York Eco R 407C Users Manual Form 100.50 EG1(201), Eco2 Packaged Rooftop Air Conditioning Units, Engineering Guide

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FORM 100.50-EG1 (201)

Packaged Rooftop
Air Conditioning Units

00406VIP

R-407C OPTIMIZED
50 THROUGH 65 TONS

TABLE OF CONTENTS

PAGE

Nomenclature ......................................................................................................... 3
Introduction ............................................................................................................. 4
Physical Data .......................................................................................................... 7
Application Data ...................................................................................................... 9
Cooling Performance Data .................................................................................... 12
Fan Performance .................................................................................................. 20
Electrical Data ....................................................................................................... 24
Controls ................................................................................................................ 26
Power Wiring ........................................................................................................ 31
Field Control Wiring .............................................................................................. 34
General Arrangement Drawing ............................................................................. 35
Curb Layout Drawing ............................................................................................ 37
Mechanical Specifications ..................................................................................... 38

TABLES

2

1

Physical Data ............................................................................................. 7

2

Cooling Performance Data – 50 Ton Model .............................................. 12

3

Cooling Performance Data – 55 Ton Model .............................................. 14

4

Cooling Performance Data – 60 Ton Model .............................................. 16

5

Cooling Performance Data – 65 Ton Model .............................................. 18

6

50 Through 65 Ton Supply Fan Data ........................................................ 20

7

50 Through 65 Ton Exhaust Fan Data ...................................................... 21

8

Component Static Pressure Drops ........................................................... 22

9

Compressors ........................................................................................... 24

10

Supply and Exhaust Fan Motor Electrical Data ........................................ 25

11

Condenser Fan Motors ............................................................................ 25

12

Controls and Convenience Outlet ............................................................. 25

YORK INTERNATIONAL

FORM 100.50-EG1

PAGE

FIGURES
1

Packaged Rooftop Air Conditioning Unit .................................................. 4

2

Single-Point Power Supply Wiring .......................................................... 31

3

Single-Point Power Supply Wiring with Non-Fused Disconnect ............. 32

4

Dual-Point Power Supply Wiring ............................................................ 33

5

Field Control Wiring ............................................................................... 34

6

General Arrangement Drawing – Bottom Return, Bottom Supply ........... 35

7

General Arrangement Drawing – Rear Return, Left or Right Supply ...... 36

8

Curb Layout Drawing .............................................................................. 37

NOMENCLATURE

BASIC MODEL NUMBER
1 2 3 4

5 6 7

8 9

BASE PRODUCT TYPE

NOMINAL CAPACITY

APPLICATION REFRIGERANT

Y

0
0
0
0

P
A

: YORK
: Packaged
Rooftop
: Air-Cooled

5
5
6
6

0 : 50-ton
5 : 55-ton
0 : 60-ton
5 : 65-ton

10
B : R-407C

11 12

13 14

15 16

VOLTAGE

DUCT LOCATIONS

DESIGN SPECIAL

1
2
4
5

L: Scroll

C

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7 : 200 / 3 / 60
8 : 230 / 3 / 60
6 : 460 / 3 / 60
8 : 575 / 3 / 60

B
L
R

: Bottom Supply
: Left Supply
: Right Supply
B : Bottom Return
F : Front Return
S : Side Return

