane or others,

refer to the appropriate manufacturer’s

literature for allowable waiting periods

for discharge of capacitors. Verify with an

appropriate voltmeter that all capacitors

have discharged. Failure to disconnect

power and discharge capacitors before

servicing could result in death or serious

injury.

Note: For additional information regard-

ing the safe discharge of capacitors, see

PROD-SVB06A-EN or PROD-SVB06A-FR.

Pre-Startup Checklist

1. Verify electrical connections are tight.

2. Water-cooled: Access the liquid line

service valves. Verify the liquid line

service valve is open at startup.

Note: Each compressor suction line

contains a low pressure sensor that will

shut the compressor down in low pressure

situations. See Table O-SO-2.

3. Ensure system components are

properly set and installed.

4. Inspect all ductwork and connections.

5. Remove compressor and fan

assembly tie down bolts. On 20 - 38 ton

units, do not remove the fan assembly

shipping blocks. Tie down bolts if the fan

speed is 750 rpm or less.

6. Ensure fan rotation is in the direction of

the arrow on the fan housing. If it is

incorrect, verify the incoming power

phasing is correct. Switch wires on the

fan contact to properly phase fan if

necessary.

7. Check the fan belt condition and tension.

Adjust the tension if belts are floppy or

squeal continually. Replace worn or

fraying belts in matched sets.

Startup





WARNING

Live Electrical Components!

During installation, testing, servicing and

troubleshooting of this product, it may

be necessary to work with live electrical

components. Have a qualified licensed

electrician or other individual who has

been properly trained in handling live

electrical components perform these

tasks. Failure to follow all electrical safety

precautions when exposed to live

electrical components could result in

death or serious injury.

NOTICE

Compressor Damage!

Never manually or automatically pump

down system below 7 psig. This will

cause the compressor to operate in a

vacuum and result in compressor

damage.

To start the unit, complete the following

steps in order.

1. Apply power to the unit. Close the unit

disconnect switch option.

2. Make sure the liquid line service valves

are open on water cooled units.

3. Adjust setpoints at the HI.

Note: A sufficient cooling load must be

visible to refrigerant circuit controls for

mechanical refrigeration to operate. If

necessary, temporarily reduce the dis-

charge air setpoint to verify the refrigeration

cycle operation.

4. Check voltage at all compressor

terminals to ensure it is within 10% of

nameplate voltage.

5. Check voltage imbalance from these

three voltage readings at each

compressor. Maximum allowable

voltage imbalance, phase to phase is

2%.

6. Check amp draw at compressor

terminals. RLA and LRA is on the unit

nameplate.

startupInstallation

7. Measure amp draw at evaporator fan

motor terminals. FLA data is on the

motor nameplate.

8. After the system has stabilized (15 to 30

minutes), check and record operating

pressures and temperatures for all

circuits.

Using the startup log on the following

pages, establish nominal conditions for

consistent measurements as follows:

• Leaving air greater than 60°F

• Entering air temperature = 70 to 90°F

• Entering water temperature > 60°F

• Inlet guide vanes at least halfway open

With all compressors running at full load:

1. Compute superheat from the suction

line pressure and temperature at the

compressor on each circuit. Adjust the

thermal expansion valve settings if

necessary. Superheat should be

between 12 and 17°F.

2. Inspect refrigerant flow in the liquid line

sight glass. Flow should be smooth and

even, with no bubbles once the system

has stabilized.

Normal startup will occur provided that

Tracer Summit is not controlling the

module outputs or the generic BAS is not

keeping the unit off. To prevent Tracer

Summit from affecting unit operation,

remove Tracer wiring and make required

changes to setpoint and sensor sources.

Operating & Programming Instructions

Reference the

IntelliPak Self-Contained

Programming Guide, PKG-SVP01B-EN,

for available unit operating setpoints and

instructions.

A copy ships with each unit.

For units with the VFD option, reference

the installer guide that ships with each

VFD.

68 SCXG-SVX01B-EN

Installation

Startup Log

Complete this log at unit startup.

Unit: ____________________________ Unit Location: _________________________________________

Unit Voltage: __________ __________ __________

A B C

Evaporator:

evaporator fan motor horsepower: __________ evaporator fan motor amps: __________ __________ __________

A B C

evaporator fan rpm (actual): ____________________

evaporator system static (from test and balance report or actual readings):

supply duct static: __________

return duct static: __________

evaporator air conditions with both compressors operating:

entering: leaving:

dry-bulb °F: __________ dry-bulb °F: __________

wet-bulb °F: __________ wet-bulb °F: __________

evaporator system cfm (test and balance sheet or actual tested): __________

________________________________________________________________________________________________________________________

Compressor Amp Draw:

circuit A: __________ __________ __________ circuit B: __________ __________ __________

A B C A B C

circuit C: __________ __________ __________ circuit D: __________ __________ __________

A B C A B C

circuit E: __________ __________ __________ circuit F: __________ __________ __________

A B C A B C

suction pressure, psig: circuit A: __________ circuit B: __________ circuit C: __________ circuit D: __________

circuit E: __________ circuit F: __________

discharge pressure, psig: circuit A: __________ circuit B: __________ circuit C: __________ circuit D: __________

circuit E: __________ circuit F: _________

super heat °F: circuit A: __________ circuit B: __________ circuit C: __________ circuit D: __________

circuit E: __________ circuit F: _________

liquid line pressure, psig: circuit A: __________ circuit B: __________ circuit C: __________ circuit D: __________

circuit E: __________ circuit F: _________

sub cooling °F: circuit A: __________ circuit B: __________ circuit C: __________ circuit D: __________

circuit E: __________ circuit F: _________

startup

SCXG-SVX01B-EN 69

Installation startup

___________________________________________________________________________________________________________________________

Water Cooled Units:

Circuit A:

entering water temperature °F: __________ leaving water temperature °F: __________

entering water pressure, psig: __________ leaving water pressure, psig: __________

Circuit B:

enter water temperature °F: __________ leaving water temperature °F: __________

entering water pressure, psig: __________ leaving water pressure, psig: __________

Circuit C:

entering water temperature °F: __________ leaving water temperature °F: __________

entering water pressure, psig: __________ leaving water pressure, psig: __________

Circuit D:

enter water temperature °F: __________ leaving water temperature °F: __________

entering water pressure - psig: __________ leaving water pressure, psig: __________

Circuit E:

enter water temperature °F: __________ leaving water temperature °F: __________

entering water pressure - psig: __________ leaving water pressure, psig: __________

Circuit F:

enter water temperature °F: __________ leaving water temperature °F: __________

entering water pressure - psig: __________ leaving water pressure, psig: __________

___________________________________________________________________________________________________________________________

Air Cooled Units:

(data taken from outside condensing unit)

voltage: __________ __________ __________ amp draw: __________ __________ __________

A B C A B C

entering air temperature °F: __________ leaving air temperature °F: __________

refrigerant pressures at condenser, psig: __________/ __________ sub cooling at condenser °F: __________

70 SCXG-SVX01B-EN

Operation

general

information

Binary outputs

• V.O. relay

Points List - TracerTM LCI-I Module

Constant Volume (CV) Points

Binary inputs

• Airside economizer enable/disable

• Condensor type (air or water cooled)

• Condensor water flow status

• Emergency shutdown

• Local fan switch enable/disable

• Mechanical cooling lockout

• Mechanical heating lockout

• Mixed air temperature

• Occupancy

• Occupancy override

• Occupancy sensor

Binary outputs

• Airside economizer status

• Alarm status

• Compressor on/off status

• Condensor circuit information

• Condensor water pump status

• Waterside economizer status

Analog inputs

• Airside economizer dry bulb setpoint

• Airside economizer minimum setpoint

• Building static pressure input

• Maintenance required time

• Occupancy bypass time

• Outdoor air damper minimum position

setpoint

• Outdoor air relative humidity

• Outdoor air temperature

• Unit start delay time setpoint

• Zone temperature

• Zone temperature setpoint

• Zone temperature setpoint (default)

• Zone temperature setpoint limits

• Zone temperature setpoint offsets

• Zone temperature setpoint shift

Analog outputs

• Alarm message

• Building static pressure status

•Condensor saturated refrigerant temp

• Condensor water temperature

• Cooling output status

• Effective occupancy

• Exhaust fan status

• Heating output status

• Heating/cooling mode

• Morning warm up sensor temperature

• Outdoor air damper position

• Outdoor air enthalpy

• Outdoor air relative humidity

• Return air temperature

• Supply air temperature

• Supply fan status

• Unit status mode

• Zone CO2

• Zone relative humidity

Variable Air Volume (VAV) Points

Binary inputs

• Airside economizer enable/disable

• Condensor water flow input

• Emergency override

• Local fan switch enable/disable

• Mechanical cooling lockout

• Mechanical heating lockout

• Occupancy

Binary outputs

• Airside economizer status

• Alarm status

• Compressor on/off status

• Condensor circuit information

• Condensor type (water or air cooled)

• Condensor waterflow status

• Condensor water pump status

Analog inputs

• Airside economizer dry bulb setpoint

• Airside economizer minimum position

• Building static pressure input

• Building static pressure setpoint

• Daytime warm up setpoint

• Daytime warm up terminate setpoint

• Maintenance required time

• Occupancy bypass time

• Outdoor air damp min position setpoint

• Outdoor airflow minimum setpoint

• Outdoor air relative humidity

• Outdoor air temperature

• Supply air cooling setpoint

• Supply air cooling setpoint (default)

Analog outputs

• Building static pressure status

• Alarm message

• Condensor saturated refrigerant temp.

• Condensor water temperature

• Condensor water temp (local)

• Cooling output status

• Exhaust fan status

• Heating output status

• Heating/cooling mode

• Mixed air temperature

• Morning warm up sensor temperature

• Outdoor air damper position

• Outdoor air enthalpy

• Outdoor air flow

• Outdoor air relative humidity status

• Outdoor air temperature status

• Return air temperature

Points List

-

RTM Module

Binary inputs

• Emergency stop

• External auto/stop

• Unoccupied/occupied

• Dirty filter

• VAV changeover with hydronic heat

Binary outputs

• VAV box drive max (VAV units only)

• CV unoccupied mode indicator (CV units

only)

• Alarm

• Fan run request

• Water pump request (water-cooled only)

Analog input

• Airside economizer damper minimum

position

Analog output

• Outside air damper actuator

Heat Module:

• Analog output

Points List - GBAS Module

Binary inputs

• Demand limit contacts

Binary outputs

• Dirty filter relay

• Refrigeration fail relay

• Heat fail relay

• Supply fan fail relay

• Active diagnostics

Analog inputs

• Occupied zone cooling setpoint

• Occupied zone heating setpoint

• Unoccupied zone cooling setpoint

• Unoccupied zone heating setpoint or

minimum outside air flow setpoint

• Supply air cooling setpoint

• Supply air heating setpoint

• Supply air static pressure setpoint

Points List - ECEM Module

Analog inputs

• Return air temperature

• Return air humidity

In addition, units with a VOM have:

Binary inputs

• VOM mode A, unit off

• VOM mode B, pressurize

• VOM mode C, exhaust

• VOM mode D, purge

• VOM mode E, purge w/duct pressure control

SCXG-SVX01B-EN 71

Unit Control Components

The Modular Series IntelliPak self-

contained unit is controlled by a

microelectronic control system that

consists of a network of modules. These

modules are referred to as unit control

modules (UCM). In this manual, the

acronym UCM refers to the entire control

system network.

These modules perform specific unit

functions using proportional/integral

control algorithms. They are mounted in

the unit control panel and are factory

wired to their respective internal compo-

nents. Each module receives and

interprets information from other unit

modules, sensors, remote panels, and

customer binary contacts to satisfy the

applicable request; i.e., economizing,

mechanical cooling, heating, ventilation.

Following is a detailed description of each

module’s function.

RTM Module Board - Standard

on all Units

The RTM responds to cooling, heating,

and ventilation requests by energizing the

proper unit components based on

information received from other unit

modules, sensors, remote panels, and

customer supplied binary inputs. It

initiates supply fan, exhaust fan, exhaust

damper, inlet guide vane positioning or

variable frequency drive output, and

airside economizer operation based on

that information.

Reference the RTM points list.

Note: Emergency stop and external auto/

stop, stop the unit immediately, emergency

stop generates a manual reset diagnostic

that must be reset at the unit human

interface. External auto-stop will return the

unit to the current operating mode when

the input is closed, so this input is auto

reset.

RTM Remote Economizer Minimum

Position

The remote minimum position

potentiometer, BAYSTAT023A, provides

a variable resistance (0-270 ohms) to

adjust the economizer minimum position

from 0 to 100% when connected to the

economizer remote minimum position

input of the RTM. The RTM must be

selected as the source for economizer

minimum position. If the RTM is the

selected source for economizer minimum

position, and

if a valid resistance per

Table O-GI-1 is provided to the RTM

remote minimum position input,

the OA

cfm compensation function will not

operate, even if enabled. “Default” is the

only possible source for economizer

minimum position when using the OA

cfm compensation function.

Table O-GI-1. Economizer remote minimum

position input resistance

input economizer

resistance min. position

0 - 30 ohms 0 %

30 - 240 ohms 0-100 % (linear)

240 - 350 ohms 100 %

> 350 ohms N/A *

* Note: A resistance greater than 350 ohms is

assumed to be an open circuit. The system will use

the default minimum position value.

RTM Analog Outputs

The RTM has two 0-10 vdc outputs: one

for the inlet guide vane option and one for

the economizer option. These outputs

provide a signal for one or two damper

actuators. There are no terminal strip

locations associated with these wires.

They go directly from pins on the RTM

circuit board to the actuator motor.

RTM Binary Outputs

The RTM has an output with pressure

switch proving inputs for the supply fan.

There is a 40 second delay from when

the RTM starts the supply fan until the fan

proving input must close. A fan failure

diagnostic will occur after 40 seconds.

This is a manual reset diagnostic, and all

heating, cooling, and economizer

functions will shut down. If this proving

input is jumped, other nuisance

diagnostics will occur. If the proving input

fails to close in 40 seconds, the

economizer cycles to the minimum

position. This is a manual reset

diagnostic. External control of the fan is

not recommended.

VAV Drive Max Output

This is a single-pole, double-throw relay

rated at a maximum voltage of 24 vac,

two amps. The relay contacts of this relay

switch when theunit goes from the

occupied mode to the unoccupied mode

bymeans of the occupied binary input.

The contacts will stay switched during the

unoccupied and morning warmup mode.

They will return to the position shown on

the unit wiring diagram when the unit

returns to the occupied mode. This binary

output signals the VAV boxes or other

terminal devices to go full open.

RTM Alarm Relay

This is a single pole, double throw relay

rated at a maximum voltage of 24 vac,

two amps max. Relay contacts can be

programmed from the unit human

interface. This relay can be programmed

to pick up on any one or group of

diagnostics from the unit human

interface.

Status/Annunciator Output

The status annunciator output is an

internal function within the RTM module

on CV and VAV units. It provides:

a. diagnostic and mode status signals to

the remote panel (LEDs) and to the

Human Interface.

b. control of the binary alarm output on

the RTM.

c. control of the binary outputs on the

GBAS module to inform the customer

of the operational status and/or

diagnostic conditions.

Occupied/Unoccupied Inputs

There are four ways to switch to

occupied/unoccupied:

1. Field-supplied contact closure

hardwired binary input to the RTM

2. Programmable night setback zone

sensor

3. Tracer Summit

4. Factory-mounted time clock

VAV Changeover Contacts

These contacts are connected to the RTM

when daytime heating on VAV units with

internal or external hydronic heat is

required. Daytime (occupied) heating

switches the system to a CV unit

operation. Refer to the unit wiring

diagram for the field connection terminals

in the unit control panel. The switch must

be rated at 12 ma @ 24 VDC minimum.

External Auto/Stop Switch

A field-supplied switch may be used to

shut down unit operation. This switch is a

binary input wired to the RTM. When

opened, the unit shuts down immediately

and can be cancelled by closing the

switch. Refer to the unit wiring diagrams

(attached to the unit control panel) for

proper connection terminals. The switch

Operation

general

information

72 SCXG-SVX01B-EN

Table O-GI-2. RTM sensor resistance vs. temperature

temperature, °F resistance, Ω ohms temperature, °F resistance, Ω ohms

-40 346.1 71 11.60

-30 241.7 72 11.31

-20 170.1 73 11.03

-10 121.4 74 10.76

-5 103.0 7 5 10.50

0 87.56 7 6 10.25

5 74.65 7 7 10.00

10 63.8 78 9.76

15 54.66 79 6.53

20 46.94 80 9.30

25 40.40 85 8.25

30 34.85 90 7.33

35 30.18 100 5.82

40 26.22 105 5.21

45 22.85 110 4.66

50 19.96 120 3.76

55 17.47 130 3.05

60 15.33 140 2.50

65 13.49 150 2.05

66 13.15 160 1.69

67 12.82 170 1.40

68 12.50 180 1.17

69 12.19 190 0.985

70 11.89 200 0.830

general

information

Table O-GI-4. RTM resistance value vs. system operating mode

resistance

applied to RTM mode CV units VAV units

input terminals, ohms fan mode system mode system mode

2320 auto off off

4870 auto cool

7680 auto auto auto

10,770 on off

13,320 on cool

16,130 on auto

19,480 auto heat

27,930 on heat

Note: Mode boundaries are 1000 to 40,000 ohms. Other boundaries are equal to the midpoint between the

nominal mode resistance.

Table O-GI-3. RTM setpoint analog inputs

cooling or heating setpoint input, °F cooling setpoint input, °F

(using RTM as zone temp. source) (using RTM as supply air temp. source) resistance, Ω

ohms

40 40 1084

45 45 992

50 50 899

55 55 796

60 60 695

65 65 597

70 70 500

75 75 403

80 80 305

NA 85 208

N A 9 0 111

must be rated for 12 ma @ 24 VDC

minimum. This input will override all VOM

inputs, if the VOM option is on the unit.

Occupied/Unoccupied Contacts

To provide night setback control if a

remote panel

with night setback

was not

ordered, install a field-supplied contact.

This binary input provides the building’s

occupied/unoccupied status to the RTM. It

can be initiated by a time clock, or a

building automation system control

output. The relay’s contacts must be rated

for 12 ma @ 24 VDC minimum. Refer to

the appropriate wiring diagrams

(attached to the unit control panel for the

proper connection terminals in the unit

control panel.

Emergency Stop Input

A binary input is provided on the RTM

board for installation of a field-supplied

normally closed (N.C.) switch to use

during emergency situations to shut

down all unit operations. When open, an

immediate shutdown occurs. An

emergency stop diagnostic enters the

human interface and the unit will require

a manual reset. Refer to the unit wiring

diagrams (attached to the unit control

panel for the proper connection

terminals. The switch must be rated for

12 ma @ 24 VDC minimum. This input

will override all VOM inputs, if the VOM

option is on the unit.

VAV Box Option

To interlock VAV box operation with

evaporator fan and heat/cool modes,

wire the VAV boxes/air valves to VAV box

control connections on the terminal block.

Supply Duct Static Pressure Control

The RTM relies on input from the duct

pressure transducer when a unit is

equipped with IGV or VFD to position the

IGV or set the supply fan speed to

maintain the supply duct static pressure

to within the static pressure setpoint

deadband.

RTM Sensors

RTM sensors include: zone sensors with

or without setpoint inputs and modes,

supply air sensor, duct static pressure,

outside air temperature, outside air

humidity, airflow proving, and dirty filter.

Operation

SCXG-SVX01B-EN 73

Compressor Module (MCM -

Standard on all Units

The compressor module, (single circuit

and multiple circuit) energizes the

appropriate compressors and condenser

fans upon receiving a request for

mechanical cooling. It monitors the

compressor operation through feedback

information it receives from various

protection devices.

Human Interface Module -

Standard on all Units

The human interface (HI) module enables

the operator to adjust the operating

parameters for the unit using it's 16-key

keypad on the human interface panel.

The HI panel provides a two line, 40

character, clear language (English,

Spanish, or French) LCD screen with unit

status information and menus to set or

modify operating parameters. It is

mounted in the unit’s main control panel

and accessible through the unit’s control

panel door.

