LENNOX Air Conditioner/heat Pump(outside Unit) Manual L0806498

User Manual: LENNOX LENNOX Air conditioner/heat pump(outside unit) Manual LENNOX Air conditioner/heat pump(outside unit) Owner's Manual, LENNOX Air conditioner/heat pump(outside unit) installation guides

Open the PDF directly: View PDF .
Page Count: 24

LENNOX

,1,_2003Lennox industries inc.

Dallas, Texas

INSTALLATION

INSTRUCTIONS

HPXB15 SERIES UNITS

HEAT PUMP UNITS _ Technical

504,735M i i i_z-_j_LL[Publications

12/03

Supersedes 07/03 Lithe U.S.A.

HPXB15 outdoor units use R410A which is an ozone

friendly HFC refrigerant. This unit must be installed with a

matching indoor coil and line set as outlined in the Lennox

Engineering Handbook. HPXB15 outdoor units are de-

signed for use in expansion valve (TXV) systems only.

They are not designed to be used with other refrigerant flow

control devices. The Lennox Engineering Handbook lists

indoor TXV kits that must be ordered separately.

A, IMPORTANT

HPXB15 Outdoor Unit ........................... 1

Shipping & Packing List ......................... 1

General Information ............................. 1

Dimensions .................................... 2

Parts Arrangement ............................. 3

Setting the Unit ................................. 3

Electrical ...................................... 4

Refrigerant Piping .............................. 6

Refrigerant Metering Device ..................... 6

Flushing Existing Line Set & Indoor Coil ........... 7

Manifold Gauge Set ............................. 8

Service Valves ................................. 8

Leak Testing ................................... 9

Evacuation ................................... 10

Start-Up ...................................... 11

Charging .................................... 11

System Operation ............................. 15

Defrost System ............................... 16

Maintenance .................................. 18

Optional Accessories ........................... 19

Homeowner Information ........................ 19

HPXB15 Check Points ......................... 20

RETAIN THESE INSTRUCTIONS

FOR FUTURE REFERENCE

1 - Assembled HPXB15 outdoor unit

2 - Grommets (for liquid and vapor lines)

Check equipment for shipping damage. If you find any

damage, immediately contact the last carrier.

,A WARNING

These instructions are intended as a general guide and do

not supersede local codes in any way. Consult authorities

who have jurisdiction before installation.

,&,WARNING

12/03

IIIIIIIIIIIIIIIIIIIIIIII1,1111111111111

Page 1

504,735M

IIil!111111,111,111,11111111111111111111111

inlet _ air

compressor

inlet

air

electrical

inlets

vapor

line inlet

liquid

line inlet

4-1/2 (114)

2-3/4

(70)

2 1-3/8

(51) (35)

coil drain outlets

air (around perimeter

Top View of base)

C y

discharge tair

Side View

Model No.

JR.

HPXB15-024

HPXB15-030 in.

HPXB15-036 mm

in.

HPXB15-042 mm

HPXB15-048 in.

HPXB15-060 mm

A B CD E F G HJ

27-7/8 25-7/8 29-7/8 12-1/4 22-7/16 14-7/16 22-1/8 16-3/4 2-7/8

708 657 759 311 570 367 562 425 730

30-7/8 32-1/8 34-1/16 12-3/4 26-5/8 18-5/8 28-1/8 17-1/4 3-7/8

784 816 865 324 676 473 718 438 98

34-7/8 32-1/8 34-1/16 13-3/4 26-5/8 18-5/8 28-1/8 18-1/4 3-7/8

886 816 865 349 676 473 718 464 98

44-7/8 32-1/8 34-1/16 14-1/4 26-5/8 18-5/8 28-1/8 18-3/4 3-7/8

1140 816 865 362 676 473 718 476 98

5-1/2

140

7-1/2

191

7-1/2

191

7-1/2

191

Page 2

high pressure

switch

filter/drier

expansion valve

with internal

system operation

monitor \

defrost control/timed-off control

contactor

ground lug

sensing bulb

vaporline

service valve

and gauge port

liquid line

service valve

and gauge port

defrost

thermostat crankcase heater

thermostat

distributor

compressor

terminal plug crankcase

heater

muffler

reversing valve

and solenoid

Figure 1

ACAUTION

XkCAUTION

These units operate under a wide range of weather condi-

tions; therefore, several factors must be considered when

positioning the outdoor unit. The unit must be positioned to

give adequate clearances for sufficient airflow and servic-

ing. A minimum clearance of 24 inches (610 mm) between

multiple units must be maintained. Refer to figure 2 for in-

stallation clearances.

1 - Place a sound-absorbing material, such as Isomode,

under the unit if it will be installed in a location or posi-

tion that will transmit sound or vibration to the living

area or adjacent buildings.

2 - Mount unit high enough above ground or roof to allow

adequate drainage of defrost water and prevent ice

build-up.

3 - In heavy snow areas, do not locate unit where drifting

will occur. The unit base should be elevated above the

depth of average snows.

NOTE -Elevation of the unit may be accomplished by

constructing a frame using suitable materials. If a sup-

port frame is constructed, it must not block drain holes

in unit base.

Installation Clearances

NOTE -A service access

clearance of 30" (762 mm)

must be maintained in front

of the service access panel.

Clearance to one side must

be 36" (914 mm). Clearance

to one of the remaining two 30"

sides may be 12" (304 mm) (762ram)

and the final side may be 6"

(152 mm).

NOTE -A clearance of 24" (610 mm)

must be maintained between two unit&

as noted _*

I as noted J

NOTE -48" (1219 mm) clearance required on top

of unit. Maximum soffit overhang is 36" (914 mm).

Figure 2

4 - When installed in areas where low ambient tempera-

tures exist, locate unit so winter prevailing winds do

not blow directly into outdoor coil.

Page 3

5- Locateunitawayfromoverhangingrooflineswhich

wouldallowwateroricetodropon,orinfrontof,coilor

intounit,

Slab Mounting

When installing unit at grade level, top of slab should be

high enough above the grade so that water from higher

ground will not collect around unit, See figure 3. Slab

should have a slope tolerance away from the building of 2

degrees or 2 inches per 5 feet (51 mm per 1.5 m), This will

prevent ice build-up under unit during a defrost cycle. Refer

to roof mounting section for barrier construction if unit must

face prevailing winter winds.

2 degrees or

2 in. per 5 foot

(51 mm per 1.5 m) discharge air

slope tolerance away

from building structure %r

ground level

Slab Mounting

Figure 3

building

structure

mounting

slab

CL-

-T

C[-

Roof Mounting

Install the unit a minimum of 6 inches (152 mm) above the

roof surface to avoid ice build-up around the unit. Locate

the unit above a load bearing wall or area of the roof that

can adequately support the unit, Consult local codes for

rooftop applications,

If unit coil cannot be mounted away from prevailing winter

winds, a wind barrier should be constructed. See figure 3,

Size barrier at least the same height and width as outdoor

unit, Mount barrier 24 inches (610 mm) from the sides of the

unit in the direction of prevailing winds.

Rooftop Application

Wind Barrier Construction

prevailing winter winds

wind barrier

inlet air

]IL

24"

(610 ram)

INLET

AIR

Figure 4

In the U,S,A., wiring must conform with current local codes

and the current National Electric Code (NEC). In Canada,

wiring must conform with current local codes and the current

Canadian Electrical Code (CEC),

Refer to the furnace or blower coil installation instructions

for additional wiring application diagrams and refer to unit

nameplate for minimum circuit ampacity and maximum

overcurrent protection size.