A

: Rev. Level A
S : Std. Product
X : Special

: Cooling Only
C : Constant Volume
V : VAV, VFD
B : VAV, VFD w/ Manual Bypass

3

Introduction

00406VIP

FIG. 1 – PACKAGED ROOFTOP AIR CONDITIONING UNIT

FEATURES/BENEFITS
Ecological and Economical Design
• First packaged RTU with 407C optimized design
• Cooling and Heating – Superior operating performance provides lower operating costs. Smaller
steps of cooling capacity provide tighter control of
building environment and occupant comfort while
optimizing energy efficiency.
• Indoor Air Quality (IAQ) – Outside air economizers provide energy savings in free cooling mode,
and can provide a healthier and more comfortable
building environment by introducing fresh outside air
into the building as needed. Indoor Air Quality (IAQ)
requirements for building ventilation and comfort are
controlled through the microprocessor control panel.
Optional air flow measurement provides an accurate means of tracking air quality and alerting the
occupants or building owner to unhealthy situations.
• High-Efficiency Motors – High-efficiency motors are
available for optimum energy efficiency. All motors
used on the eco2 packaged rooftop air conditioner
meet U.S. EPACT 1992 minimum requirements.
Indoor Air Quality (IAQ)
• Double-sloped stainless steel drain pan – This
double-sloped inclined stainless steel drain pan facilitates removal of evaporator condensate. Sloped

4

in two directions conforming to ASHRAE 62n, this
drain pan swiftly minimizes any condensate within
the unit. Best of all, the drain pan is accessible for
periodic cleaning required by IAQ standards.
• Smart ventilation – YORK maintains the leadership role in IAQ products with adaptive ventilation
control. The OptiLogicTM controls provide continuous monitoring of air quality and take action by opening the outside air dampers, bringing in the right
amount of fresh air before air impurities reach uncomfortable or even dangerous levels.
• Air flow measurement – Precise measurement
of ventilation air flow is possible using an air flow
measurement station which can be installed in the
economizer section. Proper ventilation air flow is
required to ensure sufficient fresh air is in the building. A myriad of air flow measurement options are
available from minimum air flow to high-accuracy
full air flow capabilities. The complete system is
designed as an integrated component of the
OptiLogicTM control system to ensure optimum system performance.
• Double-wall construction – Rigid double-wall
construction throughout provides ease of cleaning and protects against insulation fiber entrainment in the breathable air. Double-wall construction also helps improve the acoustical characteristics of the air handling unit.
YORK INTERNATIONAL

FORM 100.50-EG1

• Enhanced filtration – The Eco2 unit gives designers the flexibility to meet various IAQ requirements
with a full range of rigid and throwaway filters at
various efficiency levels.
Reliable Scroll Compressor Technology
Reliable, efficient, trouble-free operation is the true measure of a packaged rooftop’s value. That’s why YORK
Eco2 Packaged Rooftop Air Conditioners use established scroll-compressor technology to deliver dependable, economical performance in a wide range of applications. With the Eco2 Packaged Rooftop, you get the
latest generation of compressor enhancements added
to the scroll’s inherent strengths. The simplicity of a
hermetic scroll compressor allows the use of fewer
moving parts to minimize breakdown. YORK also employs the latest sealing technology to avoid metal-tometal contact. Axial sealing is accomplished with floating tip seals, while radial sealing utilizes a microcushion
of oil. The result: a maintenance-free compressor providing minimum wear and maximum runtime.
A scroll compressor operates with two scroll members—
a fixed scroll and an identical orbiting scroll turned 180
degrees, like two hands curled and interlocked together.
As the orbiting scroll oscillates against the fixed scroll,
it traps and compresses suction gas inside involute
pockets. As the orbiting scroll moves, the gas is compressed into the central area, where it is discharged as
compressed gas. High efficiency is achieved through a
precisely controlled orbit and the use of advanced scroll
geometry. There is no wasted motion. All rotating parts
are statically and dynamically balanced to ensure optimal performance over the long haul.
Balanced components and precision machining also
ensure that smooth compression occurs in all involute
pockets simultaneously. When compression forces are
equally distributed over the entire scroll surface, equal
forces in opposing directions cancel one another, minimizing any imbalance. Consequently, compression is
smooth, continuous, and quiet. Vibration isolators on
each compressor handle normal vibration. For extra
quiet operation, acoustic sound blankets for each compressor are available as options.