Remote Human Interface

Module Option

The optional remote-mount human

interface (RHI) panel has all the functions

of the unit-mounted version except for

service mode. To use a RHI, the unit must

be equipped with an optional

interprocessor communications bridge

(IPCB). Model number digit 32 (=2)

indicates if the ICPB was ordered with the

unit. If not, contact your local Trane

representative to order an ICPB kit for

field installation. The RHI can be located

up to 1,000 feet (304.8 m) from the unit. A

single RHI can monitor and control up to

four self-contained units if each one

contains an IPCB. The IPCB switches must

be set as SW1- off, SW2 - off, and SW3 -

on.

Interprocessor Communications Board •

Option used with RHI

The interprocessor communication board

expands communications from the unit's

UCM network to a remote human

interface panel. DIP switch settings on the

IPCB module for this application are;

switches 1 and 2 “off,” switch 3 “on.”

Waterside Module - Standard

on all water-cooled units

The waterside module (WSM) controls all

water valves based on unit configuration.

In addition, the WSM monitors waterflow

proving and the following temperatures:

• entering water

• entering air low

• mixed air

• entering condenser water

• refrigerant circuit 3:

• saturated condenser

• evaporator frost

• motor winding

• refrigerant circuit 4:

• condenser

• evaporator

• motor winding

Cooling Tower Interlock

To interlock condenser pump/tower with

cooling operation, wire the cooling tower

to an external 115 volt control power

source, to ground, and to control terminal

block. Normally open/closed contacts are

provided.

Heat Module

The heat module is standard on all units

with factory-installed heat. It controls the

unit heater to stage up and down to bring

the temperature in the controlled space

to within the applicable heating setpoint.

Also, it includes a freezestat, morning

warmup, and heating outputs.

Ventilation Override Module

(VOM) Option

The ventilation override module can be

field-configured with up to five differnent

override sequences for ventilation

override control purpose. When any one

of the module’s five binary inputs are

activated, it will initiate specified functions

such as; space pressurization, exhaust,

purge, purge with duct pressure control,

and unit off.

Once the ventilation sequences are

configured, they can be changed unless

they are locked using the HI. Once locked,

the ventilation sequences cannot be

unlocked.

The compressors and condenser fans

disable during the ventilation operation. If

more than one ventilation sequence

activates, the one with the highest priority

(VOM “A”) begins first, with VOM “E”

having lowest priority and beginning last.

A description of the VOM binary inputs

follows below.

UNIT OFF sequence “A”

When complete system shut down is

required, the following sequence can be

used.

• Supply fan – off

• Supply fan VFD – off (0 Hz)

• Inlet guide vanes – closed

• Outside air dampers – closed

• Heat – all stages – off, modulating heat

output at 0 vdc

• Occupied/Unoccupied output – de-

energized

• VO relay – energized

• Exhaust fan (field-installed) - off

• Exhaust damper (field-installed) - closed

PRESSURIZE sequence “B”

This override sequence can be used if a

positively pressured space is desired

instead of a negatively pressurized space.

• Supply fan – on

• Supply fan VFD – on (60 Hz)

• Inlet guide vanes/VAV boxes – open

• Outside air dampers – open

• Heat – all stages – off, hydronic heat

output at 0 vdc

• Occupied/ unoccupied output -

energized

• VO relay - energized

• Exhaust fan (field-installed) - off

• Exhaust damper (field-installed) - closed

EXHAUST sequence “C”

With the building’s exhaust fans running

and the unit’s supply fan off, the

conditioned space becomes negatively

pressurized. This is desirable for clearing

the area of smoke when necessary; i.e.

from an extinguished fire, to keep smoke

out of areas that were not damaged.

• Supply fan – off

• Supply fan VFD – off (0 Hz)

• Inlet guide vanes – closed

• Outside air dampers – closed

• Heat – all stages – off, hydronic heat

output at 0 vdc

• Occupied/Unoccupied output – de-

energized

• VO relay – energized

• Exhaust fan (field-installed) - on

• Exhaust damper (field-installed) - open

general

information

Operation

74 SCXG-SVX01B-EN

Figure O-GI-2. Velocity pressure transducer/

solenoid assembly

PURGE sequence “D”

This sequence can purge the air out of a

building before coming out of unoccupied

mode of operation in a VAV system. Also,

it can be used to purge smoke or stale air.

• Supply fan – on

• Supply fan VFD – on (60 hz)

• Inlet guide vanes/VAV boxes – open

• Outside air damper – open

• Heat – all stages – off, modulating heat

output at 0 vdc

• Occupied/Unoccupied output –

energized

• VO relay – energized

• Exhaust fan (field-installed) - on

• Exhaust damper (field-installed) - open

PURGE with duct pressure control “E”

This sequence can be used when supply

air control is required for smoke control.

• Supply fan – on

• Supply fan VFD – on (if equipped)

• Inlet guide vanes – controlled by supply

air pressure control function with

supply air pressure high limit disabled

• Outside air dampers – open

• Heat – all stages – off, hydronic heat

output at 0 vdc

• Occupied/unoccupied output – energized

• VO relay – energized

• Exhaust fan (field-installed) - on

• Exhaust damper (field-installed) - open

Note: Each system (cooling, exhaust,

supply air, etc.) within the unit can be

redefined in the field for each of the five

sequences, if required. Also the definitions

of any or all of the five sequences may be

locked into the software by simple key

strokes at the human interface panel. Once

locked into the software, the sequences

cannot be changed.

Trane IntelliPak Lon-Talk

Communication Module (LCI-I

Option used on units with

Trane ICSTM or 3rd party

Building AutomationSystems)

The LonTalk Communication Interface

module expands communications from

the unit UCM network to a Trane Tracer

SummitTM or a 3rd party building

automation system, utilizing LonTalk, and

allows external setpoint and

configuration adjustment and monitoring

of status and diagnostics.

general

information

Exhaust/Comparative

Enthalpy (ECEM ) Module -

Option used on units with

comparative enthalpy option

The exhaust/comparative enthalpy

module receives information from the

return air humidity sensor, and the RTM

outside air temperature sensor and

outside air humidity sensor, the outside

air humidity sensor and temperature

sensor to utilize the lowest possible

enthalpy level when considering

economizer operation. In addition, it

receives space pressure information to

maintain the space pressure within the

setpoint control band. Refer to the Figure

O-GI-1 for humidity vs. voltage values.

Ventilation Control Module

(VCM) - Available only with

Traq™ Damper Option

The ventilation control module (VCM) is

located in the airside economizer section

of the unit and linked to the unit’s UCM

network. Using a velocity pressure

transducer/solenoid (pressure sensing

ring) in the fresh air section allows the

VCM to monitor and control fresh air

entering the unit to a minimum airflow

setpoint. See Figure O-GI-2 for a detail

view of the velocity pressure transducer/

solenoid assembly.

An optional temperature sensor can be

connected to the VCM to enable control

of a field installed fresh air preheater.

Also, a field-provided CO2 sensor can be

connected to the VCM to control CO2

reset. The reset function adjusts the

minimum cfm upward as the CO2

concentrations increase. The maximum

effective (reset) setpoint value for fresh

air entering the unit is limited to the

system’s operating cfm. Table O-GI-5 lists

the minimum outside air cfm vs. input

voltage.

Table O-GI-5. Minimum outside air setpoint

w/VCM module and Traq™ sensing

Unit Input Volts CFM

SXWG 20 0.5 - 4.5 vdc 6,350-8,500

SXWG 25 0.5 - 4.5 vdc 7,250-10,625

SXWG 30 0.5 - 4.5 vdc 7,250-12,750

SXWG 35 0.5 - 4.5 vdc 7,250-14,875

SXRG 20 0.5 - 4.5 vdc 7,250-8,500

SXRG 25 0.5 - 4.5 vdc 7,250-10,625

SXRG 32 0.5 - 4.5 vdc 7,250-13,600

Figure O-GI-1. ECEM relative humidity vs.

voltage

Operation

SCXG-SVX01B-EN 75

Generic Building Automation

System Module Option

The generic building automation system

module (GBAS) provides broad control

capabilities for building automation

systems other than Trane’s Tracer

system. A field provided potentiometer

or a 0-5 vdc signal can be applied to any

of the inputs of the GBAS to provide the

following points:

GBAS Analog Inputs

Four analog inputs that can be configured

to be any of the following:

(1) occupied zone cooling

(2) unoccupied zone cooling

(3) occupied zone heating

(4) unoccupied zone heating

(5) SA cooling setpoint

(6) SA heating setpoint

(7) space static pressure setpoint

(8) SA static pressure setpoint

GBAS Binary Outputs

Five binary outputs to provide

diagnostics, signaling up to five alarms.

Each of the five (5) relay outputs can be

mapped to any/all of the available

diagnostics. Each output contains a dry

N.O. and N.C. contact with a VA rating of 2

amps at 24 VAC.

GBAS Binary Input

One binary input for the self-contained

unit to utilize the demand limit function.

This function is operational on units with a

GBAS and is used to reduce electrical

consumption at peak load times. Demand

limiting can be set at either 50% or

100%. When demand limiting is needed,

mechanical cooling and heating (with

field-provided 2-stage electric heat only)

operation are either partially (50%), or

completely disabled (100%) to save

energy. The demand limit definition is

user definable at the HI panel. Demand

limit binary input accepts a field supplied

switch or contact closure. When the need

for demand limiting has been

discontinued, the unit’s cooling/heating

functions will again become fully enabled.

GBAS Communication (Analog Inputs)

The GBAS accepts external setpoints in

the form of analog inputs for cooling,

heating, supply air pressure. Refer to the

unit wiring diagram for GBAS input

wiring and the various desired setpoints

with the corresponding DC voltage

inputs.

general

information

Any of the setpoint or output control

parameters can be assigned to each of

the four analog inputs on the GBAS

module. Also, any combination of the

setpoint and/or output control param-

eters can be assigned to the analog

inputs through the HI. To assign the

setpoints apply an external 0-5 vdc

signal:

1. directly to the signal input terminals, or

2. to the 5 vdc source at the GBAS

module with a 3-wire potentiometer.

Note: There is a regulated 5 vdc output on

the GBAS module that can be used with a

potentiometer as a voltage divider. The

recommended potentiometer value is 1000-

100,000 ohms.

The setpoints are linear between the

values shown in Table O-GI-6 on page 66.

Reference Table O-GI-7 on page 66 for

corresponding input voltage setpoints.

Following are formulas to calculate input

voltage or setpoint. SP = setpoint, IPV =

input voltage.

If the setpoint range is 50-90°F:

IPV = (SP - 50) (0.1) + 0.5

SP = [(IPV - 0.5)/0.1] + 50

If the setpoint range is 40-90°F:

IPV = (SP - 40)(0.8) + 0.5

SP = [(IPV - 0.5)/0.08] + 40

If the setpoint range is 40-180°F:

IPV = (SP - 40)(0.029) + 0.5

SP = [(IPV - 0.5)/0.029] + 40

If the static pressure range is 0.03-0.3

iwc:

IPV = (SP - 0.03)(14.8) + 0.5

SP = [(IPV - 0.5)/14.8] + 0.03

If the static pressure range is 0.0-5.0 iwc:

IPV = (SP)(0.8) + 0.5

SP = [IPV/(0.8 + 0.5)]

GBAS Demand Limit Relay (Binary Input)

The GBAS allows the unit to utilize the

demand limit function by using a

normally open (N.O.) switch to limit the

electrical power usage during peak

periods. Demand limit can initiate by a

toggle switch closure, a time clock, or an

ICS control output. These contacts must

be rated for 12 ma @ 24 VDC minimum.

When the GBAS module receives a

binary input signal indicating demand

limiting is required, a command initiates

to either partially (50%) or fully (100%)

inhibit compressor and heater operation.

This can be set at the HI using the setup

menu, under the “demand limit definition

cooling” and “demand limit definition

heating” screens. A toggle switch, time

clock, or building automation system

control output can initiate demand

limiting.

If the cooling demand limit is set to 50%,

half of the cooling capacity will disable

when the demand limit binary input

closes. The heating demand limit defini-

tion can only be set at 100%, unless the

unit has field-provided two-stage electric

heat. In that case, if the heating demand

limit is set to 50%, half or one stage of

heating disables when the demand limit

binary input closes. If the demand limit

definition is set to 100%, then all cooling

and/or heating will disable when the

demand limit input closes.

GBAS Diagnostics (Binary Outputs)

The GBAS can signal up to five alarm

diagnostics, which are fully mappable

through the setup menu on the HI. These

diagnostics, along with the alarm output

on the RTM, allow up to six fully

mappable alarm outputs.

Each binary output has a NO and NC

contact with a rating of two amps at 24

VAC. The five binary outputs are factory

preset as shown on the unit wiring

diagram (on the unit control panel door).

However, these outputs can be field

defined in a variety of configurations,

assigning single or multiple diagnostics to

any output.

For a complete listing of possible diagnos-

tics, see the

IntelliPak Self-Contained

Programming Guide, PKG-SVP01B-EN

.

For terminal strip locations, refer to the

unit wiring diagram for the GBAS.

Operation

76 SCXG-SVX01B-EN

Table O-GI-6. GBAS analog input setpoints

control parameter signal range setpoint range

occupied zone cooling setpoint 0.5 to 4.5 vdc 50 to 90°F

(CV units only)

unoccupied zone cooling setpoint 0.5 to 4.5 vdc 50 to 90°F

(CV and VAV)

occupied zone heating setpoint 0.5 to 4.5 vdc 50 to 90°F

(CV units only)

unoccupied zone heating setpoint 0.5 to 4.5 vdc 50 to 90°F

(CV and VAV)

supply air cooling setpoint 0.5 to 4.5 vdc 40 to 90°F

(VAV units only)

supply air hydronic heating setpoint 0.5 to 4.5 vdc 40 to 180 F

(VAV units only)

space static pressure setpoint 0.5 to 4.5 vdc 0.03 to 0.30 IWC

supply air pressure setpoint 0.5 to 4.5 vdc 0.0 to 5.0 IWC

(VAV units only)

Notes: 1. Input voltages less than 0.5 vdc are considered as 0.5 vdc input signal is lost, the setpoint will

“clamp” to the low end of the setpoint scale. No diagnostic will result from this condition.

2. Input voltages greater than 4.5 vdc are considered to be 4.5 vdc.

3. The actual measured voltage is displayed at the HI.

Table O-GI-7. GBAS input voltage corresponding setpoints

temp. temp. temp temp

volts °F volts ° F volts ° F volts °F

0.5 50 1.6 60 2.6 70 2.7 80

0.6 51 1.7 61 2.7 71 2.8 81

0.7 52 1.8 62 2.8 72 2.9 82

0.8 53 1.9 63 2.9 73 3.0 83

0.9 54 2.0 64 3.0 74 3.1 8 4

1.0 55 2.1 6 5 3.1 75 3.2 85

1.1 56 2.2 6 6 3.2 76 3.3 86

1.2 57 2.3 6 7 3.3 77 3.4 87

1.3 58 2.4 6 8 3.4 78 3.5 88

1.5 59 2.5 6 9 3.5 79 3.6 89

general

information

Operation

SCXG-SVX01B-EN 77

Waterside Components

Waterside components consist of water

piping, water valves, water flow switch

option, water cooled condensers (SXWF

only), and the economizer option.

Water Purge

This user-definable feature allows the

user to select a purge schedule to

automatically circulate water through the

economizer and condensers periodically

during non-operational times. This allows

fresh chemicals to circulate in waterside

heat exchangers. This feature is on all

units and is defined at the HI.

Water Piping Options

Water piping is factory-installed with left-

hand connections on units without a

waterside economizer. Units can be

ordered with either basic piping or

intermediate piping. Also, units with

waterside economizers can be set for

either variable or constant water flow at

the HI. See Figures O-GI-3, O-GI-4, and O-

GI-5 for detailed piping configuration

information.

With compatible piping configurations,

the unit can be configured to provide:

1. Constant water flow with basic or

intermediate piping or

2. Variable water flow (head pressure

control) with intermediate piping only.

Constant water flow is for condenser

pumping systems that are not capable of

unloading the water-pumping system.

Variable water flow maximizes energy

saving by unloading the water pumping

system.

Basic Water Piping

This option is available on units without a

waterside economizer and with

condenser water applications above 54°F

(12.2°C) that do not require condensing

pressure control. Left hand water

connections and piping are extended to

the unit exterior. Manifold piping is

factory installed.

Intermediate Water Piping

This option provides condensing

temperature control when the unit is

configured (user defined at the HI) for

variable water flow with or without a

waterside economizer. A two-way

modulating control valve is wired and

installed in the unit to maintains a specific

range of water temperature rise through

the condenser when entering fluid

temperature is less than 58°F (15°C). This

option allows the compressor to operate

with entering fluid temperature down to

35°F (2°C). The minimum valve position

to maintain minimum condenser flow

rates is user-defined at the HI. This valve

drives closed if the unit shuts down or if a

power failure occurs.

Water Flow Switch Option

A water flow switch is factory installed in

the condenser water pipe within the unit.

Whenever the flow switch detects a

water flow loss prior to or during

mechanical cooling, compressor

operation locks out and a diagnostic code

displays. If water flow is restored, the

compressor operation automatically

restores.

Water-Cooled Condensers

Units that are set up for variable water

flow will modulate a water valve to

maintain a user-defined condensing

temperature setpoint. Condensing

temperature will be referenced utilizing

factory installed sensors located at each

condenser.

Table O-GI-8. Condenser water piping

connection sizes

unit size inlet pipe outlet pipe

SXWG 20, 25, 2 1/2 NPT 2 1/2 NPT

30, 32, 35

Waterside Economizer Option

The waterside economizer option takes

advantage of cooling tower water to

either precool the entering air to aid the

mechanical cooling process or, if the

water temperature is low enough,

provide total system cooling. Waterside

economizing enables when the unit’s

entering water temperature is below the

unit’s entering mixed air temperature by

a minimum of 4°F plus the economizer’s

approach temperature. The approach

temperature default is 4°F. Waterside

economizing disables when the unit’s

entering water temperature is not below

the unit’s entering mixed air temperature

by at least the water economizer

approach temperature. The approach

temperature defaults to 4°F. The

economizer acts as the first stage of

general

information

cooling. If the economizer is unable to

maintain the supply air setpoint, the unit

control module brings on compressors as

required to meet the setpoint.

The waterside economizer includes a coil,

modulating valves, controls, and piping

with cleanouts. The coil construction is ½-

inch (13 mm) OD seamless copper tubes

expanded into aluminum fins. The

evaporator and economizer coils share a

common sloped (IAQ) drain pan. Drain

pan options are either galvanized or

stainless steel, and are insulated and

internally trapped.

The waterside economizer coil is avail-

able with either a two or four row coil,

with no more than 12 fins per inch. The

tubes are arranged in a staggered

pattern to maximize heat transfer. The

coil has round copper supply and return

headers with removable cleanout and

vent plugs. The optional mechanical

cleanable economizer has removable

cast iron headers to allow easy mechani-

cal cleaning of the tubes. The waterside

working pressure is rated for 400 psig

(2758 kPa).

Waterside Economizer Flow Control

Units equipped with a waterside

economizer can be set from the human

interface panel for variable or constant

water flow.

Constant Water Flow

Two-way modulating control shutoff

valves are wired, controlled, and installed

in the unit. One valve is located in the

economizer’s water inlet, and the other is

in the condenser bypass water inlet.

When the waterside economizer enables,

the two-way valves modulate to maintain

the discharge air temperature setpoint.

As the economizer valve opens, the

condenser bypass valve closes, and vice

versa. Full water flow is always

maintained through the condensers. Both

valves will close in the event of a power

failure.

Variable Water Flow

Two-way modulating control shutoff

valves are wired, controlled, and installed

in the unit. One valve is located in the

economizer’s water inlet, and the other is

in the condenser water inlet. When the

economizer valve is active, the

condenser bypass valve closes. The

Operation

78 SCXG-SVX01B-EN

Condenser 1

Condenser 2

V2

Condenser 2

V1

Economizer

Condenser 1

Condenser 2

V2

Figure O-GI-3. Basic water piping, constant

water flow

Figure O-GI-4. Intermediate water piping,

variable water flow

Figure O-GI-5. Intermediate piping with waterside economizer, variable or

constant water flow

general

information

economizer valve modulates, thus water

flow through the unit modulates. If the

water is cool enough for economizing, but

mechanical cooling is also required, the

economizer valve fully opens to establish

full water flow through the condensers.

Whenever the water is too warm for

economizing and there is a call for

cooling, the economizer valve fully closes

and the bypass valve fully opens,

establishing full water flow through the

condensers. Full water flow is always

maintained through the condensers

when mechanical cooling is required.