WARNING

1 -Install line voltage power supply to unit from a properly

sized disconnect switch,

2 -Ground unit at unit disconnect switch or to an earth

ground.

Page 4

NOTE -To facilitate conduit, a hole is in the bottom of

the control box. Connect conduit to the control box us

ing a proper conduit fitting.

NO TE -Units are approved for use only with copper

conductors.

24V, Class II circuit connections are made in the low

voltage junction box. Refer to figure 5 for field wiring

diagram.

NOTE -A complete unit widn_l dia_lram is located in

side the unit control box cover.

3 - Install room thermostat (ordered separately) on an in-

side wall approximately in the center of the conditioned

area and 5 feet (1.5 m) from the floor. It should not be

installed on an outside wall or where it can be affected

by sunlight, drafts or vibrations.

4 - Install voltage wiring from outdoor to indoor unit and

from thermostat to indoor unit. See figures 6 and 7.

Typical Field Wiring Diagram

OUTDOOR FAN

(LEADED) ORANGE-RUN

=COMMON

PURPLE=

CAPACITOR

CI2

DUAL

CAPACITOR

SYSTEM

OPERATION

MONITOR E _--- WI

AN DEFROST

Y,OUT CONTROL

HI -PS

L0-PS

_ RO

D! wo

OUT Y I

GROUND

LUG,S_

COMPRESSOR

DONTACTOR

Ik,

L2 L1

208-230/60/1

main power

z_NOTE-

FOR USE WITH COPPER CONDUCTORS

ONLY.REFER TO UNIT RATING

PLATE FOR MINIMUM CIRCUIT

AMPACITY AND MAXIMUM OVER-

CURRENT PROTECTION SIZE

/_ WARNING-

ELECTRIC SHOCK HAZARD,CAN CAUSE INJURY

OR DEATH.UNIT MUST BE GROUNDED IN

ACCORDANCE WITH NATIONAL AND LOCAL CODES.

Figure 5

Page 5

Outdoor Unit and Blower Unit

Thermostat Designations

(Some connections may not apply.

Refer to specific thermostat and indoor unit.)

Thermostat Indoor Outdoor

Unit Unit

power

common _(__

1st. stage aux. heat _F

indoor blower -(b

reversing valve

power

common

1st. s_e aux. hea_l

compressor

Figure 6

Outdoor Unit and Blower Unit

Thermostat Designations

(with auxiliary heat)

(Some connections may not apply.

Refer to specific thermostat and indoor unit.)

Thermostat

power 1_

common I

emergency heat I -

1st. stage aux. TTeaq-

indoor btower

reversinq.vatve

Indoor

Unit

__. power

he_"cOmmat_em'_

/eutdger t'stat

-_-st._stTg _. _at

®1

compressor

Outdoor

Unit

®1

®[

®1

Figure 7

If the HPXB15 unit is being installed with a new indoor coil

and line set, the refrigerant connections should be made as

outlined in this section. If an existing line set and/or indoor

coil is going to be used to complete the HPXB15 system,

refer to the following section which includes flushing proce-

dures.

Field refrigerant piping consists of liquid and vapor lines

from the outdoor unit (sweat connections) to the indoor coil

(flare or sweat connections). Use Lennox L15 (sweat, non-

flare) series line sets as shown in table 1 or use field-fabri-

cated refrigerant lines, Valve sizes are listed in table 1.

Refrigerant Connections

HPXB15 Matched with New Indoor Coil and Line Set

If an existing indoor coil which was equipped with an

RFCI metering device is being replaced, the liquid line

must also be replaced prior to the installation of the

HPXB15 unit.

Table 1

Refrigerant Line Sets

Valve Field Size Recommended Line Set

Connections

Model L15

Liquid Vapor Liquid Vapor Line Sets

Line Line Line Line

-024 3/8 in, 3/4 in, 3/8 in, 3/4 in, L15-41

-030 10mm 19mm 10mm 19mm 15 ft. - 50 ft.

-036 4.6 m- 15 m

-042 3/8 in. 7/8 in. 3/8 in. 7/8 in. L15-65

-048 10mm 22mm 10mm 22mm 15 ft. - 50 ft.

4.6m- 15m

3/8 in, 1-1/8 in, 3/8 in. 1-1/8 in, Field

-060 10 mm 29 mm 10 mm 29 mm Fabricated

NOTE -Units are designed for line sets of up to 50 feet (15

m). Select line set diameters from table 1 to ensure that oil

returns to the compressor.

Installing Refrigerant Line

During the installation of any heat pump or a/c system, it is

important to properly isolate the refrigerant lines to prevent

unnecessary vibration, Line set contact with the structure

(wall, ceiling or floor) causes some objectionable noise

when vibration is translated into sound, As a result, more

energy or vibration can be expected, Closer attention to

line set isolation must be observed,

Following are some points to consider when placing and

installing a high-efficiency outdoor unit:

1-Placement - Be aware some localities are adopting

sound ordinances based on how noisy the unit is from

the adjacent property not at the original installation.

Install the unit as far as possible from the property line,

When possible, do not install the unit directly outside a

window, Glass has a very high level of sound transmis-

sion.

2- Line Set Isolation -The following illustrations demon-

strate procedures which ensure proper refrigerant line

set isolation. Figure 8 shows how to install line sets on

vertical runs. Figure 9 shows how to install line sets on

horizontal runs, Figure 10 shows how to make a transi-

tion from horizontal to vertical, Finally, figure 11 shows

how to place the outdoor unit and line set,

Page 6

Refrigerant Line Sets

How To Install Vertical Runs

(new construction shown)

NOTE -Similar installation practices should be used if

line set is to be installed on exterior of outside waft.

Outside Wall

Wood Block

Between Studs

-Vapor LiLn_uid Lin-'_

(wrapped with

Outside Wall

g__Caulk

PVC Pipe Fiberglass

Insulation

IMPORTANT- Refrigerant

lines must not contact

structure, j

IMPORTANT- Refrigerant

lines must not contact wall. Vapor Line Liquid Line

Wire Tie

\ Inside Wall

-- Strap

_ Sleeve

_- Wire Tie

--_------- Wood Block

"_ _-------- Wire Tie

Strap

_" _ Sleeve

Figure 8

Page 7

Refrigerant Line Sets:

Installing Horizontal Runs

To hang line set from joist or rafter,

use either metal strapping material

or anchored heavy nylon wire ties.

8 feet

Floor Joist or

Roof Rafter

8 feet

Wire Tie

(around vapor line only)

Tape or Wire Tie

Strapping Material (around vapor line only)

Tape or Wire Tie

Metal Sleeve

r j/

, Floor Joist or Roof Rafterf_

Strap the vapor line to the joist or rafter at 8 ft.

intervals then strap the liquid line to the vapor line.

Figure 9

Page 8

AnchoredHeavy

NylonWireTie

Refrigerant Line Sets:

Transition From Vertical To Horizontal

Automotive

Muffler-Type

Hanger

Wall

Stud Strap Liquid Line

To Vapor Line

Wall

Stud

Strap Liquid Line

To Vapor Line

Liquid Line

Sleeve

Vapor Line

Wrapped in

Armaflex Liquid Line

Figure 10

Metal

Sleeve

Vapor Line

Wrapped in

Armaflex

Outside Unit Placement and Installation

Install unit away from windows. J

Two 90° elbows

installed in line set

will reduce line set

vibration.

Figure 11

Page 9

IsolationGrommets

Locatetheprovidedisolationgrommets.Usea knifetoslit

thewebbingoneachgrommet.Slidelargergrommetonto

vaporlineand smallergrommetontoliquidline.Insert

grommetsinto mullionto isolaterefrigerantlinesfrom

sheetmetaledges.