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Serviceability
• OptiLogicTM – fully-integrated factory-packaged
controls are standard on every unit and include a
display unit with a 4x20 character LCD display.
OptiLogicTM continually monitors all control setpoints
and configurations. If a unit or control component,
or sensor fails, the controller notifies the user of a
problem. If desired, YORK service can provide remote monitoring and automatically schedule a service technician to make the repair and maintain your
comfort.
• Access doors – full-sized access doors provide
easy access into the unit for routine maintenance
and inspection.
• Suction & discharge service valves – oversized
service valves to provide isolation and quick reclamation and charging of system refrigerant are available to minimize downtime and simplify the service
and repair task.
• VFD Fan Motor Control with Manual Bypass –
Optional manual VFD bypass reduces time required
for troubleshooting, commissioning and system
balancing.
• Convenience Outlet – for maintenance tasks requiring power tools, an optional 110V GFCI power
supply can power lights, drills or any other power
hand tool needed.
• Filter Maintenance Alarm – An optional filter maintenance alarm indicates when a filter becomes dirty
and requires replacement or cleaning.
Install with Ease and Safety
• Factory run-tested – Each unit is subjected to a
series of quality assurance checks as well as an
automated quality control process before being runtested. Fans and drives are balanced at the factory
during testing. The factory run-test ensures safe,
proper operation when the unit is installed and reduces installation and commissioning time.
• Single-point power connection – Single-point
power connection reduces installation time by providing a single point for incoming power, including

5

Introduction
the optional convenience outlet. All incoming power
is connected in one location, reducing the cost of
field-supplied and installed power wiring.
• Factory-mounted and wired controls – All control points within the unit are factory-installed, wired
and tested. The OptiLogicTM controls can communicate with BACNet IP.
• Non-fused disconnect – A factory-installed nonfused disconnect switch simplifies unit installation
and serviceability by reducing installed labor costs.
The disconnect switch is interlocked with the power
cabinet ensuring that all power to the unit has been
disconnected before servicing.
Design Flexibility
• Low Ambient Operation – Head-pressure control
is accomplished via a VFD motor controller rather
than an inefficient and noisy condenser fan damper.
By varying the speed of the condenser fan, better
control and quieter operation is obtained during the
colder months. Low ambient controls are available

6

on all systems offering higher rooftop cooling capacity than competitive units.
• Hot Gas Bypass – Optional on constant volume units,
hot gas bypass reduces the cycling of compressors
which helps prolong the life of the equipment.
• Supply Air Openings – Side supply connections
are available on select configurations, offering more
flexibility for duct layout and improving sound transmission characteristics.
• Compressor Sound Blankets – For applications
in sound-sensitive areas, compressor sound blankets are available to reduce sound emitted from
the rooftop unit.
• Fan Spring Isolators – One-inch spring isolation
is used to prevent vibration transmission from the
rooftop unit’s supply fan to the building. Two-inch
spring isolation is also available.
• Harsh Environments – A variety of coil coating and
materials are available as well as hail guards to protect coils from weather damage. Seismic and hurricane duty curbs and fan restraints are available.

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FORM 100.50-EG1

Physical Data
TABLE 1 – PHYSICAL DATA
MODEL SIZE
GENERAL DATA
Length (Inches)
Width (Inches)
Height (Inches)
Operating Weights (Lbs.) (base unit, no options)
Cooling Only (Rigging & Refrigerant)
Rigging Weights (Lbs.) (base unit, no options)
Cooling Only
Option Weights (Lbs.)
Power Exhaust (Blower, motor, fan skid & mod damper)
Power Exhaust (Blower, motor, fan skid, VFD & baro damper)
100% AMS (Measurement Station & Mounting)
25/75% AMS (Measurement Station & Mounting)
Min. AMS (Measurement Station & Mounting)
Barometric only
Condenser Hail Guard
Copper Condenser Coils
Copper Evaporator Coils
Roof Curb Weights (Lbs.)
14" Full Perimeter Roof Curb
14" Open Condenser Roof Curb
Compressor Data
Quantity / Size (Nominal Tons )
Type
Capacity Steps (%)
Supply Fan and Drive
Quantity
Type
Size
Motor Size Range (min. to max. HP)
Air Flow Range (min. to max. cfm)
Static Pressure Range (min. to max. ESP)
Exhaust Fan
Quantity
Type
Size
Motor Size Range (min. to max. HP)
Air Flow Range (min. to max. cfm)
Static Pressure Range (min. to max. ESP)
Evaporator Coil
Size (square feet)
Number of rows/fins per inch
Tube Diameter/Surface
Condenser Coil (Aluminum Fins)
Size (square feet)
Number of rows/fins per inch
Tube Diameter
Condenser Coil (Copper Fins – Opt)
Size (square feet)
Number of rows/fins per inch
Tube Diameter