Both valves close whenever cooling is

not required, and in the event of a power

failure.

Operation

Condenser 1

SCXG-SVX01B-EN 79

Unit Airside Components

The unit’s air delivery system consists of

dampers, enthalpy switch option, airside

economizer option, filters, low ambient

sensors, and factory mounted single or

double wall plenums.

Supply Air Fan

The unit has a single supply fan that runs

at a constant speed. However, the fan

may have the IGV or VFD option that

modulates airflow based on supply air

temperature control. Pressing the stop

key on the HI will turn the supply fan off.

The fan is on continuously when a CV unit

is in occupied mode and except when a

unit is in the night heat/morning warmup

mode. During the night heat and setback

mode the fan cycles on and off in

response to a call for heat. See Table O-

GI-9 for available fan horsepower.

Low Entering Air Temperature Sensor

This is standard on all units with a

hydronic coil or waterside economizer. It

can also be ordered as an option.

A thermostat limit switch is factory

mounted on the unit’s entering air side

with a capillary tube serpentine across

the coil face. If the temperature falls

below 35°F (2°C), the fan shuts down and

the waterside economizer and/or

hydronic heat valve options open to allow

full water flow. The heat output also

energizes. A manual reset is required.

The low entering air temperature

setpoint is adjustable at the HI.

High Duct Temperature Thermostat

A factory-supplied temperature limit

switch with reset element detects the

supply air duct temperature. This sensor

should be field-installed downstream

from the unit’s discharge in the supply air

duct. If the supply air duct temperature

exceeds 240°F (115.6°C), the unit shuts

down and displays a diagnostic. A

manual reset is required at the unit. The

high duct temperature can be adjusted at

the thermostat.

Dirty Filter Sensor Option

A factory installed pressure switch

senses the pressure differential across

the filters. When the differential pressure

exceeds 0.9-inches (23 mm) WG, contact

closure occurs and the HI will display a

diagnostic. The unit will continue to run

until you replace the air filters.

A field installed indicator device may be

wired to relay terminals to indicate when

filter service is required. Contacts are

rated at 115 VAC and are powered by a

field supplied transformer.

Low Ambient Sensor (Air-Cooled Units)

The low ambient sensor is field-installed

on air-cooled units. Position it in a location

subject to ambient temperatures only

and not exposed to direct sunlight or

exhaust fans.

The low pressure cutout initiates based

on the ambient temperature. A time

delay on the low pressure cutout initiates

for ambient temperatures between 50

(zero minutes) and 0°F (10 minutes). This

helps to prevent nuisance low pressure

cutout trips.

Inlet Guide Vane Option

Inlet guide vanes (IGV’s) are driven by a

modulating 0-10 vdc signal from the RTM

module. A pressure transducer

measures duct static pressure, and the

IGVs modulate to maintain the supply air

static pressure within an adjustable user-

defined range. The range is determined

by the supply air pressure setpoint and

supply air pressure deadband, which are

set through the HI panel.

IGV assemblies installed on the supply

fan inlet regulate fan capacity and limit

horsepower at lower system air require-

ments. When in any position other than

full open, the vanes pre-spin the air in the

same direction as the supply fan rotation.

As the vanes approach the full-closed

position, the amount of “spin” induced by

the vanes increases at the same time

that intake airflow and fan horsepower

diminish. The IGVs will close when the

supply fan is off.

Supply Air Static Pressure Limit

The opening of the IGVs and VAV boxes

coordinate during unit startup and

transition to/from occupied/unoccupied

modes to prevent supply air duct

overpressurization. However, if for any

reason the supply air pressure exceeds

the user-defined supply air static

pressure limit set at the HI panel, the

supply fan/VFD shuts down and the IGVs

close. The unit will attempt to restart, up

to three times. If the overpressurization

condition still occurs on the third restart,

the unit shuts down and a manual reset

diagnostic sets and displays at the HI.

Variable Frequency Drive Option

The variable frequency drive (VFD) is

driven by a modulating 0-10 vdc signal

from the RTM module. A pressure

transducer measures duct static

pressure, and the VFD adjusts the fan

speed to maintain the supply air static

pressure within an adjustable user-

defined range. The range is determined

by the supply air pressure setpoint and

supply air pressure deadband, which are

set at the HI panel.

VFDs provide supply fan motor speed

modulation. The drives will accelerate or

decelerate as required to maintain the

supply air static pressure setpoint.

VFD with Bypass

Bypass control is an option that provides

full nominal airflow in the event of drive

failure. The user must initiate the bypass

mode at the HI panel. When in bypass

mode, VAV boxes need to be fully open.

The self-contained unit will control

heating and cooling functions to maintain

setpoint from a user-defined zone sensor.

Supply air static pressure limit is active in

this mode.

For more detailed information on VFD

operation, reference the VFD technical

manual that ships with the unit.

Airside Economizer Option

Units with the airside economizer option

are equipped with the necessary control

sequences to use outside air for the first

general

information

Operation

80 SCXG-SVX01B-EN

stage of cooling, in occupied or

unoccupied mode and when ambient

conditions are favorable for economizing.

Inherent in the unit controller is the ability

to suppress the setpoint below the

normal unit setpoint. This allows the

building to improve comfort levels when

possible, and at the same time, optimize

building mechanical cooling operation for

peak operating efficiency. An outside air

temperature and relative humidity

sensor are provided to allow monitoring

of reference enthalpy and are field

installed.

If the unit has the ECEM board, econo-

mizer operation enables when the

outside air enthalpy is less than 25 BTU’s/

lb. default (adjustable 19-28 BTU’s/lb).

During occupied mode, the outside air

damper opens to 15% (adjustable 0-

100% at the HI) for ventilation purposes.

Also, the ability to alter the outside air

damper position to compensate for VAV

supply air modulation is inherent in the

unit controls, and can be enabled by the

operator.

If the unit does not have an ECEM board,

it will economize when the O/A tempera-

ture falls below the O/A economizer

setpoint.

The mixing box fabrication is galvanized

steel. Opposed low leak damper blades

are fabricated from galvanized steel and

rotate on rustproof nylon bushings. A

factory installed 24V modulating spring

return actuator controls both damper

positions.

When outdoor conditions are not suitable

for economizer cooling, the enthalpy

control disables the economizer function

and permits the outdoor air damper to

open only to the minimum position.

On water-cooled units, compressor

operation lockout will not occur at low

ambient air temperatures. However,

lockout will still occur via low condenser

water temperature.

The outdoor air dampers drive fully

closed whenever the supply air fan is off,

provided there is power to the unit.

Comparative Enthalpy Control

Comparative enthalpy controls the

economizer operation and measures

temperature and humidity of both return

air and outside air to determine which

general

information

source has lower enthalpy. This allows

true comparison of outdoor air and return

air enthalpy by measurement of outdoor

air and return air temperatures and

humidities. A factory-installed control

board, with field-installed outside and

return air temperature and relative

humidity sensors, allows monitoring of

outside and return air.

Note: If comparative enthalpy is not

ordered, the standard method is to

compare outdoor air enthalpy with the

fixed reference enthalpy. The reference

enthalpy is set through the human interface

panel.

Units with comparative enthalpy control

are equipped with the necessary control

sequences to allow using outside air for

the first stage of cooling, in occupied or

unoccupied mode and when ambient

conditions are favorable for economizing.

Inherent in the unit controller is the ability

to suppress the setpoint below the

normal unit setpoint. This allows the

building to improve comfort levels when

possible, and at the same time, optimize

building mechanical cooling operation for

peak operating efficiency.

Economizer operation enables when the

outside air enthalpy is 3 BTu/lb less than

the return air enthalpy. During occupied

mode, the outside air damper opens to

15% (adjustable 0-100%) for ventilation

purposes. Also, the ability to alter the

outside air damper position to compen-

sate for VAV supply air modulation is

inherent in the unit controls, and can be

enabled by the operator.

The mixing box fabrication is galvanized

steel. Opposed low leak damper blades

are fabricated from galvanized steel and

rotate on rustproof nylon bushings. A

factory installed 24V modulating spring

return actuator controls both damper

positions.

Airside Economizers with TraqTM Damper

Outside air enters the unit through the

TraqTM damper assembly and is

measured by velocity pressure flow

rings. The velocity pressure flow rings

are connected to a pressure transducer/

solenoid assembly, which compensates

for temperature swings that could affect

the transducer. The ventilation control

module (VCM) utilizes the velocity

pressure input, the RTM outdoor air

temperature input, and the minimum

outside air cfm setpoint to modify the

volume (cfm) of fresh air entering the unit

as the measured airflow deviates from

setpoint.

When the optional preheat temperature

sensor is installed at the auxiliary

temperature on the VCM and the preheat

function is enabled, the sensor will

monitor the combined (averaged) fresh

air and return air temperatures. As this

mixed air temperature falls below the

preheat actuate temperature setpoint,

the VCM activates the preheat binary

output to control a field-installed heater.

The output deactivates when the tem-

perature rises 5°F above the preheat

actuate temperature setpoint.

Using a field-installed CO2 sensor with

CO2 reset enabled, as the CO2 concentra-

tion increases above the CO2 reset start

value, the VCM modifies the minimum

outside air cfm setpoint to increase the

amount of fresh air entering the unit. The

setpoint adjusts upward until reaching the

CO2 maximum reset value. The maxi-

mum effective (reset) setpoint value for

fresh air is limited to the system’s

operating cfm. As the CO2 concentration

decreases, the effective (reset) setpoint

value adjusts downward toward the

minimum outside air cfm setpoint. See

Figure O-GI-6 for an airflow cfm vs. CO2

concentration curve.

Standard Two-Position Damper Interface

Units with the two-position damper

interface are provided with a 0-10 VDC

control output suitable for controlling a

field-provided modulating actuator. In

occupied mode, the output drives to the

maximum position.

Airside Economizer Interface

Units with airside economizer interface

are equipped with the necessary control

sequences to allow using outside air for

the first stage of cooling, in occupied or

unoccupied mode and when ambient

conditions are favorable for economizing.

Inherent in the unit controller is the ability

to suppress the setpoint below the

normal unit setpoint. This allows the

building to improve comfort levels when

possible, and at the same time, optimize

building mechanical cooling operation for

Operation

SCXG-SVX01B-EN 81

peak operating efficiency. An outside air

temperature and relative humidity

sensor are provided for field installation

to monitor reference enthalpy.

Economizer operation enables when the

outside air enthalpy is less than 25 BTu/lb

(adjustable 19-28 BTu/lb.). During

occupied mode, the outside air damper

opens to 15% (adjustable 0-100%) for

ventilation purposes. Also, the ability to

alter the outside air damper position to

compensate for VAV supply air

modulation is inherent in the unit controls,

and can be enabled by the operator. An

analog 2-10 VDC output (adjustable (0-10

VDC) is provided to modulate the field-

provided 30 second damper actuators

(adjustable 1-255 seconds).

Airside Economizer Interface with

Comparative Enthalpy

Units with airside economizer interface

and comparative enthalpy are equipped

with the necessary control sequences to

allow using outside air for the first stage

of cooling, in occupied or unoccupied

mode and when ambient conditions are

favorable for economizing. Inherent in the

unit controller is the ability to suppress

the setpoint below the normal unit

setpoint. This allows the building to

improve comfort levels when possible,

and at the same time, optimize building

mechanical cooling operation for peak

operating efficiency. A factory-installed

control board, with outside and return air

temperature and relative humidity

sensors, are provided for monitoring

outside and return air. The sensors are

field installed. Economizer operation

enables when the outside air enthalpy is

3 BTU’s/lb. less than the return air

enthalpy. During occupied mode, the

outside air damper opens to 15%

(adjustable 0-100%) for ventilation

purposes. Also, the ability to alter the

outside air damper position to

compensate for VAV supply air

modulation is inherent in the unit

controls, and can be enabled by the

operator. An analog 2-10 VDC output

(adjustable (0-10 VDC) is provided to

modulate the field-provided 30-second

damper actuators (adjustable 1-255

seconds).

Figure O-GI-6. CO

2

reset function, outside air vs. CO

2

general

information

Air-Cooled Condensers

Model SXRF units are designed for use

with the remote air-cooled condenser,

model CXRC. For more information, see

the air-cooled condenser Installation,

Owner, and Diagnostic Manual,

CXRC-

SVX01A-EN.

Condenser fans will stage per a user-

defined setting. If the condenser is

equipped with head pressure control (air

modulation on last stage of condenser

capacity), the condenser airflow will

modulate to maintain condensing

temperature setpoint. Condensing

temperature is determined by sensors

located at each condenser coil.

Operation

82 SCXG-SVX01B-EN

Input Devices and System

Functions

Following are basic input device and

system function descriptions used within

the UCM network on IntelliPak self-

contained units. Refer to the unit wiring

diagrams for specific connections.

Water Purge

NOTICE

Proper Water Treatment!

The use of untreated or improperly

treated water in coils may result in

scaling, erosion, corrosion, algae or

slime. It is recommended that the

services of a qualified water treatment

specialist be engaged to determine what

water treatment, if any, is required. Trane

assumes no responsibility for equipment

failures which result from untreated or

improperly treated water or saline or

brackish water.

During the unoccupied mode, water-

cooled units will periodically circulate

water through the condensers and

waterside economizer if the user has

enabled the purge function at the HI. The

water purge function circulates water to

introduce fresh water-treatment

chemicals and help prevent water

stagnation. The number of hours between

each periodic purge, or purge duration, is

user-defined at the HI between 1-999

hours. If the periodic purge timer expires

while the unit is in occupied mode, it will

wait for the next available unoccupied

time before initiating water purge.

Contrary, if a request for cooling occurs

during a purge sequence, purge will

terminate and cooling will commence.

Compressor Circuit Breakers

The compressors are protected by circuit

breakers that interrupt the compressor

power supply if the current exceeds the

breakers “must trip” value. During a

request for compressor operation, if the

compressor module (MCM or SCM)

detects a problem outside of it’s normal

parameters, it turns any operating

compressor(s) on that circuit off, locks

out all compressor operation for that

circuit, and initiates a manual reset

diagnostic.

Compressor Motor Winding Thermostats

A thermostat is embedded in the motor

windings of each compressor. Each

thermostat opens if the motor windings

exceed approximately 221°F. The

thermostat resets automatically when the

winding temperature decreases to

approximately 181°F. Rapid cycling, loss

of charge, abnormally high suction

temperatures, or the compressor running

backwards could cause the thermostat to

open. During a request for compressor

operation, if the compressor module

detects a problem outside of it's normal

parameters, it turns any operating

compressor(s) on that circuit off, locks

out all compressor operation for that

circuit, and initiates a manual reset

diagnostic.

Low Pressure Control

Low pressure (LP) control is

accomplished using a binary input device.

LP cutouts are mounted on the suction

lines near the compressors. The LP

control contacts close when the suction

pressure exceeds 27 ± 4 psig. If the LP

control is open when a compressor

starts, none of the compressors on that

circuit will operate. They are locked out

and a manual reset diagnostic initiates.

The LP cutouts open if the suction

pressure approaches 7 ± 4 psig. If the LP

cutout opens after a compressor starts,

all compressors operating on that circuit

will turn off immediately and will remain

off for a minimum of three minutes.

If the LP cutout trips four consecutive

times during the first three minutes of

operation, the compressors on that circuit

will lock out and a manual reset diagnos-

tic initiates.

Evaporator Temperature Sensor

Frostat™

The evaporator temperature sensor is an

analog input device used to monitor

refrigerant temperature inside the

evaporator coil to prevent coil freezing. It

is attached to the suction line near the

evaporator coil with circuits 1 and 2

connected to the SCM/MCM and circuits

3 and 4 connected to the WSM. The coil

frost cutout temperature is factory set at

30°F. It is adjustable at the HI from 25-35°F.

The compressors stage off as necessary

to prevent icing. After the last

compressor stages off, the compressors

will restart when the evaporator

temperature rises 10°F above the coil

frost cutout temperature and the

minimum three minute “off” time

elapses.

Saturated Condenser Temperature

Sensors

The saturated condenser temperature

sensors are analog input devices. They

are mounted inside a temperature well

located on a condenser tube bend on air-

cooled units, and in the condenser shell

on water-cooled units. The sensors

monitor the saturated refrigerant

temperature inside the condenser coil

and are connected to the SCM/MCM for

circuits 1 and 2 (air or water cooled), and

WSM for circuits 3 and 4 (only water-

cooled).

Head Pressure Control

Head pressure control is accomplished

using two saturated refrigerant

temperature sensors on air-cooled units

and up to four sensors on water-cooled

units.

Air-cooled units: During a request for

compressor operation when the con-

densing temperature rises above the

lower limit of the control band, the

compressor module (SCM/MCM)

sequences condenser fans on. If the

operating fans cannot bring the condens-

ing temperature to within the control

band, more fans turn on. As the satu-

rated condensing temperature ap-

proaches the lower limit of the control

band, fans sequence off. The minimum

on/off time for condenser fan staging is

5.2 seconds. If the system is operating at

a given fan stage below 100% for 30

minutes the saturated condensing

temperature is above the efficiency

check point setting, a fan stage will be

added. If the saturated condensing

temperature falls below the efficiency

check point setting, fan control remains at

the present operating stage. If the fan

stage cycles four times within a 10

minute period, the lower limit tempera-

ture is redefined as being equal to the

lower limit minus the temporary low limit

suppression setting. The unit will utilize

this new low limit temperature for one

hour to reduce condenser fan short

cycling.

general

information

Operation

SCXG-SVX01B-EN 83

Water-cooled: Units without WSE, the

condenser valve modulates to maintain

an average saturated condenser tem-

perature. Units with WSE, if economizing

and mechanical cooling is necessary the

economize valve will sacrifice free

cooling and modulate to maintain

condensing saturated temperature. If not

economizing, the condenser valve will

modulate to maintain condensing

saturated temperature.

Water-cooled units without head pres-

sure control will lock out mechanical

cooling at entering condenser water

temperatures below 54°F. Mechanical

cooling will resume when the entering

condenser water temperature exceeds

58°F.

Low Ambient Control (Air-Cooled Units

Only)

The low ambient modulating output on

the compressor module is functional on

all units with or without the low ambient

option. When the compressor module

stages up to it's highest stage (stage 2 or

3 depending on unit size), the modulating

output is 100% (10 VDC). When the

control is at stage 1, the modulating

output (0-10 VDC) controls the saturated

condensing temperature to within the

programmable condensing temperature

low ambient control point.

Low Ambient Compressor Lockout (Air-

Cooled Units Only)

The low ambient compressor lockout

utilizes an analog input device. When the

system is configured for low ambient

compressor lockout, the compressors will

not operate if the temperature of the

outside air falls below the lockout

setpoint. When the temperature rises 5°F

above the lockout setpoint, the

compressors will operate. The setpoint

for units without the low ambient option is

50°F. For units with the low ambient

option, the setpoint is 0°F. The setpoints

are adjustable at the human interface

panel.

Return Air Temperature Sensor

The return air temperature sensor is an

analog input device used with a return

humidity sensor on units with the

comparative enthalpy option. The sensor

monitors the return air temperature and

compares it to the outdoor temperature

to establish which temperature is best

suited to maintain cooling requirements.

It is mounted in the return air path and

connected to the ECEM.

Supply Fan Circuit Breaker, Fuses, and

Overloads

The supply fan motor is protected by

either circuit breakers fuses or a

combination of fuses and overloads,

dependent upon unit configuration.

Circuit breakers are used on units

without a VFD. They will trip and interrupt

the motor power supply if the current

exceeds the breaker trip value. The RTM

shuts all system functions off when

detecting an open fan proving switch.

Units with a VFD have fuses to protect

the VFD and motor. Units with a VFD w/

bypass have fuses to protect VFD circuit

and overloads to protect the motor when

in bypass.

Supply Air Temperature Low Limit

The supply air temperature low limit

function uses the supply air temperature

sensor input to modulate the economizer

damper to the minimum position if the

supply air temperature falls below the

occupied heating setpoint temperature.

Supply Air Temperature Sensor

The supply air temperature sensor is an

analog input device. It monitors the

supply air temperature for supply air

temperature control, supply air

temperature reset, supply air

temperature low limiting, and supply air

tempering. It is mounted in the supply air

discharge section of the unit and

connected to the RTM.

Supply Airflow Proving Switches

This is binary input device used on units

to signal the RTM when the supply fan is

operating. It is mounted in the supply fan

section and is connected to the RTM.