&WARNING

Brazing Connection Procedure

1 - The end of the refrigerant line must be cut square and

its internal shape must remain round. The line must be

free of nicks or dents and must be deburred (I.D. and

O.D.)

2 - Before making line set connections, use dry nitrogen to

purge the refrigerant piping. This will help to prevent

oxidation and the introduction of moisture into the sys-

tem.

3 - Use silver alloy brazing rods (5 or 6 percent minimum

silver alloy for copper-to-copper brazing or 45 percent

silver alloy for copper4o-brass or copper4o-steel braz-

ing). Wrap a wet cloth around the valve body and the

copper tube stub. Remove light maroon washers from

service valves and shield light maroon stickers in order

to protect them during brazing. Braze the line set to the

service valve.

4 - Quench the joint with water or a wet cloth to prevent

heat damage to the valve core and opening port.

IMPORTANT -The tube end must stay bottomed in the

fitting during final assembly to ensure proper seating,

sealing and rigidity.

Metering Device Installation

distributor

o-ring

expanston

valve j

liquid li_

stub

Figure

&IMPORTANT

&WARNING

&IMPORTANT

HPXB15 units are used in check expansion valve systems

only. Check expansion valves equipped with Chatleff fit-

tings are available from Lennox. Refer to the Engineering

Handbook for applicable expansion valves for use with

specific match-ups.

If you install a check expansion valve with an indoor coil

that includes a fixed orifice, remove the orifice before

installing the check expansion valve.

See figure 12 for installation of the check expansion valve.

Page 10

ACAUTION

IMPORTANT

Required Equipment

You will need the following equipment in order to flush the

existing line set and indoor coil: two clean R22 recovery

bottles, an oilless recovery machine with a pump down fea-

ture, and two sets of gauges (one for use with R22 and one

for use with the R410A).

Flushing Procedure

1 - Remove existing R22 refrigerant using the appropri-

ate procedure below.

If the existing outdoor unit is not equipped with

shut-off valves, or if the unit is not operational

AND you plan to use the existing R22 refrigerant to

flush the system -- Disconnect all power to the exist-

ing outdoor unit. Connect the existing unit, a clean re-

covery cylinder and the recovery machine according

to the instructions provided with the recovery ma-

chine, Remove all R22 refrigerant from the existing

system. Refer to gauges after shutdown to confirm

that the entire system is completely void of refrigerant.

Disconnect the liquid and vapor lines from the existing

outdoor unit,

ff the existing outdoor unit is equipped with manu-

al shut-off valves AND you plan to use NEW R22

refrigerant to flush the system -- Start the existing

R22 system in the cooling mode and close the liquid

line valve, Pump all of the existing R22 refrigerant

back into the outdoor unit, (It may be necessary to by-

pass the low pressure switches to ensure complete re-

frigerant evacuation,) When the low side system pres-

sures reach 0 psig, close the vapor line valve.

Disconnect all power to the existing outdoor unit, Re-

fer to gauges after shutdown to confirm that the valves

are not allowing refrigerant to flow back into the low

side of the system, Disconnect the liquid and vapor

lines from the existing outdoor unit,

Remove the existing outdoor unit, Set the new R410A

unit and follow the brazing connection procedure

which begins on the previous page to make line set

connections. DO NOT install the field-provided

R410A check/expansion valve at this time.

Make low voltage and line voltage connections to the

new outdoor unit. DO NOT turn on power to the unit

or open the outdoor unit service valves at this

time.

Remove the existing refrigerant flow control orifice or

thermal expansion/check valve before continuing with

flushing procedures. The existing devices are not ap-

proved for use with R410A refrigerant and may pre-

vent proper flushing, Use a field-provided fitting to re-

connect the lines.

Page 11

Existinc

Indoor Coil

RECOVERY

CYLINDER

Inverted R22 Cylinder

(Contains clean R22 to

be used for flushing)

EXISTING VAPOR LINE

EXISTING LIQUID LINE

Flushing Connections

TANK RETURN

INLET

DISCHARGE

Recovery Machine

HPXB15 Unit

LOW HIGH

PRESSURE PRESSURE

Op{_C:[ENIE:AU GE MAN::_: _:_

NOTE -The inverted R22 cylinder must con-

tain at least the same amount of refrigerant

as was recovered from the existing system.

A, IMPORTANT

Figure 13

4- Remove the pressure tap valve cores from the

H PXB 15 unit's service valves, Connect an R22 cylin-

der with clean refrigerant to the vapor service valve.

Connect the R22 gauge set to the liquid line valve and

connect a recovery machine with an empty recovery

tank to the gauge set,

5 - Set the recovery machine for liquid recovery and start

the recovery machine, Open the gauge set valves to

allow the recovery machine to pull a vacuum on the ex-

isting system line set and indoor coil,

6 - Invert the cylinder of clean R22 and open its valve to

allow liquid refrigerant to flow into the system through

the vapor line valve, Allow the refrigerant to pass from

the cylinder and through the line set and the indoor coil

before it enters the recovery machine,

After all of the liquid refrigerant has been recovered,

switch the recovery machine to vapor recovery so that

all of the R22 vapor is recovered,

NOTE- A single system flush should remove all of the

mineral oil from the existing refrigerant lines and in-

door coil. A second flushing may be done (using clean

refrigerant) if insufficient amounts of mineral oil were

removed during the first flush. Each time the system

is flushed, you must allow the recovery machine

to pull avacuum on the system at the end of the

procedure.

8- Close the valve on the inverted R22 drum and the

gauge set valves, Pump the remaining refrigerant out

of the recovery machine and turn the machine off,

9 - Use nitrogen to break the vacuum on the refrigerant

lines and indoor coil before removing the recovery ma-

chine, gauges and R22 refrigerant drum, Reinstall

pressure tap valve cores into HPXB15 service valves,

10 -Install the provided check/expansion valve (approved

for use with R410A refrigerant) in the liquid line at the

indoor coil,

Page 12

AIMPORTANT

Access the liquid line and vapor line service valves (figures

14 and 15) and gauge ports are used for leak testing, eva-

cuating, charging and checking charge, See table 2 for

torque requirements,

Each valve is equipped with a service port which has a fac-

tory-installed Schrader valve. A service port cap protects

the Schrader valve from contamination and serves as the

primary leak seal,

Table 2

Torque Requirements

Part Recommended Torque

Service valve cap 8 ft.- lb. 11 NM

Sheet metal screws 16 in.- lb. 2 NM

Machine screws #10 28 in.-lb. 3 NM

Compressor bolts 90 in.- lb. 10 NM

Gauge port seal cap 8 ft.- lb. 11 NM

IMPORTANT

To Access Schrader Port:

1 - Remove service port cap with an adjustable wrench,

2 - Connect gauge to the service port.

3 - When testing is complete, replace service port cap,

Tighten finger tight, then an additional 1/6 turn,

To Open Service Valve:

1 - Remove stem cap with an adjustable wrench.

2 - Using service wrench and hex head extension, back

the stem out counterclockwise as far as it will go,

NO TE -Use a 3/16" hex head extension for liquid line

sizes or a 5/16" extension for vapor line sizes.

3 - Replace stem cap and tighten it firmly. Tighten finger

tight, then tighten an additional 1/6 turn.

To Close Service Valve:

1 - Remove stem cap with an adjustable wrench,

2 - Using service wrench and hex head extension, turn

stem clockwise to seat valve, Tighten it firmly,

NOTE -Use a 3/16" hex head extension for liquid line

sizes or a 5/16" extension for vapor line sizes.