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50

55

60

65

336
92
82

336
92
82

336
92
82

336
92
82

8,080

8,290

8,530

8,740

8,010

8,210

8,440

8,640

647
654
110
130
40
36
32
617
262

647
654
110
130
40
36
32
617
320

647
654
110
130
40
36
32
793
400

647
654
110
130
40
36
32
793
500

787
555

787
555

787
555

787
555

4/13
4/13
4/15
4/15
Scroll
Scroll
Scroll
Scroll
25, 50, 75, 100 25, 50, 75, 100 25, 50, 75, 100 25, 50, 75, 100
1
FC
25-22
7.5-40
10000-22500
0-4"

1
FC
25-22
7.5-40
12000-24000
0-4"

1
FC
25-22
7.5-40
14000-27000
0-4"

1
FC
25-22
7.5-40
14000-27000
0-4"

2
FC
15-15
5-20
0-20000
0-1"

2
FC
15-15
5-20
0-20000
0-1"

2
FC
15-15
5-20
0-20000
0-1"

2
FC
15-15
5-20
0-20000
0-1"

48.8
3/8
1/2"/enhanced

48.8
4/8
1/2"/enhanced

48.8
4/12
1/2"/enhanced

48.8
5/10
1/2"/enhanced

121.3
3/14
3/8"

121.3
3/14
3/8"

121.3
3/18
3/8"

121.3
3/18
3/8"

121.3
3/14
3/8"

121.3
3/14
3/8"

121.3
3/18
3/8"

121.3
3/18
3/8"

7

Physical Data (continued)
TABLE 1 – PHYSICAL DATA (Cont’d)
MODEL SIZE
GENERAL DATA
Condenser Fans
Quantity
Type
Diameter (inches)
Filters – 2" throwaway
Quantity
Size (length x width) (in.)
Total Filter Face Area (square feet)
Filters – 2" cleanable
Quantity
Size (length x width) (in.)
Total Filter Face Area (square feet)
Filters – 2" pleated (30% efficient)
Quantity
Size (length x width) (in.)
Total Filter Face Area (square feet)
Filters – 12" rigid 65%, 2" 30% prefilter
Quantity
Size (length x width) (in.)
Total Filter Face Area (square feet)
Filters – 12" rigid 95%, 2" 30% prefilter
Quantity
Size (length x width) (in.)
Total Filter Face Area (square feet)
Filters – 2" carbon (30% efficient)
Quantity
Size (length x width) (in.)
Total Filter Face Area (square feet)
Refrigerant
Minimum OA Temp. for Mech. Clg. (°F)
Low Ambient Option Min. OA Temp. (°F)