During a request for fan operation and if

the differential switch opens for 40

consecutive seconds, compressor

operation turns off, heat operation turns

off, the request for supply fan operation is

turns off and locks out, IGV option closes,

economizer damper option closes, and a

manual reset diagnostic initiates.

Low Entering Air Protection Device

(LEATPD)

The low entering air protection device

(LEATPD) is a binary input on units with

hydronic heat or a waterside economizer.

It is optional on water-cooled units.

If the LEATPD is on a unit with factory-

installed heat, it is mounted in the heat

section and connected to the heat

module. If the entering air temperature to

the heating coil falls to 40°F, the normally

open contacts on the LEATPD close and

cause the following events:

a. the hydronic heat actuator fully opens.

b. the supply fan turns off

c. the outside air damper closes

d. the SERVICE light at the remote zone

sensor option turns on.

e. a LEATPD diagnostic displays at the

human interface panel.

If the LEATPD is on a water-cooled unit

without factory-installed heat, it is wired

to the WSM. It will trip if the entering

water temperature falls to 34°F, open the

economizer valve, and energize the

pump output.

High Duct Temp Thermostat Option On

Units with an LCI-I

The high duct temperature thermostats

are binary input devices used on units

with a Trane communication interface

module (Tracer/LCI-I). They provide a high

limit unit shutdown and require a manual

reset. The thermostats are factory set to

open if the supply air temperature

reaches 240°F, or the return air

temperature reaches 135°F. Once tripped,

the thermostat requires a manual reset.

Reset by pressing the sensor’s reset

button when the air temperature

decreases approximately 25°F below the

cutout point.

Filter Switch

The filter switch is a binary input device

that measures the pressure differential

across the unit filters. It is mounted in the

filter section and connected to the RTM. A

diagnostic SERVICE signal displays at the

remote panel if the pressure differential

across the filters is at least 0.5” w.c. The

contacts automatically open when the

pressure differential across the filters

decrease to 0.4” w.c. The switch

differential is field adjustable between

0.17” to 5.0” w.c. ± 0.05 “.

High Duct Static Switch Option

The high duct static switch is field-

mounted in the ductwork or plenums

with smoke dampers. It will cause a

manual reset diagnostic if the duct static

exceeds the pre-set static limit. The static

limit is adjustable at the HI.

general

information

Operation

84 SCXG-SVX01B-EN

Control Sequences of

Operation

Occupied/Unoccupied Switching

There are four ways to switch occupied/

unoccupied:

(1) Night setback zone sensor

(2) Field-supplied contact closure

(hardwired binary input to RTM)

(3) Tracer Summit

(4) Factory-mounted time clock

Field Supplied Occupied/Unoccupied

Input on the RTM

This input accepts a field supplied switch

or contacts closure, such as a time clock,

with a rating of 12 mA at 24 VDC

minimum.

Tracer Summit System

The Tracer Summit system can control

the occupied/unoccupied status of the

self-contained unit.

Factory Mounted Time Clock

A time clock can control the

occupied/unoccupied status of the

self-contained unit.

Unoccupied Sequence of

Operation

The unoccupied mode helps conserve

energy during times when a building is

usually unoccupied. When in unoccupied

mode, the unit will control to the

unoccupied setpoints (usually a lower

Figure O-SO-1. Typical cycling morning warmup cycle

sequence of

operation

heating setpoint and higher cooling

setpoint). Setpoints can be programmed

at the HI, Tracer Summit, or the night

setback zone sensor.

The unit enters the unoccupied mode

when the RTM receives a closed signal

on the unoccupied input for more than

five seconds.

For units with supply air temperature

control entering unoccupied mode, the

following sequence will occur:

• Heating/cooling functions cease and the

economizer option closes fully. The

supply fan shuts down for proper cool-

down time of the heat exchanger.

However, the supply fan may remain

on for a short period of time.

• After the supply fan shuts down, the

occupied/unoccupied relay energizes

and the IGV option fully opens. Also, the

VAV box stroke time begins. The VAV

box stroke time is field adjustable to

allow time for VAV boxes to go to the

full open airflow position.

• After the max VAV box stroke time

expires and the IGV’s are fully open, the

supply fan, economizer (if enabled),

compressors, and heat are enabled to

satisfy the unoccupied zone

temperature setpoints.

Note: Unoccupied economizer operation

can be enabled or disabled at the HI or

using Tracer Summit.

Operation

SCXG-SVX01B-EN 85

sequence of

operation

is reached. Next a 60 minute timer

begins. If the building load reaches the

MWU ventilation setpoint, or the 60

minutes expire, whichever is first, the

airside economizer will control to the

minimum position. MWU will end when

the zone temperature rises above the

MWU terminate setpoint.

Timed Override Activation - ICS™

This function is operational whenever the

unit’s RTM module is used as the zone

temperature sensor source, which can be

set at the HI panel. When this function is

initiated by the push of the override

button on the zone sensor, the unit will

switch to the occupied mode. Unit

operation (occupied mode) during timed

override is terminated by a signal from

Tracer.

Timed Override Activation - Non-ICS

This function is active whenever the unit’s

RTM module board is selected as the

zone temperature source, which can be

set at the human interface panel. When

this function is initiated by the push of the

override button on the zone sensor, the

unit will switch to the occupied mode.

Automatic cancellation of the timed

override mode occurs after three hours

of operation.

VAV Drive Max Output

This is a single-pole, double-throw relay

rated at a maximum voltage of 24 vac,

two amps max. The relay contacts of this

relay switch when the unit goes from the

occupied mode to the unoccupied mode

by means of the unoccupied binary input,

night setback zone sensor, or Tracer

Summit. The contacts will stay switched

during the unoccupied and morning

warmup mode. They will return to the

position shown on the unit wiring

diagram when the unit returns to the

occupied mode. The intent of this binary

output is to signal the VAV boxes or other

terminal devices to go to a full open

airflow position.

For units without volume control entering

unoccupied mode, the following se-

quence will occur:

• The occupied/unoccupied relay ener-

gizes and the economizer option fully

closes.

• The fan mode is set to auto and the unit

will control to the unoccupied zone

temperature setpoints.

With MWU enabled at the HI, if the zone

temperature is below the MWU setpoint,

the unit enters the MWU mode.

Morning Warmup

This feature can be enabled at the HI, and

can be used with factory or field-installed

heat. If MWU is not required disable the

function in the setup menu at the HI.

MWU transitions the zone from

unoccupied to occupied. It will heat until

the MWU setpoint is met. The unit is then

released to occupied mode. Supply duct

static pressure is maintained during this

sequence. MWU can be set (at the HI) to

function as either full or cycling capacity.

Full Capacity Morning Warmup (MWU)

Full capacity morning warmup uses full

heating capacity to heat the zone as

quickly as possible. Full heating capacity

is provided until the morning warmup

setpoint is met. At this point, the unit is

released to daytime mode.

Cycling Capacity Morning Warmup

(MWU)

Cycling capacity morning warmup

provides a more gradual heating to

overcome “building sink” as the zone is

heated. Normal zone temperature control

with varying capacity is used to raise the

zone temperature to the MWU zone

temperature setpoint. This method of

warmup is used to overcome the

“building sink” effect.

Reference Figure O-SO-1 on page 73 for

a pictorial explanation of the cycling

MWU sequence. Cycling capacity MWU

will heat until MWU temperature setpoint

Operation

86 SCXG-SVX01B-EN

sequence of

operation

Occupied Sequence

All setpoints can be adjusted using the HI

panel. Also, cooling/heating setpoints can

be adjusted in the zone, if using one of the

zone sensor options (BAYSENS020,

BAYSENS021, BAYSENS108,

BAYSENS110, BAYSENS019, or

BAYSENS074). For a complete list of unit

setpoint default values and ranges, see

the

IntelliPak Self-Contained

Programming Guide, PKG-SVP01B-EN

.

Occupied Zone Temperature - Cooling

The unit transitions from unoccupied to

occupied when the occupied/unoccupied

input on the RTM is open for more than

five seconds after having been closed.

This input can be received from Tracer

Summit, the remote NSB zone sensor,

the timed override function, or a field

supplied contact. Dependent on unit

options and the HI programming, the

following sequence will occur:

• The unit will begin MWU and then

switch to the occupied mode after the

MWU setpoint is met.

• Purge will be enabled by Tracer Summit.

Then Tracer Summit will enable the

occupied mode.

• The unit will switch from unoccupied to

occupied control immediately.

Upon entering occupied mode,the IGV

option will close while the supply fan

remains on. The occupied/unoccupied

relay will de-energize.

Zone Temperature Control

(Unit Model Number Digit 9 = 4 or 5)

A zone sensor located directly in the

space sends input to the RTM while the

CV unit is in occupied cooling mode.

When the unit is in occupied cooling, the

RTM controls the zone temperature

within the cooling setpoint deadband by

modulating the economizer option and/or

staging mechanical cooling on and off as

required.

Supply Air Temperature Control

(Unit Model Number Digit 9 = 1, 2, 3, or 6)

When the VAV unit is in occupied cooling,

the RTM controls the supply air

temperature to the specified supply air

cooling setpoint by modulating the

economizer option and/or staging

mechanical cooling on and off as

required. The changeover relay contacts

(field supplied) must be open on units

with hydronic heat for cooling to operate.

Cooling

Upon entering occupied mode, the RTM

receives an input from either the HI, RHI,

Tracer Summit, or the GBAS to start the

supply fan. The RTM supply fan contacts

close and energize the supply fan

contactor. On VAV units with IGV, the fan

delays until the IGV fully close. When the

supply fan starts, the fan proving switch

closes, signaling the RTM that airflow is

established. Depending on unit options,

either the IGV will begin to drive open, the

VFD will ramp the fan, and/or the airside

economizer dampers will open to the

user-defined minimum position.

When a cooling request is sent to the

RTM from the zone sensor, the RTM

evaluates the system operating condi-

tions using the supply air and outdoor

temperature input before sending the

request to the MCM for mechanical

cooling. If outdoor conditions (tempera-

ture and humidity) are suitable or the

EWT is within specified setpoints, the

RTM will attempt to use “free cooling”

without using any compressors. The RTM

will use either the airside or waterside

economizer option. When outdoor air

conditions are not suitable, only mechani-

cal cooling will function and outside air

dampers will remain at their minimum

position. If the unit does not have an

economizer, mechanical cooling will

operate to satisfy cooling requirements.

Units With Economizer

If the entering condenser water

temperature (units with a WSE) or the

outside air enthalpy (units with an ASE) is

appropriate to use “free cooling,” the

economizer will attempt to satisfy the

cooling zone temperature setpoint.

Note: When using an ASE with economizer

enabled, O/A temperature enable can be

used instead of comparative enthalpy if the

O/A temperature falls below the economizer

setpoint.

Then compressors will stage on as

necessary to maintain supply air tem-

perature setpoint, which is user-defined

at the HI. Minimum on/off timing of

compressors prevents rapid cycling.

When both airside and waterside

economizers are on a single unit, priority

must be set at the HI. The economizer

with the highest priority attempts cooling

first. Once it is operating at its maximum,

and if additional cooling is necessary, the

other economizer enables before

mechanical cooling begins.

Cooling/Waterside Economizer

Waterside economizing enables when

the unit’s entering water temperature is

below the unit’s entering mixed air

temperature by 4°F plus the user

adjustable economizer approach

temperature. The approach temperature

default is 4°F.

Waterside economizing disables when

the unit’s entering water temperature is

not below the unit’s entering mixed air

temperature by at least the water

economizer approach temperature

(default value of 4°F). The economizer

acts as the first stage of cooling. If the

economizer is unable to maintain the

zone (CV units) or supply air (VAV units)

temperature setpoint, the compressor

module will bring on compressors as

required to meet the setpoint.

Cooling/Airside Economizer

On units with an airside economizer, a call

for cooling will modulate the fresh air

dampers open. The rate of economizer

modulation is based on deviation of the

zone temperature from setpoint; i.e., the

further away from setpoint, the faster the

fresh air damper will open. The first stage

of cooling will start after the economizer

reaches full open.

Note: The airside economizer will only

function freely if ambient conditions are

below the enthalpy control settings or

below the return air enthalpy if unit has

comparative enthalpy installed. If outside

air is not suitable for “economizing,” the

fresh air dampers drive to the minimum

open position. A field adjustable, factory

default setting at the HI panel or Tracer

Summit can provide the input to establish

the minimum damper position.

When outdoor air conditions are above

the setpoint or comparative enthalpy

control setting, only mechanical cooling

will function and outside air dampers will

remain at their minimum position.

Operation

SCXG-SVX01B-EN 87

sequence of

operation

Mechanical Cooling

If the zone temperature cannot be

maintained within the setpoint deadband

using the economizer option or if there is

no economizer, the RTM sends a cooling

request to the MCM. The compressor

module checks the compressor

protection circuit before closing stage

one. After the first functional stage starts,

the compressor module monitors the

saturated refrigerant temperature and

closes the condenser fan output contact

when the saturated refrigerant

temperature rises above the lower limit

setpoint.

Air-Cooled Units Only

The compressor module closes the

condenser fan output contact when the

saturated refrigerant temperature rises

above the lower limit setpoint.

Water-Cooled Units Only

The WSM modulates the condenser coil

water valves to maintain condenser

temperature, if applicable. Otherwise, it

will check the entering condenser water

temperature to ensure it is greater than

54°F or if not, it will lock out cooling.

Auto Changeover (Units with Heat Only)

When the system mode is in auto, the

mode will change to cooling or heating as

necessary to satisfy the zone cooling

andheating setpoints. The zone cooling

and heating setpoints can be as close as

2°F (1.1°C).

Occupied Zone Temperature - Heating

Relies on input from a sensor directly in

the space, while a system is in occupied

heating mode or an unoccupied period, to

stage electric heat on and off or modulate

the hydronic heating valve as required to

maintain the zone temperature within the

heating setpoint deadband. The supply

fan will operate when there is a request

for heat.

Electric Heat

On units with electric heat, the zone

temperature can be controlled to a

heating setpoint during the occupied

mode by cycling a single stage electric

heater. An interface is provided for field

supplied single stage electric heat. The

zone temperature heating setpoint and

deadband are user defined at the HI

panel.

Hydronic Heat: Hot Water or Steam

On units with hot water or steam heating,

the zone temperature can be controlled

to a heating setpoint during the occupied

mode. The zone temperature heating

setpoint and deadband are user defined

at the HI panel or zone sensor. VAV

occupied heating initiates by closing a

field-supplied switch or relay contacts

connected to the changeover input on the

RTM. Supply air static pressure is

maintained.

Supply Air Setpoint Reset (VAV Units

Only)

Supply air reset can be used to adjust the

supply air temperature setpoint on the

basis of a zone temperature or outdoor

air temperature. Supply air reset

adjustment is available at the HI panel for

supply air heating and supply air cooling

control.

Reset based on outdoor air temperature

Outdoor air cooling reset is sometimes

used in applications where the outdoor

temperature has a large effect on

building load. When the outside air

temperature is low and the building

cooling load is low, the supply air setpoint

can be raised, thereby preventing

subcooling of critical zones. This reset can

lower usage of mechanical cooling, thus

savings in compressor kW, but an

increase in supply fan kW may occur.

Outdoor air heating reset is the inverse of

cooling, with the same principles applied.

For both outdoor air cooling reset and

heating reset, there are three user

defined parameters that are adjustable

through the human interface panel.

• Beginning reset temperature

• Ending reset temperature

• Maximum amount of temperature reset

Reset based on zone temperature

Zone reset is applied to the zone(s) in a

building that tends to overcool or

overheat. The supply air temperature

setpoint is adjusted based on the

temperature of the critical zone(s). This

can have the effect of improving comfort

and/or lowering energy usage. The user-

defined parameters are the same as for

outdoor air reset.

Supply Air Tempering (Hot Water and

Steam VAV Units Only)

When supply air temperature falls below

the supply air temperature deadband low

end, the heating valve modulates open to

maintain the minimum supply air

temperature setpoint.

Daytime Warmup (Units with Supply Air

Temperature Control Only)

During occupied mode, if the zone

temperature falls to a preset, user-

defined zone low limit temperature

setpoint, the unit is put into daytime

warmup. The system changes over to CV

heating, the VAV boxes drive full open.

However, unit airflow modulation control

operates to maintain duct static setpoint,

and full heating capacity is provided until

the daytime warmup setpoint is reached.

The unit is then returned to normal

occupied mode.

Supply Air Tempering

Supply air tempering is available on units

without volume control and with hot

water, steam, or electric heat or units with

supply air temperature control with

steam or electric heat. When the unit is in

heat mode but not actively heating, if the

supply air temperature drops to 10°F

(5.5°C) below the occupied zone heating

temperature setpoint, electric heat will

stage on or the hydronic valve will

modulate to maintain a minimum supply

air temperature. The unit transitions out

of heat mode if the supply air

temperature rises to 10°F (5.5°C) above

the occupied zone heating temperature

setpoint.

Changeover

This mode only functions on units with

supply air temperature control with

hydronic heat. When the changeover

binary input is closed the unit will control

to a discharge air heating setpoint. This

setpoint is entered from the HI, and can

be a higher temperature than the supply

air cooling setpoint. This function

maintains duct static pressure.

Operation

88 SCXG-SVX01B-EN

Compressors

Units use two sizes of hermetic scroll

compressors, 10 and 15 hp, and can use

from two to six compressors. When

viewing the front of the unit, compressors

are identified A through B from left to

right. The second compressor from the

left, or B compressor, is always the first to

come on, unless locked out for a

malfunction or shut off on frost protection.

Refer to Table O-SO-1 for compressor

cycling stages and Table O-SO-3 on page

78 for percent cooling capacity by stage.

The control system logic permits com-

pressor operation only after the supply

fan is on. If the supply fan shuts down,

compressors will not operate. Units

without head pressure control (units with

intermediate piping packages) will lock

out mechanical cooling when the entering

condenser water temperature falls below

54°F. Mechanical cooling will resume

when the entering condenser water

temperature exceeds 58°F.

When there are more than two compres-

sors in an air cooled unit, the first two

sequence of

operation

compressors are manifolded together. If

there are four compressors, the second

two are manifolded.

Compressor Cycling

Compressors cycle to maintain the

operating state required by the

temperature controls. In the event of a

compressor failure, the next available

compressor turns on. Refer to Table O-

SO-1 for compressor cycling by unit

model and tons.

During normal conditions, compressors

will not shut off until they have been on

for at least three minutes and will not turn

on until they have been off for at least

three minutes. Normal operating condi-

tions are established on an individual

compressor basis. When a compressor

starts, its timer also starts. The compres-

sor evaporator circuit frost protection can

override the “minimum” timer and

reduce the five minute minimum re-

quired time period.

When the unit is powered up, or manually

reset there will be a three to eight minute

delay before the first compressor may be

turned on as requested by the unit

temperature control algorithm.

Compressor Lead/Lag Operation

Compressor lead/lag is a user-selectable

feature at the HI panel and is available on

all units. After each request for

compressor operation, the lead

refrigeration circuit or compressor

switches, thereby causing a more

equitable or balanced run time among

compressors.

When lead/lag is enabled, each time the

system cycles, it will alternate between

the standard compressor staging and the

lead/lag staging. Using Table O-SO-1, a

SXWG 30-ton unit will first stage com-

pressor B then A, then AB for first cycle

and A, then AB for the second cycle.

Appropriate condenser valves (water-

cooled and condenser fans (air-cooled)

will stage with appropriate compressors

to maintain saturated condensing

temperature. Enabling lead/lag may drop

a cooling stage when compared to

standard staging. See Table O-SO-1 for

compressor staging.

Operation

Table O-SO-1. Compressor Stages.

Unit Refrigerant Compressor HP Standard Lead/Lag SCM

Size Circuit Type by Stage Compressor Compressor or

Model # Digit 5 A B Staging Staging MCM

SXWG 20, 25 Independent 10 10 B/AB A/AB MCM

SXRG 20

SXWG 30 Independent 15 10 B/A/AB A/AB MCM

SXRG 25

SXWG 35 Independent 15 15 B/AB A/AB MCM

SXRG 32

SCXG-SVX01B-EN 89

Low Ambient Compressor Lockout

This function will lock out the compressor

if the outdoor air temperature sensor

reads an outdoor temperature below the

low ambient compressor lockout

temperature setpoint. This setpoint is

adjustable at the human interface panel.

Compressors will lock out when outdoor

air temperature falls below that selected

temperature and will start again when

the temperature rises 5°F above the

setpoint.