3 - Replace stem cap. Tighten finger tight, then tighten an

additional 1/6 turn.

Vapor Line (Ball Type) Valve

Vapor line service valves function the same way as the oth-

er valves, the difference is in the construction, These

valves are not rebuildable. If a valve has failed, you must

replace it. A ball valve valve is illustrated in figure 15,

The ball valve is equipped with a service port with a factory-

installed Schrader valve. A service port cap protects the

Schrader valve from contamination and assures a leak-

free seal,

Liquid Service Valve (Valve Open)

Insert Hex Stem Cap

Wrench

Field Side

Schrader

Valve

Service Port

Cap

Service Port

Unit Side

Liquid Service Valve (Valve Closed)

Field Side _..----._ Stem Cap

Insert Hex

Wrench Here

Service

Port (Valve Front

Seated)

Service Port Unit Side

Cap

Schrader Valve Open

To Line Set When Valve Is

Closed(FrontSeated)

Figure 14

Page 13

Vapor Line (Ball Type) Service Valve

(Valve Open)

Use Adjustable Wrench

To open: rotate stem counter-clockwise 90 ° .

To close: rotate stem clockwise 90 °.

_service port

cap unit side

Scharlavder_

service

port

ste m

field side ball

(shown open)

Figure 15

stem cap

After the line set has been connected to the indoor and out-

door units, the line set connections and indoor unit must be

checked for leaks.

WARNING

3 - Open the high pressure side of the manifold to allow

the R410A into the line set and indoor unit. Weigh in a

trace amount of R410A. [A trace amount is a maximum

of 2 ounces (57 g) or 3 pounds (31 kPa) pressure.]

Close the valve on the R410A cylinder and the valve

on the high pressure side of the manifold gauge set.

Disconnect the R410A cylinder.

4 - Connect a cylinder of nitrogen with a pressure regulat-

ing valve to the center port of the manifold gauge set.

5 - Connect the manifold gauge set high pressure hose to

the vapor valve service port. (Normally, the high pres-

sure hose is connected to the liquid line port; however,

connecting it to the vapor port better protects the man-

ifold gauge set from high pressure damage.)

6 - Adjust the nitrogen pressure to 150 psig (1034 kPa).

Open the valve on the high side of the manifold gauge

set which will pressurize line set and indoor unit.

7 - After a few minutes, open a refrigerant port to ensure

the refrigerant you added is adequate to be detected.

(Amounts of refrigerant will vary with line lengths.)

Check all joints for leaks. Purge nitrogen and R410A

mixture. Correct any leaks and recheck.

,IMPORTANT

AWARNING

WARNING

Using an Electronic Leak Detector

1 - Connect a cylinder of R410A to the center port of the

manifold gauge set.

2 - With both manifold valves closed, open the valve on

the R410A cylinder (vapor only).

Evacuating the system of noncondensables is critical for

proper operation of the unit. Noncondensables are defined

as any gas that will not condense under temperatures and

pressures present during operation of an air conditioning

system. Noncondensables and water vapor combine with

refrigerant to produce substances that corrode copper pip-

ing and compressor parts.

AIMPORTANT

1 - Connect the manifold gauge set to the service valve

ports as follows:

• low pressure gauge to vapor line service valve

• high pressure gauge to liquid line service valve

Close manifold gauge set valves. Connect the center

manifold hose to an upright cylinder of R410A.

2 - Connect micron gauge,

3 - Connect the vacuum pump (with vacuum gauge) to the

center port of the manifold gauge set.

4 - Open both manifold valves and start vacuum pump,

Page 14

5- Evacuatethelinesetandindoorunitto anabsolute

pressureof23,000microns(29.01inchesof mercu-

ry).Duringtheearlystagesof evacuation,it isdesir-

abletoclosethemanifoldgaugevalveatleastonceto

determineifthereisa rapidriseinabsolute pressure.

A rapid rise in pressure indicates a relatively large leak.

If this occurs, repeat the leak testing procedure.

NOTE -The term absolute pressure means the total

actual pressure within a given volume or system,

above the absolute zero of pressure. Absolute pres-

sure in a vacuum is equal to atmospheric pressure mi-

nus vacuum pressure.

6 - When the absolute pressure reaches 23,000 microns

(29.01 inches of mercury), close the manifold gauge

valves, turn off the vacuum pump and disconnect the

manifold gauge center port hose from vacuum pump.

Attach the manifold center port hose to a nitrogen cylin-

der with pressure regulator set to 150 psig (1034 kPa)

and purge the hose. Open the manifold gauge valves

to break the vacuum in the line set and indoor unit.

Close the manifold gauge valves.

XkWARNING

7 - Shut off the nitrogen cylinder and remove the manifold

gauge hose from the cylinder. Open the manifold

gauge valves to release the nitrogen from the line set

and indoor unit.

8 - Reconnect the manifold gauge to the vacuum pump,

turn the pump on, and continue to evacuate the line set

and indoor unit until the absolute pressure does not

rise above 500 microns (29.9 inches of mercury) within

a 20-minute period after shutting off the vacuum pump

and closing the manifold gauge valves.

9 - When the absolute pressure requirement above has

been met, disconnect the manifold hose from the vacu-

um pump and connect it to an upright cylinder of R410A

refrigerant. Open the manifold gauge valves to break

the vacuum from 1 to 2 psig positive pressure in the line

set and indoor unit. Close manifold gauge valves and

shut off the R410A cylinder and remove the manifold

gauge set,

IMPORTANT

1 - Rotate fan to check for frozen bearings or binding.

2 - Inspect all factory- and field-installed wiring for loose

connections.

3 - After evacuation is complete, open the liquid line and

vapor line service valves (counterclockwise) to release

refrigerant charge (contained in outdoor unit) into the

system.

4 - Replace stem caps and secure finger tight, then tight-

en an additional (1/6) one-sixth of a turn.

5- Check voltage supply at the disconnect switch. The

voltage must be within the range listed on the unit

nameplate. If not, do not start the equipment until the

power company has been consulted and the voltage

condition has been corrected.

6 - Set the thermostat for a cooling demand, turn on power

to indoor blower unit and close the outdoor unit discon-

nect to start the unit.

7 - Recheck voltage while the unit is running. Power must

be within range shown on the nameplate.

This system is charged with R410A refrigerant which oper-

ates at much higher pressures than R22. The check/ex-

pansion valve provided with the unit is approved for use

with R410A. Do not replace it with a valve designed for use

with R22. This unit is NOT approved for use with coils which

include metering orifices or capillary tubes.

Processing Procedure

The unit is factory-charged with the amount of R410A re-

frigerant indicated on the unit rating plate. This charge is

based on a matching indoor coil and outdoor coil with a 15

foot (4.6 m) line set. For varying lengths of line set, refer to

table 3 for refrigerant charge adjustment.

Table 3

Liquid Line Set Oz. per 5 ft. (grams per 1.5 m) adjust

Diameter from 15 ft. (4.6 m) line set*

3/8 in. 3 ounces per 5 feet

(10 ram) (85g per 1.5 m)

*If line length is ,reater than 15 ft. (4.6 m), add this amount.

If line length is less than 15 ft. (4.6 m), subtract this amount.

klMPORTANT

Page 15

The compressor is charged with sufficient polyol ester

oil for line set lengths up to 50 ft.

The outdoor unit should be charged during warm weather.

However, applications arise in which charging must occur

in the colder months. The method of charging is deter-

mined by the unit's refrigerant metering device and the out-

door ambient temperature.