8

50

55

60

65

4
Prop.
36

4
Prop.
36

4
Prop.
36

4
Prop.
36

8
12
25x16 25x20
63.9

8
12
25x16 25x20
63.9

8
12
25x16 25x20
63.9

8
12
25x16 25x20
63.9

8
12
25x16 25x20
63.9

8
12
25x16 25x20
63.9

8
12
25x16 25x20
63.9

8
12
25x16 25x20
63.9

8
12
25x16 25x20
63.9

8
12
25x16 25x20
63.9

8
12
25x16 25x20
63.9

8
12
25x16 25x20
63.9

1

4

9

1

4

9

1

4

9

1

4

9

16x20 25x16 25x20 16x20 25x16 25x20 16x20 25x16 25x20 16x20 25x16 25x20

44.6
1

4

44.6
9

1

4

44.6
9

1

4

44.6
9

1

4

9

16x20 25x16 25x20 16x20 25x16 25x20 16x20 25x16 25x20 16x20 25x16 25x200

44.6

44.6

44.6

44.6

8
12
25x16 25x20
63.9
HFC-407C
45
0

8
12
25x16 25x20
63.9
HFC-407C
45
0

8
12
25x16 25x20
63.9
HFC-407C
45
0

8
12
25x16 25x20
63.9
HFC-407C
45
0

YORK INTERNATIONAL

FORM 100.50-EG1

Application Data
LOCATION
Of the many factors that can affect the acoustical characteristics of a rooftop installation, one of the most important is the unit location. Ideally, the rooftop unit should
be installed away from sound-sensitive areas, such as
conference rooms, auditoriums and executive offices.
Possible locations could be above storage areas, hallways, mechanical or utility rooms, or bathrooms.
2

The eco air conditioning units are designed for outdoor installation. When selecting a site for installation,
be guided by the following conditions:
• Unit must be installed on a level surface.
• For the outdoor location of the unit, select a place
having a minimum sun exposure and an adequate
supply of fresh air for the condenser.
• Also avoid locations beneath windows or between
structures.
• Optional condenser coil protection should be used
for seashore locations or other harsh environments.
• The unit should be installed on a roof that is structurally strong enough to support the weight of the
unit with a minimum of deflection. Extreme caution
should be taken when the unit is mounted on a wood
structured roof. It is recommended that the unit(s)
be installed not more than 15 feet from a main support beam to provide proper structural support and
to minimize the transmission of sound and vibration. Ideally, the center of gravity should be located
over a structural support or building column.
• Location of unit(s) should also be away from building flue stacks or exhaust ventilators to prevent possible reintroduction of contaminated air through the
outside air intakes.

Spreader bars must be used to prevent damage to the
unit casing. All lifting lugs must be used when lifting the
rooftop unit.
Care must be taken to keep the unit in the upright position during rigging and to prevent damage to the watertight seams in the unit casing. Avoid unnecessary jarring or rough handling.
Ground Level Locations
It is important that the units be installed on a substantial base that will not settle, causing strain on the refrigerant lines and sheet metal and resulting in possible
leaks. A one-piece concrete slab with footers extended
below the frost line is highly recommended. Additionally, the slab should not be tied to the main building
foundation as noises may be transmitted into the building structure.
For ground level installations, precautions should be
taken to protect the unit from tampering by, or injury to,
unauthorized persons. Erecting a fence around the unit
is another common practice.
ECONOMIZER
The economizer section is used for ventilation of the
conditioned space to maintain indoor air quality, and
also to reduce energy consumption by using outdoor
air cooling in lieu of mechanical cooling. If outdoor air
is appropriate for cooling, but not sufficient for the cooling demand, mechanical cooling will stage on as necessary until the cooling load is met.
Comparative enthalpy operation is the most accurate and
efficient means of economizer operation. The OptiLogicTM
control monitors the return and outside air energy content, and selects the lower of the two for operation.

• Be sure the supporting structures will not obstruct
the duct, gas or wiring connections.

VAV SUPPLY AIR PRESSURE CONTROL

• Proper service clearance space of 6-feet around
the perimeter of the unit and 12-feet to any adjacent units is required to eliminate cross contamination of exhaust and outdoor air, and for maintenance tasks such as coil pull and cleaning. No obstructions should be above the condensing unit
section.

Traditional packaged rooftop systems use inlet guide
vanes (IGVs) for duct static pressure control. These control supply duct pressure by modulating dampers (introducing losses and inefficiencies) on the intlet of the fan,
open and closed. Variable frequency drives (VFDs) offer superior fan speed control and quieter, energy efficient operation.

RIGGING
Proper rigging and handling of the equipment is mandatory during unloading and setting it into position to
retain warranty status.
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IGV inefficiency can be compared to the operation of a
car. Modulating air flow with an IGV is like pressing on
the gas to drive the car, but modulating the speed of the
car by simultaneously pressing on the brake. VFD modulation is speed modulation by using just the gas pedal.