Evaporator Coil Frost Protection

FROSTAT™

The FROSTAT™ system eliminates the

need for hot gas bypass. It utilizes an

evaporator temperature sensor mounted

on the suction line near the TXV bulb of

each circuit to protect the evaporator

from freezing.

If the evaporator temperature ap-

proaches the specified setpoint (adjust-

able between 25 and 35°F at the HI) the

compressor(s) will cycle off. The supply

fan remains on to help de-ice the coil. The

compressors will restart when the

evaporator temperature has risen 10°F

above the specified cutout temperature

and when the compressor(s) have been

off a minimum of three minutes. This

prevents rapid cycling of the compres-

sors.

sequence of

operation

Compressor Safety Devices

The compressors have motor

temperature cutout switches in the motor

windings. These switches are provided

to take the compressors off line during

high motor winding temperature

conditions.

If a compressor low pressure cutout

opens during compressor start-up, the

UCM will not shut the compressor off

during the first two to three minutes after

start-up. This prevents possible nuisance

trips during low ambient start conditions.

See Table O-SO-2.

Each compressor’s discharge line

contains a high pressure cutout. Under

abnormal operating conditions, the cutout

will open to stop compressor operation.

Table O-SO-2. Pressure cutouts

Unit High Pressure Low Pressure

Model Cutout Cutout

SXWF 360/270 20/35

SXRF 405/350 12/27

Step Control

Steps of mechanical cooling are control

based on supply air or zone temperature.

See Table O-SO-1 for compressor

staging.

Capacity is based on an integrating

control concept. The unit capacity

matches the existing load and maintains

an average supply air temperature within

the supply air setpoint temperature

control band region.

The supply air temperature control band

is centered around supply air tempera-

ture setpoint and is adjustable from 2 to

12°F. In a steady state, the unit will either

maintain a constant level of cooling

capacity with the supply air temperature

within the control band, or the highest

active cooling level will cycle to provide

an average supply air temperature equal

to the setpoint.

If the supply air temperature swings

outside the limits of the control band, the

mechanical cooling capacity will increase

or decrease by one level accordingly. The

change occurs by integrating the tem-

perature offset from the control band

limit.

A minimum time delay of five minutes

follows each change in cooling level. This

time delay promotes stability by allowing

the system to respond to the change

before any further control action occurs.

As the supply air temperature ap-

proaches setpoint, the time duration

between changing levels of cooling

capacity increases.

See Figure O-SO-2 for the typical unit

operating curve. Figure O-SO-3 shows

typical unit performance when supply air

temperature swings exceed the control

band limits.

Adjust the supply air temperature control

band according to the desired unit

performance. Increasing the control band

reduces the equipment cycle rate and

increases the maximum potential supply

air temperature deviation from setpoint.

Conversely, decreasing the control band

reduces the maximum potential tem-

perature deviation, but increases the

compressor cycle rate.

Follow these recommendations concern-

ing the supply air temperature control

band settings based on expected unit

sizing:

2 Cooling stage unit: 9°F

3 Cooling stage unit: 7°F

4 Cooling stage unit: 6°F

Operation

90 SCXG-SVX01B-EN

sequence of

operation

Figure O-SO-2. Typical pulldown curve for unit operating properly within control band

Figure O-SO-3. Typical pulldown curve for unit operating improperly outside control band

Service Valve Option

If ordered, service valves are factory

installed on each circuit before and after

the compressor to allow compressor

isolation for servicing.

Operation

SCXG-SVX01B-EN 91

Table M-GI-1. SCWG/SIWG/SCRG/SIRG General Maintenance Data

Water-Cooled Units Air-Cooled Units

Unit Size 2 0 2 5 30 35 20 25 3 2

Compressor Data

Quantity 2 2 1/1 2 2 1/1 2

Nominal Ton/Comp 10 10 10/15 15 10 10/15 15

Circuits 2 2 2 2 2 2 2

Evaporator Coil Data

Rows 2 4 4 4 3 4 4

Sq. Ft. 22.5 25.0 25.0 25.0 25.0 25.0 25.0

FPF 144 144 144 144 144 144 144

Condenser Data

Minium GPM w/o Econ 36 36 46 54 – – –

Minimum GPM w/ Econ 41 41 60 65 – – –

Maximum GPM 80 80 102 119 – – –

Evaporator Fan Data

Quantity 2 2 2 2 2 2 2

Size (Dia. x width - inches) 125/8”x8" 125/8”x9" 125/8”x11" 125/8 x11" 125/8”x8" 125/8”x9" 125/8”x11"

Minimum HP 5 5 5 5 5 5 5

Maximum HP 20 25 25 25 20 25 25

Minimum Design CFM 6350 7250 7250 7250 7250 7250 7250

Maximum Design CFM 8500 10,625 12,750 14,875 8500 10,625 13600

R-22 Refrigerant Data

EER 12.6 13.9 13.4 12.5 10.3 10.7 10.1

IPLV 13.2 14.1 12.9 12.2 11.4 11.4 10.4

Refrigerant Charge - lbs.

Circuit A 25 25 27 27 – – –

Circuit B 25 25 25 27 – – –

Capacity Steps - % 100/53/0 100/53/0 100/65/47/0 100/53/0 100/52/0 100/66/47/0 100/52/0

407C Refrigerant Data

EER 11.6 13.2 12.3 11.3 – – –

IPLV 12.3 13.5 12.2 11.5 – – –

Refrigerant Charge - lbs

Circuit A 23.5 23.5 26.5 26.5

Circuit B 23.5 23.5 23.5 26.5

Capacity Steps - % 100/53/0 100/53/0 100/65/42/6 100/53/0

Filter Data

Quantity 4 4 4 4 4 4 4

Size (inches) (16x25x2) (16x25x2) (16x25x2) (16x25x2) 16x25x2 16x25x2 16x25x2

Quantity 4 4 4 4 4 4 4

Size (inches) 20x25x2 20x25x2 20x25x2 20x25x2 20x25x2 20x25x2 20x25x2

CCRC/CIRC Condenser Match – – – – 20 29 32

Notes:

1. Compressors are Trane 3D® scroll.

2. EER and IPLV are rated in accordance to the ARI Standard 340/360-93 for large unitary equipment. Based on 80/67°F (26.7/19.4°C) to the evaporator coil, nominal airflow and 85-95°F (29.4-

35°C) condenser water.

3. All units operate with R-22. Units ships with full operating charge.

4. Maximum cfm limits are set to prevent moisture carryover on the evaporator coil.

5. Minimum cfm limits are set to ensure stable thermal expansion valve operation at low load conditions.

6. Filter sizes are for units without hot water or steam heating coils

Table M-GI-2. SCWG/SIWG/SCRG/SIRG Self-Contained Heating Coil Maintenance Data

Filter Data for Heating Coil

Quantity 4

Size (inches) 20x18x2

Size (mm) (508x457x51)

Quantity 8

Size (inches) 20x20x2

Size (mm) (508x508x51)

Coil Data Type Rows No. - Size (in) No. - Size (mm) fpf

Steam Coil NS 1 2 - 24 x 58 2 - 609.6x1473.2 42

Hot Water Coil WC 1 2 - 24 x 58 2 - 609.6x1473.2 80

Notes: 1. Hot water and steam heating coils have Prima-Flo® fins and do not have turbulators. 2. For coil capacities, use TOPSS™ (Trane Official

Product Selection Program). 3. Full capacity coils consist of two coils stacked and piped in parallel.

Maintenance

general

information

92 SCXG-SVX01B-EN

Maintenance Procedures

Air Filters

Filter access doors are on the unit’s left

side. Filter access for the 2” filter rack on

optional steam and hot water coils and

airside economizers is also on the left side

Figure M-MP-1. Unit Filter Sizes and Placement for SXWG 20-38 tons or SXRG 20-40 tons

without steam or hot water coil with steam or hot water coil

Note: All filters are 2". These views are from the back of the unit (L-R).

Note: All filters are 2". These views are from the back of the unit (L-R).

18 x 20 18 x 20 18 x 20 18 x 20

20 x 20 20 x 20 20 x 20 20 x 20

18 x 20 18 x 20 18 x 20 18 x 20

16 x 20 16 x 20 16 x 20 16 x 20

20 x 20 20 x 20 20 x 20 20 x 20

18 x 20 18 x 20 18 x 20 18 x 20

of the unit. To replace throwaway filters,

remove the dirty elements and install

new filters with the filter’s directional

arrows pointing toward the fan. Verify

that no air bypasses the filters. See

Figures O-M-1 and O-M-2 for proper filter

placement.

Maintenance

maintenance

procedures





WARNING

Hazardous Voltage w/Capaci-

tors!

Disconnect all electric power, including

remote disconnects before servicing.

Follow proper lockout/tagout proce-

dures to ensure the power cannot be

inadvertently energized. For variable

frequency drives or other energy

storing components provided by Trane

or others, refer to the appropriate

manufacturer’s literature for allowable

waiting periods for discharge of capaci-

tors. Verify with an appropriate voltme-

ter that all capacitors have discharged.

Failure to disconnect power and

discharge capacitors before servicing

could result in death or serious injury.

Note: For additional information

regarding the safe discharge of capaci-

tors, see PROD-SVB06A-EN or PROD-

SVB06A-FR.

is this correct?

SCXG-SVX01B-EN 93

Inspecting and Cleaning the

Drain Pan

Check the condensate drain pan and

drain line to ensure that the condensate

drains properly at least every six months

or as dictated by operating experience.

If evidence of standing water or conden-

sate overflow exists, take steps to identify

and remedy the cause immediately.

Refer to the trouble shooting section of

this manual for possible causes and

solutions.





WARNING

Hazardous Voltage w/Capaci-

tors!

Disconnect all electric power, including

remote disconnects before servicing.

Follow proper lockout/tagout proce-

dures to ensure the power cannot be

inadvertently energized. For variable

frequency drives or other energy storing

components provided by Trane or others,

refer to the appropriate manufacturer’s

literature for allowable waiting periods

for discharge of capacitors. Verify with an

appropriate voltmeter that all capacitors

have discharged. Failure to disconnect

power and discharge capacitors before

servicing could result in death or serious

injury.

Note: For additional information regard-

ing the safe discharge of capacitors, see

PROD-SVB06A-EN or PROD-SVB06A-FR.

Clean drain pans using the following

procedure:

1. Disconnect all electrical power to the

unit.

2. Don the appropriate personal

protective equipment (PPE).

3. Remove all standing water.

4. Use a scraper or other tools to remove

and solid matter. Remove solid matter

with a vacuum device that utilizes high

efficiency particulate arrestance (HEPA)

filters with a minimum efficiency of

99.97% at 0.3 micron particle size.

5. Thoroughly clean the contaminated

area(s) with a mild bleach and water

solution or an EPA-approved sanitizer

specifically designed for HVAC use.

Carefully follow the sanitizer

manufacturer’s instructions regarding

product use.

6. Immediately rinse the drain pan

thoroughly with fresh water to prevent

potential corrosion from the cleaning

solution.

7. Allow the unit to dry thoroughly before

putting the system back into service.

8. Properly dispose of all contaminated

materials and cleaning solution.

Inspecting and Cleaning the

Fan

Inspect the fan section every six months

or more frequently if operating

experience dictates. Clean accumulated

dirt and organic matter on the fan interior

surfaces following the procedure below:

1. Disconnect all electrical power to the

unit.

2. Wear the appropriate personal

protective equipment (PPE).

3. Use a portable vacuum with HEPA

filtration to remove the loose dirt and

organic matter. The filter should be

99.97% efficient at 0.3 micron particle

size.

4. Thoroughly clean the fan and

associated components with an

industrial cleaning solution. Carefully

follow the cleaning solution

manufacturer’s instructions regarding

personal protection and ventilation

when using their product.

5. Rinse the affected surfaces thoroughly

with fresh water and a fresh sponge to

prevent potential corrosion of metal

surfaces.

6. Allow the unit to dry completely before

putting it back into service.

7. Properly dispose of all contaminated

materials and cleaning solution.

Maintenance

maintenance

procedures

94 SCXG-SVX01B-EN

Variable Frequency Drive (VFD)

The VFD access panel is hinged to allow

service access to the fan motor and belt

drive components that are located behind

it. To swing the panel open:

• Remove the unit center cover panel to

the left of the VFD panel.

• Remove and discard the sheet metal

shipping screws along the top and

bottom edges of the VFD panel.

• Disconnect the communications cable

from the keypad on the VFD door panel.

• Turn the two slotted-head fasteners on

the right edge of the VFD panel fully

counterclockwise.

• Pull on the handle to swing the panel

180°.

To close and reattach the panel, reverse

the procedures listed above.

Note: To secure the panel in the open

position during service procedures, attach

the chain mounted to the cabinet frame

behind the unit center cover panel to the

chain retainer notch on the edge of the VFD

panel.

Note: Verify that all wires are in their proper

position and not rubbing before replacing

the panel.

Note: Panel weight rating = 225 lbs. total,

including factory-installed components.

Supply Fan

Fan Drive

Perform the following procedures

according to the “Periodic Maintenance

Check List”.





WARNING

Hazardous Voltage w/Capaci-

tors!

Disconnect all electric power, including

remote disconnects before servicing.

Follow proper lockout/tagout proce-

dures to ensure the power cannot be

inadvertently energized. For variable

frequency drives or other energy storing

components provided by Trane or others,

refer to the appropriate manufacturer’s

literature for allowable waiting periods

for discharge of capacitors. Verify with an

appropriate voltmeter that all capacitors

have discharged. Failure to disconnect

power and discharge capacitors before

servicing could result in death or serious

injury.

Note: For additional information regard-

ing the safe discharge of capacitors, see

PROD-SVB06A-EN or PROD-SVB06A-FR.

1. Rotate the fan wheel to ensure it turns

freely in the proper direction and is not

rubbing on the fan housing, inlet, or inlet

guide vanes. If necessary, center the

fan wheel again.

2. Check the position of both shafts. Fan

and motor shafts should operate

parallel to each other for maximum belt

and bearing life. Shim as necessary

under the motor or fan bearings to

obtain proper alignment.

3. Check the fan motor sheave alignment

with straight edge or a tightly pulled

string. For sheaves of different widths,

place a string in the center groove of

Figure M-MP-4. Fan shaft and motor sheave alignment

each sheave and pull it tight for a center

line. See Figure M-MP-6 for

recommended torques.

4. Once the sheaves are properly aligned,

tighten sheave set screws to proper

torque. See Tables M-MP-1 and M-MP-2

for recommended torques.

5. Check belt tension. Refer to the

“Measuring Belt Tension” section.

6. If required, adjust belt to the minimum

recommended tension. Refer to

“Adjusting Belt Tension” section.

7. Retighten bearing set screws to the

proper torques after aligning the

sheaves. See Tables M-MP-1 and M-

MP-2 for proper torques.

8. Check the fan bearing locking collars

for tightness on the shaft. To tighten the

locking collar, loosen the set screw and

slide the collar into its proper position

over the extended end of the inner

case. Tighten the set screw to the

torque value in Tables M-MP-1 and M-

MP-2.

9. During air balancing, verify the sheave

alignment, belt tension, and that the

shaft is parallel.

Maintenance

maintenance

procedures

SCXG-SVX01B-EN 95

Fan Bearings

The opposite drive end bearing is a

special bearing with close tolerance fit of

balls and races. Replace this bearing with

the same part number as the original

bearing. Follow the fan bearing

lubrication schedules in Tables M-MP-1

and M-MP-2. Use Table M-MP-3 to

reference compatible fan bearing grease

for specific bearings.

Table M-MP-1. Baldor Fan Bearing Lubrication Schedule

Baldor Rated Speed, rpm

Nema/ (IEC) Frame Size 3600 1800 1200 900

up to 210 incl. (132) 5500 hrs 12,000 hrs 18,000 hrs 22,000 hrs

over 210 to 280 incl. (180) 3600 hrs 9500 hrs 15,000 hrs 18,000 hrs

over 360 to 5800 incl. (300) 2200 hrs 3500 hrs 7400 hrs 10,500 hrs

Table M-MP-2. AO Smith Bearing Lubrication Schedule

Speed Frame Standard Service Severe Service Extreme

Service

Over 1800 rpm All 6 mths 3 mths 3 mths

1800 rpm 140-180 3 yrs 1 yr 6 mths

210-280 2 1/2 yrs 10 1/2 mths 5 1/2 mths

320-360 2 yrs 9 mths 4 1/2 mths

400-440 1 1/2 yrs 8 mths 4 mths

Note: Service standard - 8 hrs/day, normal to lgith loading, 100°F ambient temp. max.

Severe service - 24 hrs/day, shock loading, vibration, dirt or dust, 100 to 150°F ambient temp.

Extreme service - heavy shock or vibration, dirt or dust, 100 to 150°F ambient temp.

Table M-MP-3. Compatible Fan Bearing Grease

Motor Vendor Recommended Oil

AO Smith Exxon Polyrex EM

Chevron SRI 2

Dolium R Grease

Chevron Black Perl EP1

Baldor Exxon Polyrex EM

Texaco Polystar

Rykon Premium #2

Pennzoil Pen 2 Lube

Chevron SRI

Maintenance maintenance

procedures

96 SCXG-SVX01B-EN

Table M-MP-4. Fan shaft bearing torques

setscrew hex-size recommended torque

size across flats In-lb ft-lb

1/4"-20 1/8" 180 15

5-16"-18 5-32" 402 33.5

Table M-MP-5. Fan hub and sheave torques

unit fan setscrew torque

size dia. size (ft-lbs)

SCWF 20 16.5" 5/16" 12

SCWF 22

SCWF 25

SCRF 20

SCWF 29 18" 5/16" 12

SCWF 32

SCRF 25

SCRF 30

SCWF 35 20" 5/16" 14

SCWF 38

SCRF 30

SCRF 35

SCWF 42 25" 3/8" 24

SCWF 46

SCWF 52

SCWF 58

SCRF 40

SCRF 50

SCWF 65 27" 3/8" 24

SCWF 72

SCWF 80

SCRF 60

SCWF 90

SCWF C0

SCWF C1

Figure M-MP-6. Fan belt adjustment

Figure M-MP-5. Belt tension gauge

Fan Belt Tension

Note: Check fan belt tension at least twice

during the first days of new belt operation

since there is a rapid decrease in tension

until belts are run-in.

Proper belt tension is necessary to

endure maximum bearing and drive

component life and is based on fan brake

horsepower requirements. If frayed or

worn, replace belts in matched sets.

Measuring Belt Tension

Measure fan belt tension with a

Browning, Gates, or equivalent belt

tension gauge. Determine deflection by

dividing the belt span distance (in inches)

by 64. See Figure M-MP-6. Follow the

procedure below to measure belt tension.

1. Measure belt span between centers of

sheaves and set the large “O” ring of

the tensioning gauge at 1/64 inch for each

inch of belt span.

2. Set the load “O” ring at zero.

3. Place the large end of the gauge at the

center of the belt span. Press down until

the large “O” ring is even with the top

of the belt line or the next belt as in

Figure M-MP-6. Place a straight edge

across the sheaves as a reference

point. See Figure M-MP-4.

4. Remove the gauge. Note that the load

“O” ring now indicates a number on the

plunger scale. This number represents

pounds of force required to deflect the

belt.

5. Check the reading from step 4 against

the values given in Table M-MP-4. If

necessary, readjust belt tension.

deflection = belt span/64

Maintenance maintenance

procedures

SCXG-SVX01B-EN 97

Adjusting Belt Tension

NOTICE

Do not over-tension belts. Exces-

sive belt tension will reduce fan

and motor bearing life, accelerate

belt wear, and possibly cause

shaft failure.

To adjust belt tension refer to Figure M-

MP-6 and perform the following

procedure:

1. Loosen bolts A, B, and E on both sides

of the sliding motor base. See Figure M-

MP-7.

2. Loosen nuts C and D (as required for

motor horsepower) to slide the motor

on its mounting plate in the proper

direction to tension or relieve tension on

the belt.

3. Adjust nuts A-D and bolt E. Do not

stretch the belts over the sheaves.

4. Retighten all nuts and bolts.

5. Verify tension is adjusted properly.

Recommended belt tension range values

are on the unit fan scroll. To access the

fan scroll, face the right-hand side of the

unit and remove the top left panel. The

belt tension label is on the top right-hand

corner of the fan scroll. See Figures O-M-

8 and O-M-9.