Measure the liquid line temperature and the outdoor ambi-

ent temperature as outlined below:

1- Connect manifold gauge set to service valves as

shown in figure 17:

• low pressure gauge to vapor valve service port

• high pressure gauge to liquid valve service port

Connect the center manifold hose to an upright cylin-

der of R410A, Close manifold gauge set valves.

2 - Set the room thermostat to call for heat. This will create

the necessary load for properly charging the system in

the cooling cycle.

3 - Use a digital thermometer to record the outdoor ambi-

ent temperature,

4 - When the heating demand has been satisfied, switch

the thermostat to cooling mode with a set point of 68_F

(20<%). When pressures have stabilized, use a digital

thermometer to record the liquid line temperature,

5 - The outdoor temperature will determine which charg-

ing method to use, Proceed with the appropriate charg-

ing procedure.

Weighing in the Charge TXV Systems -

Outdoor Temp. < 65°F (18°C)

If the system is void of refrigerant, or if the outdoor ambient

temperature is cool, the refrigerant charge should be

weighed into the unit. Do this after any leaks have been re-

paired.

1 - Recover the refrigerant from the unit.

2 - Conduct a leak check, then evacuate as previously

outlined.

3 - Weigh in the unit nameplate charge.

If weighing facilities are not available or if you are charging

the unit during warm weather, follow one of the other proce-

dures outlined below.

Subcooling Method

Outdoor Temp. < 65°F (18°C)

When the outdoor ambient temperature is below 65°F

(18°C), use the subcooling method to charge the unit, It

may be necessary to restrict the air flow through the out-

door coil to achieve pressures in the 325-375 psig

(2240-2585 kPa) range, These higher pressures are nec-

essary for checking the charge. Block equal sections of air

intake panels and move obstructions sideways until the liq-

uid pressure is in the 325-375 psig (2240-2585 kPa) range.

See figure 16,

O,ock,n00u,0oorCoi,

| *Outdoor coil should be

| blocked one side

| at a time with cardboard

| or plastic sheet until proper

r testing pressures

are reached.

cardboard or *4-sided

plastic sheet unit shown

Figure 16

1 - With the manifold gauge hose still on the liquid service

port and the unit operating stably, use a digital ther-

mometer to record the liquid line temperature.

2 - At the same time, record the liquid line pressure reading.

3 - Use a temperature/pressure chart for R410A to deter-

mine the saturation temperature for the liquid line pres-

sure reading. See table 7.

4 - Subtract the liquid line temperature from the saturation

temperature (according to the chart) to determine sub-

cooling. (Saturation temperature - Liquid line tem-

perature = Subcooling)

5 - Compare the subcooling value with those in table 4, If

subcooling is greater than shown, recover some refrig-

erant. If subcooling is less than shown, add some re-

frigerant, Be aware of the R410A refrigerant cylinder. It

will be light maroon-colored, Refrigerant should be

added through the vapor line valve in the liquid state.

Some R410A cylinders are equipped with a dip

tube that allows you to draw liquid refrigerant from

the bottom of the cylinder without turning the cyl-

inder upside-down. The cylinder will be marked if it

is equipped with a dip tube.

Table 4

Subcooling Values for Charging

Model Number Subcooling Values

Conversion Temp. - Liquid Line Temp. °F (°C)

HPXB15-024 5 + 1 (2.8 + .5)

HPXB15-030 8 + 1 (7.4 + .5)

HPXB15-036 5.5 + 1 (3 + .5)

HPXB15-042 4.5 + 1 (2.5 + .5)

HPXB15-048 2.5 + 1 (1.4 + .5)

HPXB15-060 6 + 1 (3.3 + .5)

Charging Using Normal Operating Pressures

and the Approach Method

Outdoor Temp. _>65°F (18°C)

The following procedure is intended as a general guide and

is for use on expansion valve systems only. For best results,

indoor temperature should be 70°F (21°C) to 80°F (26°C),

Monitor system pressures while charging.

1 - Record outdoor ambient temperature using a digital

thermometer.

2 - Attach high pressure gauge set and operate unit for

several minutes to allow system pressures to stabilize,

Page 16

3- Comparestabilizedpressureswiththoseprovidedin

table6, <'NormalOperatingPressures."Minorvaria-

tionsinthesepressuresmaybeexpectedduetodiffer-

encesin installations,Significantdifferencescould

meanthatthesystemisnotproperlychargedorthata

problemexistswithsomecomponentinthesystem.

Pressureshigherthanthoselistedindicatethatthe

systemis overcharged.Pressureslowerthanthose

listedindicatethatthesystemisundercharged,Verify

adjustedchargeusingtheapproachmethod.

ApproachMethod

4 - Usethesamedigitalthermometerusedtocheckout-

doorambienttemperaturetocheckliquidlinetempera-

ture.Verifytheunitchargeusingtheapproachmethod,

5- Thedifferencebetweentheambientandliquidtemper-

aturesshouldmatchvaluesgivenintable5.Iftheval-

uesdon'tagreewiththethoseintable5,addrefriger-

ant to lowerthe approachtemperatureor recover

refrigerantfromthesystemto increasetheapproach

temperature,

Table 5

Approach Values for Charging

Approach Temperature

Model Number Liquid Line Temp. -Outdoor Ambient °F (°C)

HPXB15-024 13 + 1 (7.2 + .5)

HPXB15-030 7 + 1 (3.9 + .5)

HPXB15-036 11 + 1 (6.1 + .5)

HPXB15-042 12.5 + 1 (6.9 + .5)

HPXB15-048 10 + 1 (5.6 + .5)

HPXB15-060 11.5 + 1 (6.5 + .5)

IMPORTANT

HPXB15 Cooling Cycle

(Showing Gauge Manifold Connections)

DEFROST THERM OSTAT-_._._ I

EXPANSION/ I

CHECK VALVE __

LOW HIGH

PRESSURE PRESSURE

°OAI

DRU=[[ sc y47St

OUTDOOR UNIT

DISTRIBUTOR

FILTER /OUTDOOR

1_ DR,ER CO,L

-- -- --I--'_ COMPRESSO_

NOTE-Use gauge ports on vapor line valve and liquid valve for evacuating refrigerant lines

and indoor coil. Use vapor gauge port to measure vapor pressure during charging.

NOTE - ARROWS INDICATE

DIRECTION OF REFRIGERANT

REVERSING VALVE FLOW

INDOOR UNIT

_X VAPOR

SERVICE

POR__ VAPOR

/LINE

VALVE

INDOOR

EXPANSION/CHECK COIL

VALVE L ......