9

Application Data (continued)
For VAV applications, the YORK eco2 unit uses a VFD
to modulate fan speed and maintain a constant duct
static pressure. VFDs offer superior control over the
operation of the unit at part load, and offer the additional benefits of quieter and more efficient operation
when compared to IGV.
HARSH ENVIRONMENTS – CONDENSER AND
EVAPORATOR COIL PROTECTION
For harsh environmental conditions such as seashore
applications, YORK offers three types of coil protection: copper fin material, black fin and Technicoat coatings. YORK recommends that for corrosive environments that copper fins be used to protect the evaporator and/or condenser coils. In areas where chemicals
that can corrode copper are present, such as ammonia, YORK recommends that the black fin or Technicoat
coating be used for maximum protection.
Copper Fin Condenser Coil
Copper fins can be used instead of aluminum for additional corrosion protection, however it is not suitable
for areas that are subject to acid rain or exposed to
ammonia.
Pre-Coated Condenser Fins
Black fin coating (yellow fin for evaporator fins) is precoated application epoxy on aluminum fin stock to guard
from corrosive agents and insulate against galvanic potential. It is used for mild seashore or industrial locations. This can provide corrosion resistance comparable
to copper fin coils in typical seashore locations.
Post-Coated Condenser Fins
Technicoat (a post-coated application of epoxy) can be
used for seashore and other corrosive applications with
the exception of strong alkalides, oxidizers, wet bromide, chlorine and fluorine in concentrations greater
than 100 ppm.
Any of the above suitable options should be selected
based on the particular project design parameters and
related environmental factors. The application should
be further reviewed and approved by the consulting engineer or owner based on their knowledge of the job
site conditions.

10

BUILDING EXHAUST SYSTEMS
Building exhaust systems are often necessary when
economizers are used to bring in outdoor air. Without
proper building exhaust, the building may become overpressurized. The exhaust system maintains the proper
building pressure by expelling the appropriate amount
of air from the building. Exhaust systems are typically
designed to exhaust approximately 10% less air than
what is entering the building. This provides a slight positive pressure on the building.
100% modulating exhaust with building static
pressure sensing and control
The 100% exhaust system can be configured with either control actuated dampers or VFDs for modulating
control. The unit controller monitors the building pressure using a differential pressure transducer and maintains the required building static pressure by modulating the exhaust control. If the building has other means
of exhaust or building pressure is not important, on/off
or barometric control may be used.
100% modulating exhaust with fan on/off control
The 100% exhaust system can be configured for on/off
operation eliminating the expense of the damper actuators or VFDs. This exhaust system can be controlled
by either the outside air damper position, or a building
static pressure sensor.
Barometric exhaust
Barometric exhaust can be used when smaller amounts
of air at low static pressure variations within the building or other means of building exhaust are employed.
Barometric exhaust is commonly used where there are
only small fluctuations in building pressure or where
building static pressure control is not necessary.
ROOF CURB
Optional 14-inch full-perimeter or open condenser roof
curbs can be provided if necessary for mounting to
the building roof. These curbs come disassembled and
require installation in the field. For bottom supply and
return duct openings, the curbs have matching connections to ease installation. A pipe chase that
matches the rooftop unit is also included in the curb
footprint for through-the-curb utility connections.