The correct operation tension for a V-belt

drive is the lowest tension at which the

belt will not slip under the peak load

conditions. It may be necessary to

increase the tension of some drives to

reduce flopping or excessive startup

squealing.

Figure M-MP-7. Belt tensioning with fan adjustment points

Figure M-MP-8. Location of fan belt label on

fan scroll

Maintenance

maintenance

procedures

Figure O-M-5. Fan assembly.

98 SCXG-SVX01B-EN

• To assist in reducing power generation

emissions, always attempt to improve

equipment performance with improved

maintenance and operations that will

help conserve energy resources.





WARNING

Confined Space Hazards!

Do not work in confined spaces where

sufficient quantities of refrigerant or

other hazardous, toxic, or flammable gas

may be leaking. Refrigerant or other

gases could displace available oxygen to

breathe, causing possible asphyxiation

or other serious health risks. Some

gases may be flammable and or explo-

sive. Evacuate the area immediately and

contact the proper rescue or response

authority. Failure to take appropriate

precautions or to react properly to a

potential hazard could result in death or

serious injury.





WARNING

Hazard of Explosion!

Use only dry nitrogen with a pressure

regulator for pressurizing unit. Do not

use acetylene, oxygen or compressed air

or mixtures containing them for pressure

testing. Do not use mixtures of a

hydrogen containing refrigerant and air

above atmospheric pressure for pres-

sure testing as they may become

flammable and could result in an explo-

sion. Refrigerant, when used as a trace

gas should only be mixed with dry

nitrogen for pressurizing units. Failure to

follow these recommendations could

result in death or serious injury or

equipment or property-only damage.

Refrigerant System

Special Note on Refrigerant Emissions

Follow the Trane recommended

procedures on operation, maintenance,

and service to ensure refrigerant

conservation and emission reduction.

Also, pay specific attention to the

following:

• Whenever removing refrigerant from

air conditioning or refrigerating

equipment, recover for reuse, recycle,

reprocess (reclaim), or properly destroy

it.

• Always determine possible refrigerant

recycling or reclaiming requirements

before beginning recovery. Questions

about recovered refrigerants and

acceptable refrigerant quality

standards are addressed in ARI

Standard 700.

• Use approved containment vessels and

safety standards. Comply with all

applicable transportation standards

when shipping refrigerant containers.

• To minimize emissions while recovering

refrigerant, use recycling equipment.

Always attempt to use methods which

will pull the lowest possible system

vacuum while recovering and

condensing refrigerant into

containment.

• Be aware of any new leak test methods

which eliminate refrigerant as a trace

gas.

• When cleaning system components or

parts, do not use CFC11 (R11) or

CFC113 (R113). Refrigeration system

clean up methods using filters and

dryers are recommended. Do not use

solvents which have ozone depletion

factors. Properly dispose of used

materials.

• Take extra care to properly maintain all

service equipment directly supporting

refrigerant service work such as

gauges, hoses, vacuum pumps, and

recycling equipment.

• Stay aware of unit enhancements,

conversion refrigerants, compatible

parts, and vendor components and

manufacturer’s recommendations that

will reduce refrigerant emissions and

increase equipment operating

efficiencies. Follow specific

manufacturer’s guidelines for

conversion of existing systems.





WARNING

Leak Testing!

Do not exceed 200 psig when leak

testing system. Failure to follow these

instructions could result in an explosion

causing death or serious injury.

In the event of required system repair,

leak test the liquid line, evaporator coil,

and suction line at pressures dictated by

local codes, and using the following

guidelines.

1. Charge enough dry nitrogen into the

system to raise the pressure to 100

psig.

2. Use a halogen leak detector, halide

torch, or soap bubbles to check for leaks.

Check interconnecting piping joints, the

evaporator coil connections, and all

accessory connections.

3. If a leak is detected, release the test

pressure, break the connections and

reassemble it as a new joint, using

proper brazing techniques.

4. If no leak is detected, use nitrogen to

increase the test pressure to 150 psig

and repeat the leak test. Also, use soap

bubbles to check for leaks when

nitrogen is added.

5. Retest the system to make sure new

connections are solid.

6. If a leak is suspected after the system

has been fully charged with refrigerant,

use a halogen leak detector, halide

torch, or soap bubbles to check for leaks.

Refrigerant Evacuation

For field evacuation, use a rotary style

vacuum pump capable of pulling a

vacuum of 400 microns or less.

When connecting the vacuum pump to a

refrigeration system, it is important to

manifold the pump to both the high and

low side of the system. Follow the pump

manufacturer’s directions.

Maintenance

maintenance

procedures

SCXG-SVX01B-EN 99





WARNING

Leak Testing!

Do not exceed 200 psig when leak

testing system. Failure to follow these

instructions could result in an explosion

causing death or serious injury.

In the event of required system repair,

leak test the liquid line, evaporator coil,

and suction line at pressures dictated by

local codes, using the following

guidelines.

1. Charge enough refrigerant and dry

weight. Use an accurate scale or

charging cylinder to determine the

exact weight of the refrigerant entering

the system. Failure to use either a scale

or a charging cylinder can lead to

undercharging or overcharging

resulting in unreliable operation.





WARNING

Hazardous Pressures!

If a heat source is required to raise the

tank pressure during removal of refriger-

ant from cylinders, use only warm water

or heat blankets to raise the tank

temperature. Do not exceed a tempera-

ture of 150°F. Do not under any circum-

stances apply direct flame to any portion

of the cylinder. Failure to follow these

safety precautions could result in a

violent explosion, which could result in

death or serious injury.





CAUTION

Freezing Temperatures!

Do not allow liquid refrigerant to contact

skin. If it does, treat the injury similar to

frostbite. Slowly warm the affected area

with lukewarm water and seek immedi-

ate medical attention. Direct contact

with liquid refrigerant may cause minor

or moderate injury.

refrigerant containers.

• To minimize emissions while recovering

refrigerant, use recycling equipment.

Always attempt to use methods that

will pull the lowest possible system

vacuum while recovering and

condensing refrigerant into

containment.

• Be aware of any new leak test methods

that eliminate refrigerant as a trace gas.

• When cleaning system components or

parts, do not use CFC11 (R11) or CFC

113 (R113). Refrigeration system clean-

up methods using filters and dryers are

recommended. Do not use solvents

which have ozone depletion factors.

Properly dispose of used materials.

• Take extra care to properly maintain all

service equipment directly supporting

refrigerant service work such as

gauges, hoses, vacuum pumps, and

recycling equipment.

• Stay aware of unit enhancements,

conversion refrigerants, compatible

parts, and manufacturer’s

recommendations that will reduce

refrigerant emissions and increase

equipment operating efficiencies.

Follow specific manufacturer’s

guidelines for conversion of existing

systems.

• To assist in reducing power generation

emissions, always attempt to improve

equipment performance with improved

maintenance and operations that will

help conserve energy resources.

Refrigerant Leak Testing

It is important to follow all warnings and

cautions in this section when leak testing

equipment.





WARNING

Use of Pressure Regulator -

Valves - Gauges!

Always use pressure regulators, valves,

and gauges to control drum and line

pressures when pressure testing

equipment. Failure to follow these

instructions could result in an explosion

causing death, serious injury, or equip-

ment damage.

NOTICE

Motor Winding Damage!

Do not use a megohm meter or apply

voltage greater than 50 DVC to a

compressor motor winding while it is

under a deep vacuum. Voltage sparkover

may cause damage to the motor

windings.

Refrigerant Charging

• R22 units

After leak testing and evacuating the

system, charge liquid refrigerant into the

system through the liquid line valve. After

some refrigerant has entered each

circuit, charge gaseous refrigerant into

the suction line shrader valve with the

compressors running.

• R407c

After leak testing and evacuating the

system, charge liquid refrigerant into the

system through the liquid line valve.

NOTICE

Compressor Damage!

Do not operate the compressors without

some refrigerant in each circuit. Failure

to do so may result in compressor

damage.

Special Note on Refrigerant Emissions

Follow the Trane recommended

procedures on operation, maintenance,

and service to endure refrigerant

conservation and emission reduction.

Also, pay specific attention to the

following:

• When removing refrigerant from air

conditioning or refrigerating equipment

recover for reuse, recycling,

reprocessing (reclaim), or properly

destroy it.

• Always determine possible refrigerant

recycling or reclaiming requirements

before beginning recovery. Questions

about recovered refrigerants and

acceptable refrigerant quality

standards are addressed in ARI

Standard 700.

• Use approved containment vessels and

safety standards when shipping

Maintenance

maintenance

procedures

100 SCXG-SVX01B-EN

Figure M-MP-10. Typical water-cooled (SXWF) compressor section components

To charge the system, complete the

following procedure:

1. Charge liquid refrigerant into the liquid

line service valve of each compressor

circuit. The vacuum will draw some of

the required refrigerant into the

system. See Figure O-M-9.

2. Complete the charging process by

charging gaseous refrigerant into the

suction line shrader valve with the unit

running. However, make sure that

some refrigerant is present in each

circuit before starting the compressors.

The refrigerant container should be

upright so that gaseous refrigerant is

drawn off the top.

Note: See Tables M-MP-6 and M-MP-7 for

refrigerant charge requirements.

NOTICE

Compressor Damage!

Do not allow liquid refrigerant to enter

the suction line. Excessive liquid accumu-

lation in the liquid lines may result in

compressor damage.

Maintenance

maintenance

procedures

SCXG-SVX01B-EN 101

Coil Fin Cleaning

Keep coils clean to maintain maximum

performance. For operation at its highest

efficiency, clean the refrigerant coil often

during periods of high cooling demand or

when dirty conditions prevail. Clean the

coil a minimum of once per year to

prevent dirt buildup in the coil fins, where

it may not be visible.

Remove large debris from the coils and

straighten fins before cleaning. Remove

filters before cleaning.

Clean refrigerant coils with cold water

and detergent, or with one of the com-

mercially available chemical coil clean-

ers. Rinse coils thoroughly after cleaning.

Economizer and evaporator coils are

installed so the evaporator is directly

behind the economizer. To clean between

the coils, remove the sheet metal block

off. Access the block off by removing the

corner panels on the unit’s left or right

rear side.

NOTICE

Proper Coil Cleaning Agent!

Do not clean the refrigerant coil with hot

water or steam. The use of hot water or

steam as a refrigerant coil-cleaner agent

may cause high pressure inside the coil

tubing and subsequent damage to the

coil.

Do not use acidic chemical coil cleaners.

Also, do not use alkaline chemical coil

cleaners with a pH value greater then

8.5 (after mixing) without using an

aluminum corrosion inhibitor in the

cleaning solution. Use of the chemical

may result in equipment damage.





WARNING

Hazardous Chemicals!

Coil cleaning agents can be either acidic

or highly alkaline. Handle chemical

carefully. Proper handling should include

goggles or face shield, chemical resistant

gloves, boots, apron or suit as required.

For personal safety refer to the cleaning

agent manufacturer’s Materials Safety

Data Sheet and follow all recommended

safe handling practices. Failure to follow

all safety instructions could result in

death or serious injury.

If the refrigerant coil is installed back to

back with the waterside economizer coil,

use a cleaner that is acceptable for

cleaning both types of coils.





WARNING

Hazardous Voltage w/Capaci-

tors!

Disconnect all electric power, including

remote disconnects before servicing.

Follow proper lockout/tagout proce-

dures to ensure the power cannot be

inadvertently energized. For variable

frequency drives or other energy storing

components provided by Trane or others,

refer to the appropriate manufacturer’s

literature for allowable waiting periods

for discharge of capacitors. Verify with an

appropriate voltmeter that all capacitors

have discharged. Failure to disconnect

power and discharge capacitors before

servicing could result in death or serious

injury.

Note: For additional information regard-

ing the safe discharge of capacitors, see

PROD-SVB06A-EN or PROD-SVB06A-FR.

Inlet Guide Vanes

Perform the following procedure every

six months for proper inlet guide vane

operation:

1. Spray all parts of guide vane assembly

with WD40.

2. Spray all steel parts of guide vane

assembly with ZRC.

3. Spray hubs and moving parts with dry

silicone lubricant (Mobil Mobilux 2, Shell

alvonia 2, or equivalent).

On occasion, the inlet guide vane actuator

or inlet guide vanes may need to be

removed. For proper adjustment of inlet

guide vanes and/or actuator.

Note: Perform this procedure monthly if the

unit is in a coastal area or corrosive

environment.

Maintenance

maintenance

procedures

102 SCXG-SVX01B-EN

Inspecting and Cleaning Coils

Coils become externally fouled as a result

of normal operation. Coil surface dirt

reduces heat transfer ability and can

cause comfort problems, increased

airflow resistance and thus increased

operating energy costs.

Inspect coils at least every six months or

more frequently as dictated by operating

experience. Cleaning frequently is

dependent upon system operating hours,

filter maintenance, efficiency, and dirt

load. Following is the suggested method

for cleaning steam and hot water coils.

Steam and Hot Water Coils

1. Disconnect all electrical power to the

unit.

2. Wear the appropriate personal

protective equipment (PPE).

3. Access both sides of the coil section.

4. Use a soft brush to remove loose

debris from both sides of the coil.

5. Use a steam cleaning machine, starting

from the top of the coil and working

downward. Clean the leaving air side of

the coil first, then the entering air side.

Use a block-off to prevent steam from

blowing through the coil and into a dry

section of the unit.

6. Repeat step 5 as necessary. Confirm

that the drain line is open following

completion of the cleaning process.

7. Allow the unit to dry thoroughly before

putting the system back into service.

8. Straighten any coil fins that may be

damaged with a fin rake.

9. Replace all panels and parts and

restore electrical power to the unit.

10. Ensure that contaminated material

does not contact other areas of the

equipment or building. Properly dispose

of all contaminated materials and

cleaning solutions.

Refrigerant Coils

1. Disconnect all electrical power to the

unit.

2. Wear the appropriate personal

protective equipment (PPE).

3. Access to the coil section of the unit

(both sides).

4. Use a soft brush to remove loose

debris from both sides of the coil.

5. Mix a high quality coil cleaning

detergent with water according to the

manufacturer’s instructions. If the

detergent is strongly alkaline after

mixing (pH 8.5 or higher), it must

contain an inhibitor. Carefully follow the

cleaning solution manufacturer’s

instructions regarding product use.

6. Place the mixed solution in a garden

pump-up sprayer or high pressure

sprayer. If using a high pressure

sprayer note the following:

• Maintain a minimum nozzle spray

angle of 15°

• Spray perpendicular to the coil face

• Protect other areas of the equipment

and internal controls from contact with

moisture or the cleaning solution

• Keep the nozzle at least six inches from

the coil

• Do not exceed 600 psig

Draining the Waterside Economizer Coil

NOTICE

Coil Freezeup!

Properly drain and vent coils when not in

use. Trane recommends glycol protection

in all possible freezing applications. Use a

glycol approved for use with commercial

cooling and heating systems and copper

tube coils. Failure to do so may result in

equipment damage.

Drain plugs are in the piping below each

coil’s supply and return header. Use these

plugs to drain the coil and piping. When

draining the coil, open the vents at the top

of the supply and return headers. Also, a

drain plug is at the bottom of the inlet

condenser manifold and in the outlet pipe

near the unit’s left side. Remove these

plugs to drain the condensers. Be sure to

open the vent plugs at the top of the

condenser inlet and outlet manifold. See

Figure O-M-9.

When refilling the condenser/waterside

economizer coil system with water,

provide adequate water treatment to

prevent the formation of scale or corro-

sion.

Cleaning the Condenser

NOTICE

Proper Water Treatment!

The use of untreated or improperly

treated water in a CenTraVac may result

in scaling, erosion, corrosion, algae or

slime. It is recommended that the

services of a qualified water treatment

specialist be engaged to determine what

water treatment, if any, is required. Trane

assumes no responsibility for equipment

failures which result from untreated or

improperly treated water, or saline or

brackish water.

Condensing water contains minerals that

collect on the condenser tube walls.

Cooling towers also collect dust and

foreign materials that deposit in the

condenser tube. The formation of scale or

sludge in the condenser is indicated by a

decreased water flow, low temperature

difference between inlet and outlet water,

and abnormally high condensing tem-

peratures. To maintain maximum

condenser efficiency, the condenser must

remain free of built-up scale and sludge.

Clean the condenser either mechanically

or chemically.

Mechanical Cleaning of Condenser and

Economizer Coils

1. Turn off the condenser supply water.

Remove drain plugs discussed in the

“Draining the Coil” section on page 91.

2. Remove the condenser head to expose

the condenser tubes.

3. Rotate a round brush through the tubes

to loosen contaminant.

4. Flush tubes with water to push the

sludge out through the drain opening in

the bottom of the supply header and

the return pipe.

5. To clean the economizer tubes, remove

the cast iron header plates at both sides

of the coil between the inlet and outlet

headers (four-row coils only; two-row

coils do not have cover plates at right

end). Rotate round brush through tubes

from left end to loosen contaminants.

Flush tubes with water.

Maintenance

maintenance

procedures

SCXG-SVX01B-EN 103

1. Remove actuator motor from support

plate.

2. Remove shaft coupling.

3. Torque the packing nut to 10-ft.-lbs. of

torque.

4. Replace shaft coupling.

5. Replace actuator motor.

Flow Switch Maintenance

Flow switches have a magnet on the

vane assembly that attracts ferrous

particulate may build up on the magnet to

the point that the vane will wedge and not

operate properly.

When the flow switch does not operate,

remove and replace it or disassemble

and clean it.

Cleaning the Flow Switch

If ferrous particulate contaminates tower

water, the ferrous particles may cling to

the magnet on the switch paddle

assembly. Build up of the ferrous particles

may cause the paddle to stick and not

function properly.

To avoid this problem, remove the switch

and clean each time you clean the

condensers, or clean as needed to keep

the switch operational.

To clean the paddle assembly, remove it

following the procedure below:

1. Remove the switch from the unit.

2. The paddle assembly and wire retainer

clip holds the paddle assembly in the

switch body.

3. Remove the wire retainer clip by

reaching down past the paddle with a

pair of slim nosed pliers and gripping

the end of the wire. Pull up on the wire,

clip, and remove it.

4. After removing the wire clip, use the

pliers to pull the paddle assembly out of

the switch barrel. Clamp the pliers onto

the end of the paddle and remove the

paddle assembly. It will slide straight

out.

5. Clean the ferrous particulate from the

magnet using a rag or tack cloth. The

particulate is attracted to the magnet,

so it is necessary to pull it off. It will not

easily wipe off.

6. After cleaning the magnet, replace the

paddle assembly into the switch body’s

barrel. However, it is important to

position the paddle perpendicular to the

arrow on the switch’s side and place the

paddle’s flat side facing the opposite

direction or the arrow. Push the paddle

assembly in until it hits the barrel cavity

bottom.

7. Place the spring clip into the switch

barrel and push it down with a small,

flat blade screwdriver until the spring

clip engages the groove in the switch

barrel.

8. When replacing the paddle assembly,

check the operation by pushing on the

paddle’s flat side. The paddle should

swing freely in the direction of the

arrow. This action confirms that the

paddle assembly is properly installed.

9. Replace the switch into the unit piping

using a good pipe thread sealer. Tighten

the switch so that its final position has

the arrow parallel to the water pipe and

pointing toward the left end of the unit

(arrow is pointing in the direction of the

water flow).

Maintenance

maintenance

procedures

6. Replace condenser end plates and

clamps. The end plates must be

centered when tightening the clamp.

7. Replace coil headers with gaskets and

torque bolts to 50 ft.-lb.

8. Replace drain and vent plugs.

Chemical Cleaning of Condenser and

Economizer Coil

Chemical cleaning removes scale

deposits built up by minerals in the water.

For a suitable chemical solution, consult a

water treatment specialist. The

condenser water circuit is composed of

copper, steel, and cast iron.

The chemical supply house should

approve or provide all materials used in

the external circulating system, along

with the quantity of cleaning material,

duration of cleaning time, and safety

precautions necessary for handling the

cleaning agent.

Piping Components

Water Valves

Water valves have a stern packing nut. If

there is evidence of water leakage at the

valve stem, proceed as follows:





WARNING

Hazardous Voltage w/Capaci-

tors!

Disconnect all electric power, including

remote disconnects before servicing.

Follow proper lockout/tagout proce-

dures to ensure the power cannot be

inadvertently energized. For variable

frequency drives or other energy storing

components provided by Trane or others,

refer to the appropriate manufacturer’s

literature for allowable waiting periods

for discharge of capacitors. Verify with an

appropriate voltmeter that all capacitors

have discharged. Failure to disconnect

power and discharge capacitors before

servicing could result in death or serious

injury.