Figure 17

Page 17

Table 6

Normal Operating Pressures

(Liquid +10 and Vapor +5 psig)

Cooling Operation

Outdoor Coil HPXB15-024 HPXB15-030 HPXB15-036 HPXB15-042 HPXB15-048 HPXB15-060

Entering Air

Temp. °F (°C) Liquid Vapor Liquid Vapor Liquid Vapor Liquid Vapor Liquid Vapor Liquid Vapor

65 (18.3) 252 131 233 141 216 136 240 133 228 137 231 124

75 (23.9) 291 133 272 142 276 138 281 135 265 139 269 126

85 (29.4) 337 135 314 143 298 139 325 137 304 141 315 127

95 (35.0) 371 140 360 146 359 141 372 138 348 142 370 133

105 (40.6) 421 142 413 148 400 143 428 142 405 145 415 136

Heating Operation

Outdoor Coil HPXB15-024 HPXB15-030 HPXB15-036 HPXB15-042 HPXB15-048 HPXB15-060

Entering Air

Temp. °F (°C) Liquid Vapor Liquid Vapor Liquid Vapor Liquid Vapor Liquid Vapor Liquid Vapor

20 (-6.6) 288 60 270 67 234 62 340 65 313 60 245 55

30 (-1.1) 306 75 297 84 257 80 350 72 330 73 287 66

40 (4.4) 325 90 325 100 318 93 353 83 346 87 332 82

50 (10.0) 344 105 353 117 322 103 358 101 366 101 347 99

Table 7

R410A Temperature/Pressure Chart

Temperature Pressure Temperature Pressure Temperature Pressure Temperature Pressure

°F Psig °F Psig °F Psig °F Psig

32 100.8 63 178.5 94 290.8 125 445.9

33 102.9 64 181.6 95 295.1 126 451.8

34 105.0 65 184.3 96 299.4 127 457.6

35 107.1 66 187.7 97 303.8 128 463.5

36 109.2 67 190.9 98 308.2 129 469.5

37 111.4 68 194.1 99 312.7 130 475.6

38 113.6 69 197.3 100 317.2 131 481.6

39 115.8 70 200.6 101 321.8 132 487.8

40 118.0 71 203.9 102 326.4 133 494.0

41 120.3 72 207.2 103 331.0 134 500.2

42 122.6 73 210.6 104 335.7 135 506.5

43 125.0 74 214.0 105 340.5 136 512.9

44 127.3 75 217.4 106 345.3 137 519.3

45 129.7 76 220.9 107 350.1 138 525.8

46 132.2 77 224.4 108 355.0 139 532.4

47 134.6 78 228.0 109 360.0 140 539.0

48 137.1 79 231.6 110 365.0 141 545.6

49 139.6 80 235.3 111 370.0 142 552.3

50 142.2 81 239.0 112 375.1 143 559.1

51 144.8 82 242.7 113 380.2 144 565.9

52 147.4 83 246.5 114 385.4 145 572.8

53 150.1 84 250.3 115 390.7 146 579.8

54 152.8 85 254.1 116 396.0 147 586.8

55 155.5 86 258.0 117 401.3 148 593.8

56 158.2 87 262.0 118 406.7 149 601.0

57 161.0 88 266.0 119 412.2 150 608.1

58 163.9 89 270.0 120 417.7 151 615.4

59 166.7 90 274.1 121 423.2 152 622.7

60 169.6 91 278.2 122 428.8 153 630.1

61 172.6 92 282.3 123 434.5 154 637.5

62 195.5 93 286.5 124 440.2 155 645.0

Page 18

Theoutdoorunitandindoorblowercycleondemandfrom

theroomthermostat.Whenthethermostatblowerswitchis

intheONposition,theindoorbloweroperatescontinuously.

ThermostatOperation

Someoutdoorthermostatsincorporateisolatingcontacts

andanemergencyheatfunction(whichincludesanamber

indicatinglight).Thethermostatisnotincludedwiththeunit

andmustbepurchasedseparately,

EmergencyHeat(AmberLight)

Anemergencyheatfunctionisdesignedintosomeroomther-

mostats.Thisfeatureisapplicablewhenisolationoftheout-

doorunitisrequired,orwhenauxiliaryelectricheatisstaged

byoutdoorthermostats,Whentheroomthermostatisplaced

intheemergencyheatposition,theoutdoorunitcontroldrcuit

is isolatedfrompowerandfield-providedrelaysbypassthe

outdoorthermostats,Anamberindicatinglightsimultaneously

comesontoremindthehomeownerthatheisoperatinginthe

emergencyheatmode,

Emergencyheatis usuallyusedduringan outdoorunit

shutdown,butitshouldalsobeusedfollowinga powerout-

ageif powerhasbeenoffforoveranhourandtheoutdoor

temperatureisbelow50°F(10°C).Systemshouldbeleftin

theemergencyheatmodeatleastsixhoursto allowthe

crankcaseheatersufficienttimeto preventcompressor

slugging.

HighPressureSwitch

TheHPXB15isequippedwithanauto-resethighpressure

switchwhichis locatedon theliquidline.Thenormally

closedswitchopensthe compressorcircuitwhendis-

chargepressurerisesabove640+ 10psig(4412+ 69

kPa),Theswitchautomaticallycloseswhendischarge

pressurefallsbelow448+ 10psig(3089+ 69kPa),

FilterDrier

Theunitisequippedwitha large-capacitybifiowfilterdrier

whichkeepsthesystemcleananddry.If replacementis

necessary,orderanotheroflikedesignandcapacity.The

replacementfilterdriermustbesuitableforusewithR410A

refrigerant,

System Operation Monitor

The system operation monitor detects the most common

fault conditions in the air conditioning system,

When an abnormal condition is detected, the module com-

municates the specific condition through its ALERT and

TRIP lights. The monitor is capable of detecting both me-

chanical and electrical system problems, See figure 18 for

the system operation monitor

A, IMPORTANT

System Operation Monitor

LED

LED's

Figure 18

LED Functions

See table 8 for LED troubleshooting diagnostic codes.

Power LED (green) - indicates voltage within the range of

19-28VAC is present at the power connection of the monitor.

Alert LED (yellow) - communicates an abnormal system

condition through a unique flash code, The alert LED will

flash a number of times consecutively, pause and then re-

peat the process. The number of consecutive flashes, de-

fined as the Flash Code, correlates to a particular abnormal

condition,

Trip LED (red) - indicates there is a demand signal from the

thermostat but no current to the compressor is detected by

the module,

TRIP and ALERT LEDs flashing at the same time indicates

that the control circuit voltage is too low for operation.

Reset ALERT flash code by removing 24VAC power from

monitor. Last ALERT flash code will display for 1 minute af-

ter monitor is powered on,

Page 19

Table 8

System Operation Monitor LED Troubleshooting Codes

Status LED Status LED Description Status LED Troubleshooting Information

Green "Power" Module has power. 24MAC control power is present at the module terminal.

1 Compressor protector is open.

Thermostat demand signal 2 Outdoor unit power disconnect is open.

Y1 is present, but the com- 3 Compressor circuit breaker or fuse(s) is open.

Red "Trip" pressor is not running. 4 Broken wire or connector is not making contact.

5Low pressure switch open if present in the system.

6 Compressor contactor has failed to close.

Low refrigerant charge.

Yellow "Alert" 2Evaporator blower is not running.

Flash Code 1 Long Run Time 3Evaporator coil is frozen.

(Does not apply to heat Compressor is running ex- 4 Faulty metering device.

pump or to two-stage tremely long run cycles 5 Condenser coil is dirty

split systems) 6 Liquid line restriction (filter drier blocked if present)

7 Thermostat is malfunctioning.

System Pressure Trip _ High head pressure.

Yellow "Alert" Discharge or suction pres- 2 Condenser coil poor air circulation (dirty, blocked, damaged).

Flash Code 2 sure out of limits or 3Condenser fan is not running.

compressor overloaded 4 Return air duct has substantial leakage.

5 If low pressure switch is present, check Flash Code 1 information.

Short Cycling I Thermostat demand signal is intermittent.

Yellow "Alert" Compressor is 2 Time delay relay or control board is defective.

Flash Code 3 running 3If high pressure switch is present, check Flash Code 2 information.

only briefly 4 If low pressure switch is present, check Flash Code 1 information.

Yellow "Alert" _ Run capacitor has failed.

2 Low line voltage (contact utility if voltage at disconnect is low).

Flash Code 4 Locked Rotor 3 Excessive liquid refrigerant in the compressor.

4 Compressor bearings are seized.

Outdoor unit power disconnect is open.