Note: For additional information regard-

ing the safe discharge of capacitors, see

PROD-SVB06A-EN or PROD-SVB06A-FR.

104 SCXG-SVX01B-EN

Maintenance Periodic

Checklists

Monthly Checklist

The following check list provides the

recommended maintenance schedule to

keep the commercial self-contained

equipment running efficiently.





WARNING

Hazardous Voltage w/Capaci-

tors!

Disconnect all electric power, including

remote disconnects before servicing.

Follow proper lockout/tagout proce-

dures to ensure the power cannot be

inadvertently energized. For variable

frequency drives or other energy storing

components provided by Trane or others,

refer to the appropriate manufacturer’s

literature for allowable waiting periods

for discharge of capacitors. Verify with an

appropriate voltmeter that all capacitors

have discharged. Failure to disconnect

power and discharge capacitors before

servicing could result in death or serious

injury.

Note: For additional information regard-

ing the safe discharge of capacitors, see

PROD-SVB06A-EN or PROD-SVB06A-FR.

1. Inspect unit air filters. Clean or replace

if airflow is blocked or if filters are dirty.

2. Inspect coils for excess moisture or

icing. Icing on the coils may indicate low

airflow supply, restricted airflow from

dirty fins, evaporator frost protection

sensor problems, or a shortage of

refrigerant flowing through the coil.

3. Check that condensate from the

evaporator and economizer coils flows

freely through the condensate piping,

traps, drain pan, and drainage holes.

Remove algae and or any airflow

obstructions.

4. Check the condition and tension of fan

belts. Adjust tension if belts are floppy

or squeal continually. Replace worn or

fraying belts in matched sets.

Note: Check belt tension and adjust it at

least twice daily the first days of new belt

operation. Belt tension will rapidly decrease

until the belts are run in.

5. Check the liquid line sight glasses

during operation. Bubbles in the sight

glasses indicate a possible shortage of

refrigerant or an obstruction in the

liquid lines, e.g. dirty liquid line filter

driers.

6. Inspect filter driers for leaks, flow

obstructions, or temperature drop

across the filter drier. A noticeable

temperature differential, e.g. 5°F, in the

liquid line may indicate an obstruction.

Replace the filter drier if it appears

clogged.

7. Inspect the optional waterside

economizer coil. Clean the coil to

prevent airflow restrictions through the

fins.

8. Check and record operating pressures.

Semi-Annual Maintenance

1. Verify the fan motor is properly

lubricated. Follow lubrication

recommendations on the motor tag or

nameplate. Contact the motor

manufacturer for more information.

2. Lubricate fan bearings. For best results,

lubricate bearings during unit operation.

Refer to the “Fan Bearings” section on

page 84.

3. With power disconnected, manually

rotate the fan wheel to check for

obstructions in the housing or

interference with fan blades or inlet

guide vane option. Remove

obstructions and debris. Center the fan

wheel if necessary.

4. Check the fan assembly sheave

alignment. Tighten set screws to their

proper torques.

5. Check water valves for leakage at

valve stem packing nut.

6. Inspect the inlet vane assembly and

perform maintenance procedures in

the IGV maintenance section.

Note: Perform this procedure monthly if the

unit is in a coastal or corrosive environ-

ment.

Annual Maintenance

Check and tighten all set screws, bolts,

locking collars and sheaves.

1. Inspect, clean, and tighten all electrical

connections.

2. Visually inspect the entire unit casing

for chips or corrosion. Remove rust or

corrosion and repaint surfaces.

3. Visually check for leaks in refrigerant

piping.

4. Inspect fan, motor, and control contacts.

Replace badly worn or eroded contacts.

5. Inspect the thermal expansion valve

sensing bulbs for cleanliness, good

contact with the suction line, and

adequate insulation from ambient air.

6. Verify the superheat setting is 12 -17°F

at the compressor.

When checking operating pressures and

conditions, establish the following

nominal conditions for consistent mea-

surements.

1. Leaving air temperature greater than

60°F

2. Entering air temperature is 80 - 90°F

3. Entering water temperature greater

than 65°F

4. Inlet guide vanes at least halfway open

5. Compressors running at full load

6. Drain the condensing water system

and inspect it thoroughly for fouling,

clean condensers if necessary.

Maintenance

maintenance

procedures

SCXG-SVX01B-EN 105

System Checks





WARNING

Live Electrical Components!

During installation, testing, servicing and

troubleshooting of this product, it may be

necessary to work with live electrical

components. Have a qualified licensed

electrician or other individual who has

been properly trained in handling live

electrical components perform these

tasks. Failure to follow all electrical

safety precautions when exposed to live

electrical components could result in

death or serious injury.

Before proceeding with technical trouble

charts or controls checkout, complete the

following system analysis:

1. Measure actual supply voltage at the

compressor and an motor terminals

with the unit running. Voltage must be

within the range listed on the motor

nameplate. Phase imbalance must be

less than 2.0%.

2. Check all wiring and connections to be

sure that they are intact, secure and

properly routed. The as wired system

diagrams are provided in the unit

control panel.

3. Check that all fuses are installed and

properly sized.

4. Inspect air filters and coils to bel sure

that airflow to the unit is not restricted.

5. Check the zone thermostat settings.

6. Ensure that the fan is rotating in the

proper direction. If phasing is wrong at

the main power terminal block, the fan

and compressors will not run correctly.

7. Inspect ductwork and duct connections

for tightness.

Operating Procedures

Install pressure gauges on the discharge

and suction line access valves. When the

unit has stabilized (after operating

approximately 15 minutes at full load),

record suction and discharge pressures.

System malfunctions such as low airflow,

line restrictions, incorrect refrigerant

charge, malfunctioning of expansion

valves, damaged compressors, etc. will

result in pressure variations which are

outside the normal range.

Note: If phasing at the main incoming

power terminal is incorrect, switch two of

the three incoming power leads. If a

compressor has been replaced and the

phase is changed at the compressor, it will

run backwards and discharge pressure will

be very low. To resolve incorrect compres-

sor wire phasing, change phasing at the

compressor.

It is important that pressures be mea-

sured under stable and constant condi-

tions in order for the readings to be

useful.

Voltage Imbalance

Voltage imbalance on three-phase

systems can cause motor overheating

and premature failure. Maximum

allowable imbalance is 2.0%, and the

readings used to determine it must be

measured at the compressor terminals.

Voltage imbalance is defined as 100

times the sum of the division of the three

voltages from the average voltage. If, for

example, the three measured voltages

are 221, 230, 227, the average is:

(221+230+227) = 226 volts

3

Therefore, the percentage of voltage

imbalance is:

100*(226-221) = 2.2%

226

In this example, 2.2% imbalance of more

than 2.0% exists, be sure to check the

voltage at the unit disconnect and

terminal block switch. If an imbalance at

the unit disconnect switch does not

exceed 2.0%, the imbalance is caused by

faulty wiring within the unit. Be sure to

conduct a thorough inspection of the unit

electrical wiring connections to locate the

fault, and make any repairs necessary.

troubleshootingMaintenance

Common Unit Problems and Solutions

Problem Possible Cause Remedy

Drain pan is overflowing Plugged drain line Clean drain line

Unit not level Level unit

Standing water in drain pan Unit not level Level Unit

Plugged drain line Clean drain line

Wet interior insulation Coil face velocity too high Reduce fan speed

Improper trap design Design trap per unit installation instructions

Drain pan leaks/overflowing Repair Leaks

Condensation on surfaces Insulate surfaces

Excess dirt in unit Missing filters Replace filters

Filter bypass Reduce filter bypass

Microbial growth (mold) Standing water in drain pan See “Standing water in drain pan” above

Moisture problems See “Wet interior insulation” above

106 SCXG-SVX01B-EN

Diagnostics

Refer to the

IntelliPak Self-Contained

Programming Guide, PKG-SVP01B-EN,

for specific unit programming and

troubleshooting information. In particular,

reference the “Service Mode Menu” and

“Diagnostic Menu”sections in the

programming guide. Refer to the

following text for general diagnostic and

troubleshooting procedures. Common

diagnostics and troubleshooting

procedures follow below.

A

Auto Reset S/A Static Pressure Limit

Problem: The supply air static pressure

went too high.

Reason for Diagnostic: The S/A static

pressure exceeded the S/A static

pressure limit setpoint for at least one

second continuously.

UCM Reaction: A "supply air pressure

shutdown" signal is sent to the following

functions:

a. Compressor staging control,

b. Economizer actuator control,

c. Heat operation,

d. Supply fan control,

e. IGV/VFD control,

f. Exhaust fan control,

g. Exhaust actuator control

Reset Required: (PAR) An automatic reset

occurs after the IGV close. The supply fan

is not allowed to restart for 15 seconds

after the diagnostic occurs. An auto reset

will also occur if the unit cycles out of

occupied mode and back.

C

CO2 Sensor Failure

Problem: The VCM CO2 sensor input

signal is out of range.

Check: Check field/unit wiring between

sensor and VCM.

Reason for Diagnostic: The unit is reading

a signal that is out of range for the CO2

sensor transducer input.

UCM Reaction: The CO2 reset function

disables.

Reset Required: (PAR) An automatic reset

occurs after the CO2 sensor transducer

input receives a signal that is within range

for ten continuous seconds.

Compressor Contactor Fail - Circuit 1, 2,

3, or 4

Problem: The compressor contactor for

Ckt. 1, 2, 3, or 4 has malfunctioned.

Reason for Diagnostic: The circuit

compressor proving input is detected

closed continuously for more than three

seconds while neither compressor output

on that circuit closes.

UCM Reaction: A "lockout ckt #1, 2, 3, or 4

request is issued to the compressor

staging control function.

Reset Required: (PMR) A manual reset is

required after the disgnostic is set. It can

be reset by the HI or Tracer Summit.

Compressor Trip - Ckt 1, 2, 3, or 4

Problem: The compressor ckt #1, 2, 3, or 4

has tripped.

Reason for Diagnostic: The ckt #1, 2, 3, or

4 compressor proving input is detected

open continuously for more than 3

seconds when either or both compressor

outputs on that circuit energize (as

described in the compressor protection

function).

Reason for Diagnostic: The circuit

compressor proving input is detected

open continuously for more than 3

seconds when either or both compressor

outputs on that circuit energize (as

described in the compressor protection

function).

UCM’ Reaction: A “lockout ckt #1, 2, 3, or

4” request is issued to the compressor

staging control function.

Reset Required: (PMR) A manual reset is

required after this diagnostic occurs. The

diagnostic can be reset by the unit

mounted HI module or Tracer Summit.

Condenser Temp Sensor Failure - Circuit 1,

2, 3, or 4

Problem: The saturated condenser

temperature input is out of range for circuit

#1, 2, 3, or 4.

Check: Sensor resistance should be

between 830 ohms (200°F) and 345.7

ohms (-40°F). If so, check field/unit wiring

between sensor and MCM/SCM.

Reason for Diagnostic: The unit is reading a

signal that is out of range for the circuit #1,

2, 3, or 4 saturated condenser temperature

sensor. (temp < -55°F or temp > 209°F).

UCM Reaction: A “Lockout Ckt # 1, 2, 3, or

4” request is issued to the compressor

staging control function.

Reset Required: (PAR) An automatic reset

occurs after the circuit 1, 2, 3, or 4

condenser temp input returns to its

allowable range within 10 seconds.

D

Dirty Filter

Problem: There is a dirty filter.

Reason for Diagnostic: The filter switch

input on the RTM is closed for more than

60 seconds continuously.

UCM Reaction: An information only

diagnostic is set.

Reset Required: (INFO) An automatic reset

occurs after the dirty filter input reopens

for 60 continuous seconds.

E

ECEM Communications Failure

Problem: The RTM has lost communication

with the ECEM.

Check: Field/unit wiring between RTM and

ECEM module.

Reason for Diagnostic: The RTM has lost

communication with the ECEM.

UCM Reaction: If the unit has the

comparative enthalpy option, the

economizer enable r.e. enthalpy function

will revert to level 2 enthalpy comparison.

diagnostics

Maintenance

SCXG-SVX01B-EN 107

Reset Required: (PAR) An automatic reset

occurs after communication has been

restored.

Emergency Stop

Problem: The emergency top input is

open.

Reason for Diagnostic: An open circuit

has occurred on the emergency stop

input caused either by a high duct temp t-

stat trip, or the opening of field-provided

contacts, switch, etc.

UCM Reaction: Off or close requests are

issued as appropriate to the following

functions;

a. Compressor staging/chilled water

cooling control

b. Heat operation

c. Supply fan control and proof of

operation

d. Exhaust fan control and proof of

operation.

e. Exhaust actuator control

f. Outside air damper control

g. On VAV units, IGV/VFD control

Reset Required: (PMR) A manual reset is

required after the emergency stop input

recloses. The diagnostic can be reset by

the HI.

Entering Cond Water Temp Sensor Fail

Problem:

Activation Conditions: temperature < -

50°F or temperature > 209°F, and unit

configured for water cooled

condenser

c. Time to React: 10 sec < T < 20 sec

d. Diagnostic Text (Human Interface

Display) “ENT COND WATER TEMP

SENSOR FAIL”

e. Actions to be Initiated: A “Lockout All

Ckts ” request is issued to the

“Compressor Staging Function”

f. Reset: An automatic reset occurs after

the entering condenser water

temperature input returns to within range

continuously for 15 seconds.

Entering Water Temp Sensor Fail

a. Data used (module, packet, byte, bit):

WSM, 01,18,05

b. Activation Conditions: temperature < -

50°F or temperature > 209°F, and unit

configured with water cooled

condenser and/or economizer

c. Time to React: 10 sec < T < 20 sec

d. Diagnostic Text (Human Interface

Display) “ENTERING WATER TEMP

SENSOR FAIL”

e. Actions to be Initiated: A “Disable

Water Side Economizer” request is

issued to “Water Side Economizer

Temperature Enable Function”

f. Reset: An automatic reset occurs after

the Entering Water Temp. input returns to

within range continuously for 10 seconds.

Evap Temp Sensor Failure - Circuit 1, 2, 3,

or 4

Problem: The evaporator temperature

sensor (ckt #1, 2, 3, or 4) is out of range.

Check: Sensor resistance should be

between 830 ohms (200°F) and

345.7Kohms (-40°F). If so, check field/unit

wiring between sensor and MCM/SCM.

Reason for Diagnostic: The unit is reading

a signal that is out of range for the circuit

#1 evaporator temperature sensor input

(temp < -55°F or temp > 209°F).

UCM Reaction: The coil frost protection

function for the refrigeration circuit (#1, 2,

3, or 4) only is disabled.

Reset Required: (PAR) An automatic reset

occurs after the #1, 2, 3, or 4 evap temp

input returns to its allowable range for 10

seconds.

G

GBAS 0-5 VDC Module Comm Failure

Problem: The RTM has lost

communication with the GBAS module.

Check: Field/unit wiring between RTM

and GBAS.

Reason for Diagnostic: The RTM has lost

communication with the GBAS module.

UCM Reaction: The UCM will initiate the

following actions;

a. If the demand limit input was closed

prior to the communications loss, then

the demand limit commands issued to

the heat operation function (if

applicable) and the compressor staging/

chilled water cooling function will be

cancelled.

b. If any of the GBAS setpoint control

parameters are the HI-selected setpoint

sources, then those setpoints will revert

to the default HI setpoints.

c. Any active GBAS output control

parameters will be ignored.

d. A failsafe function in the GBAS module

will cause all GBAS outputs to be

zeroed and deenergized.

Reset Required: (PAR) An automatic reset

occurs after communication has been

restored.

H

Heat Failure

Problem: The heat has failed.

(Electric heat unit) Typically, this is

because the electric heat section became

too hot.

Reason for Diagnostic: The heat fail input

on the heat module was closed:

a. for more than 80 seconds,

b. for ten consecutive occurrances (each

lasting five seconds or more) within a

210 second period.

UCM Reaction: An information only

diagnostic is set.

Reset Required: (INFO) An automatic

reset occurs after the heat fail input

remains open for 210 seconds

continuously.

Heat Module Auxilliary Temperature

Sensor Fail

Problem: The heat mod aux temp sensor

input is out of range.

Check: Sensor resistance should be

between 830 ohms (200°F) and 345.7

ohms (-40°F). If so, check field/unit wiring

between sensor and heat module.

Reason for Diagnostic: At least one

enabled unit function has the heat

module auxillary temperature input

designated as its sensor, and the unit is

reading a signal that is out of range for

this input (temp < -55°F or temp > 209°F).

UCM Reaction: The functions that

diagnosticsMaintenance

108 SCXG-SVX01B-EN

designated the heat module auxillary

temperature input as their input are

disabled.

Reset Required: (PAR) An automatic reset

occurs after the heat module auxillary

temperature input returns to its allowable

range for 10 seconds.

Heat Module Comm Failure

Problem: The RTM has lost

communication with the heat module.

Check: Check field/unit wiring between

RTM and heat module.

Reason for Diagnostic: The RTM has lost

communication with the heat module.

UCM Reaction: An “all heat off” request

is sent to the heat operation function.

If the unit has staged gas or electric heat,

all heat module outputs will be zeroed

and deenergized.

If the unit has hydronic heat or chilled

water installed, the unit will turn off the

supply fan and close the outside air

damper upon the occurrance of a heat

module comm failure. A failsafe function

in the heat module will cause all water

valves to be set to 100% to provide full

water flow. Unless used for switching

purposes (air handlers with chilled water

and mod gas, or chilled water and

hydronic heat) all binary outputs will be

deenergized.

Reset Required: (PAR) An automatic reset

occurs after communication has been

restored.

L

Low Air Temp Limit Trip

Problem: The low air temp limit has

tripped. (Units with steam or hot water

heating, or air handlers with chilled water

cooling)

Reason for Diagnostic: A low air temp

limit trip is detected continuously for

more than one second. This can occur if

the hydronic heat low air temp limit input

closes for > 1 second, or if the chilled

water low air temp limit trip input opens

for > 1 second. On units with both

hydronic heat and chilled water, both low

air temp limit inputs are active, and the

unit will respond in the same manner

regardless of which input is used.

UCM Reaction: The UCM will initiate the

following actions;

a. An “open all water valves”request is

issued to the heat module function,

causing any steam, hot water, or chilled

water valves on the unit to open.

b. An “all heat off” request is issued to

the heat control function.

c. A “fan off” request is sent to the supply

fan control function.

d. A “close damper” request is sent to

the economizer actuator control

function.

Reset Required: (PMR) A manual reset is

required after the low air temp limit trip

condition clears. The diagnostic can be

reset at the unit mounted human

interface, by Tracer Summit, or by cycling

power to the RTM.

Low Pressure Control Open - Circuit 1, 2,

3, or 4

Problem: The Low Pressure Control (LPC)

for Ckt #1, 2, 3, or 4 is open.

Check: State of refrigerant charge for ckt

#1, 2, 3, or 4.

Reason for Diagnostic: The Ckt # 1 LPC

input is detected open as described in the

compressor protection function.

UCM Reaction: A “Lockout Ckt # 1, 2, 3, or

4” request is issued to the compressor

staging control function.

Reset Required: (PMR) A manual reset is

required anytime after the diagnostic is

set. The diagnostic can be reset by the

human interface, Tracer Summit, or by

cycling power to the RTM.

M

Manual Reset SA Static Press Limit

Problem: The supply air static pressure

went too high for the third consecutive

time.

Reason for Diagnostic: The auto reset

supply air static pressure limit diagnostic

has occurred for the third time while the

unit is operating in occupied mode.

UCM Reaction: A "supply air pressure

shutdown" signal is sent to the following

functions;

a. Compressor staging control,

b. Economizer actuator control,

c. Heat operation,

d. Supply fan control,

e. IGV/VFD control,

f. Exhaust fan control

g. Exhaust actuator control

Reset Required: (PMR) A manual reset is

required and can be accomplished at the

HI, Tracer Summit, or by cycling power to

the RTM.

MCM Communications Failure

Problem: The RTM has lost communication

with the MCM.

Check: Check field/unit wiring between

RTM and MCM.

Reason for Diagnostic: The RTM has lost

communications with the MCM.

UCM Reaction: A “Lockout” request is

sent to the compressor staging control

function. And a failsafe function in the

MCM will cause all MCM outputs to be

zeroed and deenergized.

Reset Required: (PAR) An automatic reset

occurs after communication has been

restored.

Mode Input Failure

Problem: The RTM mode input is out of

range.

Check: Sensor resistance should be

between 1 ohm and 40 ohms. If so, check

field/unit wiring between sensor and RTM.

Reason for Diagnostic: The mode input

signal on the RTM is out of range

(resistance < 1 ohm or resistance > 40

ohms).

UCM Reaction: The system mode reverts

to the default (HI set) system mode.

Reset Required: (INFO) An automatic reset

diagnosticsMaintenance

SCXG-SVX01B-EN 109

occurs after the mode input returns to its

allowable range for 10 seconds.

N

NSB Panel Zone Temperature Sensor

Failure

Problem: The NSB panel's zone temp

sensor input is out of range. (This input is

at the NSB panel, not on the unit itself).

Check: If have an external sensor

connected to the NSB panel zone sensor

input, then the internal NSB panel zone

sensor should be disabled. Verify sensor

resistance. If in valid range, check wiring

between the sensor and NSB panel.

NSB Panel Comm Failure

Problem: The RTM has lost

communications with the night setback

panel (programmable zone sensor).

Check: Field/unit wiring between RTM

and NSB Panel.

Reason for Diagnostic: The RTM has lost

communication with the NSB panel.

UCM Reaction: The unit reverts to the

next lower priority mode switching

source (typically the HI default mode). If

the NSB panel zone sensor is the

designated sensor source for any

functions, those functions are disabled.

Reset Required: (PAR) An automatic reset

occurs after communication has been

restored.

O

O/A Humidity Sensor Failure

Problem: The outside air humidity sensor

data is out of range.

Check: Check field/unit wiring between

the sensor and RTM.

Reason for Diagnostic: The unit is reading

a signal that is out of range for the outside

air humidity sensor (humidity < 5% or

humidity > 100%).

UCM Reaction: The economizer enable

enthalpy function reverts to dry-bulb

temperature changeover (“Level 1”)

control.

Reset Required: (PAR) An automatic reset

occurs after the OA humidity input

returns to its allowable range for 10

seconds.

O/A Temp. Sensor Failure

Problem: The outside air temperature

sensor input is out of range.

Check: Sensor resistance should be

between 830 ohms (200°F) and 345.7

ohms (-40°F). If so, check field/unit wiring

between sensor and RTM.

Reason for Diagnostic: The unit is reading

a signal that is out of range for the outside

air temperature input on the RTM (temp.

< -55°F or temp > 209°F).

UCM Reaction: These unit functions

occur:

• low ambient compressor lockout

disables

• O/A damper drives to minimum position

• on VAV units with S/A temp. reset type

selected as O/A temp. reset, the reset

type reverts to “none” for the duration

of the failure

Reset Required: (PAR) an automatic reset

occurs after the O/A temperature input

returns to its allowable range. To prevent

rapid cycling of the diagnostic, there is a

10 second delay before the automatic

reset.

Occupied Zone Heat Setpoint Failure

Problem: The occupied zone heat setpoint

input is out of range.

Reason for Diagnostic: The input

designated as occupied zone heating

setpoint source is out of range for the

outside air temperature input on the RTM

(temp. < 45°F or temp > 94°F).

UCM Reaction: The active occupied zone

heating setpoint reverts to the default

value.

Reset Required: (PAR) an automatic reset

occurs after the occupied zone heating

setpoint input returns to its allowable

range for 10 continuous seconds, or after

a different occupied zone heating setpoint

selection source is user-defined.

R

Return Air Humidity Sensor Failure

Problem: On units with both airside

economizer and comparative enthalpy

installed, the return air humidity sensor

input is out of range.

Check: Check field/unit wiring between

the sensor and ECEM.

Reason for Diagnostic: The unit is reading

a signal that is out of range for the return

air humidity sensor (humidity < 5% or

humidity > 100%).

UCM Reaction: The economizer enable

r.e. enthalpy function reverts to reference

enthalpy changeover (“Level 2”) control.

Reset Required: (PMR) An automatic

reset occurs after the RA humidity input

returns to its allowable range

continuously for 10 seconds.

Return Air Temp Sensor Failure

Problem: On units with the comparative

enthalpy option, the return air

temperature sensor input is out of range.

Check: Sensor resistance should be

between 830 ohms (200°F) and 345.7

ohms (-40°F). If so, check field/unit wiring

between the sensor and ECEM.

Reason for Diagnostic: The unit is reading

a signal that is out of range for the return

air humidity sensor (temp < -55°F or

temp > 209°F).

UCM Reaction: The economizer enable

r.e. enthalpy function reverts to reference

enthalpy changeover (“Level 2”) control.

Reset Required: (PAR) An automatic reset

occurs after the RA temp input returns to

its allowable range continuously for 10

seconds.

diagnosticsMaintenance

110 SCXG-SVX01B-EN

RTM Aux. Temp. Sensor Failure

Problem: The RTM auxillary temperature

sensor data is out of range.

Check: Sensor resistance should be

between 830 ohms (200°F)and 345.7

ohms (-40°F). If so, check field/unit wiring

between sensor and RTM.

Reason for Diagnostic: At least one

enabled unit function has the RTM

auxillary temperature input designated

as its sensor, and the unit is reading a

signal that is out of range for this input

(temp. < -55°F or temp > 209°F).

UCM Reaction: The functions with the

RTM auxillliary temperataure input

deignated as their sensor are disabled.

Reset Required: (PAR) an automatic reset

occurs after the designated zone

temperature signal returns to its

allowable range. To prevent rapid cycling

of the diagnostic, there is a 10 second

delay before the automatic reset.

RTM Data Storage Error

Problem: There was a data transmission

error.

Check: This can be caused by an

intermittant power loss. Turn the unit off

for 1-2 minutes, then back on again. If

diagnostic persists, then the RTM may

need to be replaced.

Reason for Diagnostic: An error occurred

while the RTM was writing data to its

internal non-volitile memory (EEPROM).

UCM Reaction: An information only

diagnostic will be displayed at the human

interface.

Reset Required: (INFO) A manual reset

may be made at the human interface, at

Tracer Summit, or by cycling power to

the RTM.

RTM Zone Sensor Failure

Problem: The RTM zone temperature

sensor input is out of range.

Check: Sensor resistance should be

between 830 ohms (200°F) and 345.7

ohms (-40°F). If so, check field/unit wiring

between sensor and RTM.

Reason for Diagnostic: At least one

enabled unit function has the RTM zone

temperature input designated as its

sensor, and the unit is reading a signal

that is out of range for this input (temp. < -

55°F or temp > 150°F).

UCM Reaction: The functions with the

RTM zone temperataure input deignated

as their sensor are disabled.

Reset Required: (PAR) an automatic reset

occurs after the designated zone

temperature signal returns to its

allowable range. To prevent rapid cycling

of the diagnostic, there is a 10 second

delay before the automatic reset.

S

SCM Communication Failure

Problem: The RTM has lost

communication with the SCM.

Check: Check field/unit wiring between

the RTM and SCM.

Reason for Diagnostic: The RTM has lost

communication with the SCM.

UCM Reaction: A “lockout” request is

sent to the compressor staging control

function. A failsafe function in the SCM

will cause all SCM outputs to be zeroed

and deenergized.

Reset Required: (PAR) An automatic reset

occurs after communication has been

restored.

Space Static Press Setpt Failure

Problem: The active space static pressure

setpoint is out of range.

Check: Check setpoint value. Also, if

space pressure setpoint source is GBAS,

but this setpoint has not been assigned to

any of the four analog inputs on GBAS,

this message will occur.

Reason for Diagnostic: The unit is reading

a signal that is out of range for the space

static pressure setpoint (input < 0.03 iwc

or input > 0.20 iwc).

UCM Reaction: The default space

pressure setpoint will become the active

space pressure setpoint.

Reset Required: (PAR) An automatic reset

occurs after the designated space

pressure setpoint source sends a signal

within range for 10 continuous seconds,

or after a different space pressure

setpoint source is user-defined.

Supply Air Pressure Sensor Failure

Problem: The supply air pressure sensor

voltage input is out of range.

Check: Check field/unit wiring between

the sensor and RTM.

Reason for Diagnostic: The unit is reading

a signal that is out of range for the supply

air pressure sensor voltage input (input <

40mV or input > 4.75V)

UCM Reaction: The IGVs will drive closed,

and the following functions are disabled;

a. SA pressure control

b. SA static pressure limit

Reset Required: (PAR) An automatic reset

occurs after the SA temp heating setpoint

input returns to within range for 10

continuous seconds, or after a different

SA temp heating setopint selection

source is user-defined.

Supply Air Pressure Setpoint Failure

Problem: The SA pressure input signal is

out of range.

Reason for Diagnostic: The SA pressure

setpoint input is sending a signal that is

out of range (Input < 1.0 iwc or input > 4.3

iwc)

UCM Reaction: The default SA pressure

setpoint will become the active SA

pressure setpoint.

Reset Required: (PAR) An automatic reset

occurs after the designated SA pressure

setpoint source sends a signal within

range for 10 continuous seconds, or after

a different SA pressure setpoint source is

user-defined.

diagnosticsMaintenance

SCXG-SVX01B-EN 111

Supply Air Temp Cool Setpoint Fail

Problem: The active supply air

temperature cooling setpoint is out of

range.

Reason for Diagnostic: The input

designated as the SA temp cooling

setpoint is out is out of range (temp <

35°F or temp > 95°F).

UCM Reaction: The default HI-set SA

temp cooling setpoint becomes the active

SA temp cooling setpoint.

Reset Required: (PAR) An automatic reset

occurs after the SA temp cooling setpoint

input returns to within range for 10

continuous seconds, or after a different

SA temp cooling setopint selection

source is user-defined.

Supply Air Temp Heat Setpoint Fail

Problem: The active supply air

temperature cooling setpoint is out of

range.

Reason for Diagnostic: The input

designated as the SA temp heating

setpoint is out is out of range (temp <

35°F or temp > 185°F).

UCM Reaction: The default HI-set SA

temp heating setpoint becomes the

active SA temp heating setpoint.

Reset Required: (PAR) An automatic reset

occurs after the SA temp heating setpoint

input returns to within range for 10

continuous seconds, or after a different

SA temp heating setopint selection

source is user-defined.

Supply Air Temperature Failure

Problem: The supply air temperature

sensor input is out of range.

Check: Sensor resistance should be

between 830 ohms (200°F) and 345.7

ohms (-40°F). If so, check field/unit wiring

between sensor and RTM.

Reason for Diagnostic: The unit is reading

a signal that is out of range for the supply

air temperature input on the RTM (temp.

< -55°F or temp > 209°F).

UCM Reaction: These unit functions are

disabled:

• supply air tempering

• economizing

• supply air temperature low limit function

(CV units)

• supply air temperature control heating

and cooling functions (VAV units)

Reset Required: (PAR) an automatic reset

occurs after the designated S/A

temperature input returns to its allowable

range. To prevent rapid cycling of the

diagnostic, there is a 10 second delay

before the automatic reset.

Supply Fan Failure

Problem: There is no supply airflow

indication after the supply fan is requested

on.

Check: Check belts, linkages, etc. on the

supply fan assembly. If these are ok, check

field/unit wiring between RTM and supply

fan. If the supply fan runs in service mode,

then verify airflow proving switch and

wiring.

Reason for Diagnostic: The supply airflow

input is detected OPEN for 40 continuous

seconds during any period of time in which

the supply fan binary output is ON.

between 830 ohms (200°F) and 345.7

ohms (-40°F). If so, check field/unit wiring

between the sensor and MCM.

This input is ignored for up to 5 minutes

after the supply fan starts, until airflow is

first detected.

UCM Reaction: “Off” or “Close” requests

are issued as appropriate to the following

functions;

a. Compressor staging/chilled water

control

b. Heat operation

c. Supply fan control & proof of operation

d. Exhaust fan control & proof of operation

e. Exhaust actuator control

f. Economizer actuator control

g. IGV / VFD control

Reset Required: (PMR) A manual reset is

required anytime after the diagnostic is

set. The diagnostic can be reset at the HI,

Tracer Summit, or by cycling power to the

RTM.

Supply Fan VFD Bypass Enabled

a. Data used (module,packet,byte,bit): RTM

b. Activation conditions: supply fan VFD

bypass has been activated and supply fan

vfd bypass is installed.

c. Time to React: 10 sec < T < 20 sec

d. Diagnostic text (human interface display)

SUPPLY FAN VFD BYPASS ENABLED”

e. Actions to be Initiated: NONE

f. Reset: The INFO diagnostic is cleared

when the supply fan VFD bypass is

deactivated.

T

LCI-I Module Comm Failure

Problem: The RTM has lost communication

with the LCI-I.

Check: Check field/unit wiring between

RTM and LCI-I module.

Reason for Diagnostic: The RTM has lost

communication with the LCI-I module.

UCM Reaction: All active commands and

setpoints provided by Tracer Summit

through the LCI-I will be cancelled and/or

ignored. And where Tracer Summit has

been designated as setpoint source, local

HI default setpoints will be used.

Reset Required: (PAR) An automatic reset

occurs after communication has been

restored.

Tracer Communications Failure

Problem: The LCI-I has lost communication

with Tracer Summit.

Check: Tracer Summit (building control

panel) is powered up and running properly.

If so, check unit wiring between LCI-I and

Tracer Summit (building control panel).

Reason for Diagnostic: The LCI-I has lost

communications with Tracer Summit for >

15 minutes.

UCM Reaction: All active commands and

setpoints provided by Tracer Summit

through the LCI-I will be cancelled and/or

ignored. And where Tracer Summit has

been designated as the setpoint source,

local HI default setpoints are used.

diagnosticsMaintenance

112 SCXG-SVX01B-EN

Reset Required: (PAR) An automatic reset

occurs after communication between

Tracer Summit and the LCI-I is restored.

U

Unit HI Communications Failure

Problem: The RTM has lost

communication with the unit mounted

(local) human interface (HI).

Check: Field/unit wiring between RTM

hand local HI.

Reason for Diagnostic: The RTM has lost

communication with the unit-mounted

human interface.

UCM Reaction: A fail-safe function in the HI

will cause the following sequence:

a. disallow any interaction between the HI

and the RTM (or any other modules),

b. render all HI keystrokes ineffective

c. cause the following message to display

on the unit-mounted HI display: “Local

HI communications loss. Check comm

link wiring between modules.” If the unit

has a remote HI option, then this

diagnostic will display as any other

automatic reset diagnostic.

Reset Required: (INFO) An automatic reset

occurs after communication is restored

between the RTM and the HI. When the

failure screen clears, the general display

restores to allow the HI to interact with the

RTM again.

Unoccupied Zone Cool Setpoint Failure

Problem: The unoccupied zone cooling

setpoint input is out of range.

Reason for Diagnostic: The input

designated as the unoccupied zone cooling

setpoint source is out of range (temp <

45°F or temp > 94°F).

UCM Reaction: The active unoccupied

zone cooling setpoint reverts to the default

value.

Reset Required: (PAR) An automatic reset

occurs after the designated unoccupied

zone cool setpoint input returns to its

allowable range for 10 continuous

seconds, or after the user defines a

different, valid unoccupied zone cool

setpoint selection source.

Unoccupied Zone Heat Setpoint Failure

Problem: The unoccupied zone heating

setpoint input is out of range.

Reason for Diagnostic: The input

designated as unoccupied zone heating

setpoint source is out of range (temp < 45

F or temp > 94 F).

UCM Reaction: The active unoccupied

zone heating setpoint reverts to the

default value.

Reset Required: (PAR) An automatic reset

occurs after the designated unoccupied

zone heat setpoint input returns to its

allowable range for 10 continuous

seconds, or after the user defines a

different, valid unoccupied zone heating

setpoint selection source.

V

VCM Communication Failure

Problem: The RTM has lost

communication with the VCM.

Verify: Check field/unit wiring between

RTM and VCM.

Reason for Diagnostic: The RTM has lost

communication with the VCM.

UCM Reaction: All active commands and

setpoints provided by the VCM are

canceled and/or ignored. A fail-safe

function in the VCM will cause all outputs

to deenergize and/or set to zero. The

outside air damper minimum position

function will revert to using the O/A flow

compensation function if O/A flow

compensation is enabled or set to the

default minimum position function if O/A

flow compensation is disabled or not

available.

Reset Required: (PAR) An automatic reset

occurs after communication is restored.

communications with the VOM.

Velocity Pressure Sensor Failure

Problem: The velocity pressure input

signal is out of range.

Check: Check field/unit wiring between

sensor and VCM.

Reason for Diagnostic: The unit is reading a

signal that is out of range for the velocity

pressure transducer input (during

calibration: V < 40 mV or V > 420 mV,

during operation: V < 40 mV or V > 0.75 V).

UCM Reaction: The minimum airflow

control function is disabled. The outside air

damper minimum position function reverts

to using the O/A flow compensation

function if O/A flow compensation is

enabled or to the default minimum position

function if O/A flow compensation is

disabled or not available.

Reset Required: (PAR) An automatic reset

occurs after the designated space pressure

transducer sends a signal within range for

10 continuous seconds.

VOM Communications Failure

Problem: The RTM has lost communication

with the VCM.

Check: Field/unit wiring between RTM and

VCM.

Reason for Diagnostic: The RTM has lost

communications with the VOM.

UCM Reaction: Ventilation override actions

will not be allowed, and the VO Output

relay will be deenergized.

Reset Required: (PAR) An automatic reset

occurs after communication has been

restored.

W

WSM Communications Fail

Problem: The RTM has lost communication

with the WSM.

Check: Field/unit wiring between RTM and

WSM.

Reason for Diagnostic: The RTM has lost

communication with the WSM.

UCM Reaction: The UCM will react as if a

freezestat has occurred by issuing:

• An “all heat on” or “mod output full

open” request to “heat control”

diagnostics

Maintenance

SCXG-SVX01B-EN 113

• A “fan off” request to “supply fan

control”

• A “close damper” request to

“economizer actuator control”

• The water pump to turn on and position

all water valves to provide maximum

flow through all water source heat

exchangers

• Disables preheat function if WSM mixed

air temp sensor is selected as preheat

sensor

Reset Required: An automatic reset

occurs after one complete set of IPC

packets is received.

WSM Mixed Air Temp Sensor Fail

b. Activation Conditions: temperature <

-50°F or temperature > 209°F, and sensor

is selected for use by “waterside

economizer temperature enable

function” or “preheat function”

c. Time to React: 10 sec < T < 20 sec

e. Actions to be Initiated: “waterside

economizer temperature enable

function” uses supply air cooling setpoint

instead of mixed air temperature. If xixed

air temperature is used for “preheat

function”, issue a “disable” request to

“preheat function”.

f. Reset: An automatic reset occurs after

the mixed air temp. input returns to

within range continuously for 10 seconds.

Water Flow Fail

a. Data used (module,packet,byte,bit):

WSM, 01,19, 05

b. Activation Conditions: The water flow

input is detected open ;

1. at the end of precool water flow

initiation state, or

diagnostics

2. continuously for five minutes while:

·water side economizer is open 100%,

· presetting of a head pressure valve, or

· demand for mechanical cooling.

Unit must be: a. configured with water

cooled condenser and/or water

economizer and b. have water flow

switch installed.

c. Time to React: immediate

e. Actions to be Initiated: A “lockout all

ckts” request is issued to the

“compressor staging function”

f. Reset: An automatic reset occurs after

the water flow input returns to within

range continuously for 3 seconds, the

water pump is requested OFF, or the

water flow switch becomes not installed.

Z

Zone Cool Setpoint Failure

Problem: The occupied zone cooling

setpoint is out of range.

Reason for Diagnostic: The input

designated as occupied zone cooling

setpoint source is out of range (temp. <

45°F or temp > 94°F).

UCM Reaction: The active occupied zone

cooling setpoint reverts to the default

occupied zone cooling setpoint.

Reset Required: (PAR) an automatic reset

occurs after the designated occupied

zone CSP input returns to its allowable

range for 10 continuous seconds, or after

a different valid occupied zone CSP

selection source is user-defined.

Maintenance

114 SCXG-SVX01B-EN

SCXG-SVX01B-EN 115

www.trane.com

For more information, contact your local Trane

office or e-mail us at comfort@trane.com

Literature Order Number

Date

Supersedes

Trane has a policy of continuous product and product data improvement and reserves the right to change

design and specifications without notice.

SCXG-SVX01B-EN

March 2008

SCXG-SVX01B-EN July 2000