2 Unit circuit breaker or fuse(s) is open.

Yellow "Alert" 3 Unit contactor has failed to close.

Flash Code 5 Open Circuit 4 High pressure switch is open and requires manual reset.

5 Open circuit in compressor supply wiring or connections.

6 Unusually long compressor protector reset time due to extreme ambient temperature.

7 Compressor windings are dama0ed.

Yellow "Alert" _ Run capacitor has failed.

Flash Code 6 Open Start Circuit 2 Open circuit in compressor start wiring or connections.

Current only in run circuit 3 Compressor start windinq is damaqed.

Yellow "Alert"

Flash Code 7 Open Run Circuit 1 Open circuit in compressor start wiring or connections.

Current only in start circuit 2Compressor start windinq is damaqed.

Yellow "Alert"

Flash Code 8 Welded Contactor I Compressor contactor failed to open.

Compressor always runs 2 Thermostat demand siqnal not connected to module.

Yellow "Alert" Low Voltage 1 Control circuit transformer is overloaded

Flash Code 9 Control circuit < 17VAC 2Low line volta qe (contact utility if volta qe at disconnect is low.)

• Flash code number corresponds to a number of LED flashes, followed by a pause, and then repeated.

• TRIP and ALERT LEDs flashing at the same time indicates that the control circuit voltage is too low for operation.

• Reset ALERT flash code by removing 24VAC power from monitor. Last ALERT flash code will display for 1 minute after monitor is powered on.

The defrost system includes two components:

• a defrost thermostat

• a defrost control

Defrost Thermostat

The defrost thermostat is located on the liquid line be-

tween the check/expansion valve and the distributor.

When the defrost thermostat senses 42°F (5.5°C) or cool-

er, its contacts close and send a signal to the defrost con-

trol board to start the defrost timing. It also terminates de-

frost when the liquid line warms up to 70°F (21°C),

Defrost Control

The defrost control board includes the combined func-

tions of a time/temperature defrost control, defrost

relay, time delay, diagnostic LEDs, and a terminal strip

for field wiring connections, See figure 19.

The control provides automatic switching from normal

heating operation to defrost mode and back. During com-

pressor cycle (call for defrost), the control accumulates

compressor run times at 30, 60, or 90 minute field adjust-

able intervals. If the defrost thermostat is closed when the

selected compressor run time interval ends, the defrost

relay is energized and defrost begins,

Page 20

DefrostControlTimingPins

Eachtimingpinselectionprovidesa differentaccumu-

latedcompressorruntimeperiodduringonethermostat

runcycle.Thistimeperiodmustoccurbeforea defrost

cycleisinitiated.Thedefrostintervalcanbeadjustedto

30(T1),60(T2),or90(T3)minutes.Seefigure19,The

defrosttimingjumperis factory-installedto providea

90-minutedefrostinterval.Ifthetimingselectorjumperis

notinplace,thecontroldefaultstoa 90-minutedefrost

interval,Themaximumdefrostperiodis 14minutesand

cannotbeadjusted,

A TESToptionisprovidedfortroubleshooting,TheTEST

modemaybestartedanytimetheunitis intheheating

modeandthe defrostthermostatis closedor jump-

ered.IfthejumperisintheTESTpositionatpower-up,the

controlwillignorethetestpins,Whenthejumperisplaced

acrosstheTESTpinsfortwoseconds,thecontrolwillenter

thedefrostmode,Ifthejumperisremovedbeforeanaddi-

tional5-secondperiodhaselapsed(7secondstotal),the

unitwillremainindefrostmodeuntilthedefrostthermostat

opensor14minuteshavepassed.Ifthejumperisnotre-

moveduntil after the additional5-secondperiodhas

elapsed,thedefrostwillterminateandthetestoptionwill

notfunctionagainuntilthejumperis removedandreap-

plied,

CompressorDelay

The defrost board has a built-in function to reduce occasion-

al sounds that may occur while the unit is cycling in and out

of the defrost mode, The compressor will be cycled off for 30

seconds going in and out of the defrost mode.

NOTE -The 30 second off cycle is not functional when jump-

ering the TEST pins.

Time Delay

The timed-off delay is five minutes long. The delay helps

protect the compressor from short-cycling in case the power

to the unit is interrupted or a pressure switch opens, The

delay is bypassed by placing the timer select jumper across

the TEST pins for 0,5 seconds.

Pressure Switch Circuits

The defrost control includes two pressure switch circuits.

The high pressure switch ($4) is factory-connected to the

board's HI PS terminals. The board also includes LOPS ter-

minals to accommodate the addition of a field-provided low

pressure or loss of charge pressure switch, See figure 19.

This feature is available on all units,

During a single demand cycle, the defrost control will lock

out the unit after the fifth time that the circuit is interrupted

by any pressure switch that is wired to the control board. In

addition, the diagnostic LEDs will indicate a locked out

pressure switch after the fifth occurrence of an open pres-

sure switch, See table 9. The unit will remain locked out un-

til power is broken then remade to the control or until the

jumper is applied to the TEST pins for 0.5 seconds,

NOTE -The defrost control board ignores input from the

low pressure switch terminals during the TEST mode, dur-

ing the defrost cycle, during the 90-second start-up period,

and for the first 90 seconds each time the reversing valve

switches heat/cool modes. If the TEST pins are jumpered

and the 5-minute delay is being bypassed, the LOPS

terminal signal is not ignored during the 90-second

start-up period.

Ambient Thermistor & Service Light Connection

The defrost control board provides terminal connections

for the ambient thermistor and a service light. The thermis-

tor compensates for changes in ambient temperature

which might cause thermostat droop, The service light

thermostat provides a signal which activates the room ther-

mostat service light during periods of inefficient operation,

Diagnostic LEDs

The defrost board uses two LEDs for diagnostics, The

LEDs flash a specific sequence according to the diagnosis,

Table 9

Defrost Control Board Diagnostic

Mode

Normal operation /

power to board

Board failure or no

power

Board failure

High pressure switch

open

Low pressure switch open

Pressure switch lockout

Anti-short-cycle /

5-minute delay

LED 1

Synchronized

Flash with LED

Off

Flash

Alternating

Flash with

IFD2

LED

LED 2

Synchronized

Flash with LED

Off

Flash

Off

Alternating

Flash with

IFD1

Page 21

Pressure Switch

Wiring Connections

High

Pressure

Switch

(Factory-wired)

S _

[] HI PS

Optional

Pressure

Switch

(Field-provided

and installed --

jumper removed)

LO PS

High Pressure

Switch

Terminals

Optional

Pressure Switch

Terminals

(Remove factory-

installed jumper

to install

pressure switch.)

Defro_

Thermostat

Reversing

Valve

Defrost Control Board

U ===Wl

K2 RELAY] 0

FAN

HOT I

DEFROST K3 RELAY

INTERVAL

TIMING PINS

L0-PS

D,A NOST,°

LEDs

OTST

O-0UT o PS_

oDF

o 0 HOT

O o YI

Service

Light

Terminals

Ambient

Thermistor

Terminals

24V

Terminal

Strip

Figure

AWARNING

Maintenance and service must be performed by a quali-

fied installer or service agency. At the beginning of each

cooling or heating season, the system should be checked

as follows:

Outdoor Unit

1 - Clean and inspect outdoor coil (may be flushed with a

water hose). Ensure power is off before cleaning.

2 - Outdoor unit fan motor is prelubricated and sealed. No

further lubrication is needed.

3 - Visually inspect all connecting lines, joints and coils for

evidence of oil leaks.

4 - Check all wiring for loose connections.

5 - Check for correct voltage at unit (unit operating).

6 - Check amp-draw on outdoor fan motor.

7- Inspect drain holes in coil compartment base and

clean if necessary.

NOTE -If owner complains of insufficient cooling, the unit

should be gauged and refrigerant charge checked. Refer to

section on refrigerant charging in this instruction.

Indoor Coil

1 - Clean coil if necessary.

2 - Check connecting lines, joints and coil for evidence of

oil leaks.

3 - Check condensate line and clean if necessary.

Indoor Unit

1 - Clean or change filters,

2 - Lennox blower motors are prelubricated and permanent-

ly sealed, No more lubrication is needed.

3 - Adjust blower speed for cooling, Measure the pressure

drop over the coil to determine the correct blower CFM

Refer to the unit information service manual for pressure

drop tables and procedure,

4 - Belt Drive Blowers - Check belt for wear and proper

tension,

5 - Check all wiring for loose connections,

6 - Check for correct voltage at unit,

Page 22

7- Checkamp-drawonblowermotor.

RefertotheEngineeringHandbookforoptionalaccesso-

riesthatmayapplytothisunit,Thefollowingmayormay

notapply:

• Lossof ChargeKit

• HighPressureSwitcKit

• CompressorMonitor

• CompressorCrankcaseHeater

• HailGuards

• MountingBases

• TimedOffControl

• Stand-offKit

• SoundCover

• LowAmbientKit

• MonitorKit

Inordertoensurepeakperformance,yoursystemmustbe

properlymaintained.Cloggedfiltersandblockedairflow

preventyourunitfromoperatingat itsmostefficientlevel,

AskyourLennoxdealerto showyouwhereyourindoor

unit'sfilteris located.It will beeitherat theindoorunit

(installedinternalorexternalto thecabinet)orbehindare-

turnairgrilleinthewallorceiling.Checkthefiltermonthly

andcleanorreplaceitasneeded,

Disposablefiltersshouldbereplacedwitha filterof the

sametypeandsize,Ifyouareunsureaboutthefilteryou

needforyoursystem,callyourLennoxdealerfor assis-

tance.

AIMPORTANT

Many indoor units are equipped with reusable foam filters.

These filters can be cleaned with a mild soap and water

solution, Rinse the filter thoroughly and let it dry completely

before it is returned to the unit or grille,

The filter and all access panels must be in place any

time the unit is in operation.

Your system may be equipped with an electronic air clean-

er which will provide respiratory relief by removing up to 90

percent of all airborne particles which pass through it. If it

is, ask your dealer to instruct you on its maintenance,

Your indoor evaporator coil is equipped with a drain pan to

collect condensate formed as your system removes hu-

midity from the inside air. Have your dealer show you where

the main condensate drain (and auxiliary drain, if applica-

ble) runs and how to check the drain for any obstruction,

It is also very important to provide unrestricted airflow to the

outdoor unit, Leaves, trash or shrubs crowding the unit

cause the outdoor unit to work harder and use more ener-

gy. Keep shrubbery trimmed away from the unit and period-

ically check for debris which may have collected around

the unit,

Heat Pump Operation

Your new Lennox heat pump has several characteristics

that you should be aware of:

Your heat pump satisfies heating demand by delivering

large amounts of warm air into the living space. This is quite

different from gas- or oil-fired furnaces or an electric fur-

nace which deliver lower volumes of considerably hotter air

to heat the space,

Do not be alarmed if you notice frost on the outdoor coil in

the winter months. Frost develops on the outdoor coil dur-

ing the heating cycle when temperatures are below 45°F

(7°C). An electronic control activates a defrost cycle lasting

5 to 15 minutes at preset intervals to clear the outdoor coil

of the frost. During the defrost cycle, you may notice steam

rising from the outdoor unit, This is a normal occurrence.

The thermostat may engage auxiliary heat during the de-

frost cycle to satisfy a heating demand; however, the unit

will return to normal operation at the conclusion of the de-

frost cycle.

Your Lennox HPXB15 heat pump is equipped with a com-

pressor crankcase heater which protects the compressor

from refrigerant slugging during cold weather operation. If

power to your unit has been interrupted for several hours

or more, set the room thermostat selector to the "Emergen-

cy Heat" setting to obtain temporary heat without the risk

of serious equipment damage, In this operating mode, all

heating demand will be satisfied by auxiliary heat. Com-

pressor operation is locked out during Emergency Heat op-

eration. After a six-hour compressor crankcase heater

warm-up period, the thermostat can be switched to the

"Heat" setting and normal operation will resume.

Thermostat Operation

Though your thermostat may vary somewhat from the de-

scription below, its operation will be similar,

Temperature Setting Levers

Most heat pump thermostats have two temperature selec-

tor levers: one for heating and one for cooling, Set the lev-

ers or dials to the desired temperature setpoints for both

heating and cooling. Avoid frequent temperature adjust-

ment; turning the unit off and back on before pressures

equalize puts stress on the unit compressor.

Fan Switch

In AUTO or INT (intermittent) mode, the blower operates

only when the thermostat calls for heating or cooling. This

mode is generally preferred when humidity control is a

priority. The ON or CONT mode provides continuous in-

door blower operation, regardless of whether the compres-

sor or auxiliary heat are operating, This mode is required

when constant air circulation or filtering is desired.

Page 23

System Switch

Set the system switch for heating, cooling or auto opera-

tion, The auto mode allows the heat pump to automatically

switch from heating mode to cooling mode to maintain pre-

determined comfort settings, Many heat pump thermostats

are also equipped with an emergency heat mode which

locks out heat pump operation and provides temporary

heat supplied by the auxiliary heat,

Indicating Light

Most heat pump thermostats have an amber light which in-

dicates when the heat pump is operating in the emergency

heat mode.

Temperature Indicator

The temperature indicator displays the actual room tem-

perature,

Programmable Thermostats

Your Lennox system may be controlled by a programmable

thermostat. These thermostats provide the added feature

of programmable time-of-day setpoints for both heating

and cooling, Refer to the user's information manual pro-

vided with your particular thermostat for operation details.

Preservice Check

If your system fails to operate, check the following before

calling for service:

• Check to see that all electrical disconnect switches

are ON,

• Make sure the room thermostat temperature selector

is properly set,

• Make sure the room thermostat system switch is prop-

erly set.

• Replace any blown fuses, or reset circuit breakers.

• Make sure unit access panels are in place.

• Make sure air filter is clean,

• Locate unit model number and have it handy before

calling,

Start-up and Performance Check List

Job Name Job No, Date

Job Location City State

Installer City State

Unit Model No, Serial No. Service Technician

Nameplate Voltage

Rated Load Ampacity

Maximum Fuse or Circuit Breaker

Electrical Connections Tight? []

Indoor Blower RPM

Cooling

Liquid Line Pressure

Heating

Liquid Line Pressure

Refrigerant Lines: Leak Checked? []

Service Valves Fully Opened? []

Sequence of Operation

Heating Correct []

Compressor

Indoor Filter Clean? []

S.R Drop Over Indoor (Dry)

Vapor Pressure

Outdoor Fan

Supply Voltage (Unit Off) __

-- Outdoor Coil Entering Air Temp.

Vapor Pressure

Properly Insulated? []

Service Valve Caps Tight? []

Refrigerant Charge Checked? []

Outdoor Fan Checked? []

Cooling Correct []

Voltage With Compressor Operating --

Thermostat

Calibrated? [] Properly Set? [] Level? []

Page 24

LENNOX Air Conditioner/heat Pump(outside Unit) Manual L0806498

Navigation menu

Versions of this User Manual:

Views

Navigation