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FORM 100.50-EG1

The curb should be located according to the location
recommendations above, and properly sealed to prevent moisture and air leakage into and out of the duct
system. Flexible collars should be used when connecting the duct work to prevent unit noise transmission
and vibration into the building.
Duct work should be supported independently of the
unit.
ACOUSTICAL CONSIDERATIONS
The eco2 unit is designed for lower sound levels than
competitive units by using flexible fan connections, fan
spring isolators, double-wall construction, and lower
speed and horsepower fans. For VAV applications,
VFDs are used instead of inlet guide vanes. Additional
sound attenuation can be obtained using compressor
sound blankets and field-supplied sound attenuators
when necessary.
Even with these equipment design features, the acoustical characteristics of the entire installation must never
be overlooked. Additional steps for the acoustical characteristics of a rooftop installation should be addressed
during the design phase of a project to avoid costly alterations after the installation of the equipment. During
the design phase of a project, the designing engineer
should consider, at a minimum, the impact of the equipment location, rooftop installation, building structure,
and duct work.
SELECTION PROCEDURE
Given:
Required total cooling capacity of 600 mbh and sensible cooling capacity of 450 mbh with evaporator entering air conditions of 83°F dry bulb and 67°F wet bulb.
Design ambient temperature is 95°F dry bulb. Supply
air requirements are 17500 cfm of air at 2.25 IWG external static pressure. Power supply is 460V/3ph/60Hz

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and the unit requires a modulating economizer, 2-inch
pleated filters, bottom supply and bottom return air openings and is constant volume.
Select Unit:
1. Determine the internal static pressure drop of the
cabinet by referencing Table 8.
Wet evaporator coil
0.54
Bottom supply opening
0.14
Bottom return opening
0.13
2-inch pleated filters
0.10
Economizer openings
0.24
Modulating economizer dampers
0.31
Total 1.46 IWG
2. Determine the total static pressure by adding the
internal to the external static pressure.
TSP = 1.46 IWG + 2.25 IWG
= 3.71 IWG total static pressure
3. Determine the BHP of the supply fan from Table 6
using the supply air flow and total static pressure.
From the table, we interpolate to get 15.1 BHP. Assuming a drive loss of 3% and a motor efficiency of
90%, we can calculate the heat rejection of the supply fan motor as:
(2545 x 15.1)/(0.90 x (1-0.03)) = 44.0 mbh

Required Cooling Capacities:
Total = 600 + 44.0 = 644 mbh
Sensible = 450 + 44.0 = 494 mbh
4. Required total and sensible capacities are 644 mbh
and 494 mbh, respectively. Using the Cooling Performance Data starting with Tables 2, locate the
table with the correct ambient air temperature. Next,
trace the 83°F entering air dry bulb temperature to
match the 17,500 cfm and 67°F entering wet bulb
temperature condition. The resulting conditions are,
from the table, 645 mbh total cooling capacity and
497 mbh sensible cooling capacity. Thus, a 50-ton
unit is selected.

11

Cooling Performance Data – 50 Ton Model
TABLE 2 – COOLING PERFORMANCE DATA – 50 TON MODEL

85° AIR ON CONDENSER COIL
CAPACITY (MBH) AT ENTERING DRY BULB (°F)
CFM

10000

14000

17500

20000

22500

ENTERING

90

86

83

80

77

74

WB (°F)

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

72

700

477

700

431

695

387

692

353

691

311

—

—

67

653

548

646

500

635

454

637

416

632

377

626

343

62

640

640

608

608

590

583

582

562

569

514

574

455

72

711

500

708

445

705

399

701

360

699

316

—

—

67

665

581

656

523

647

474

647

431

643

388

637

349

62

654

654

625

625

606

606

594

547

583

498

585

439

72

729

536

721

467

719

418

715

370

712

324

—

—

67

684

634

672

558

666

505

663

454

660

406

653

359

62

680

680

652

652

632

625

612

550

606

497

603

438

72

749

576

736

492

736

439

732

382

726

333

—

—

67

705

695

689

597

686

540

680

479

679

425

672

370

62

710

710

682

682

661

661

633

582

631

523

622

467

72

758

595

742

504

743

449

739

388

732

338

—

—

67

715

715

697

616

696

557

689

492

688

435

680

376

62

715

715

696

610

674

549

643

486

643

429

631

370

* Rated performance is at sea level. Cooling capacities are gross cooling capacity.

95° AIR ON CONDENSER COIL
CAPACITY (MBH) AT ENTERING DRY BULB (°F)
CFM

10000

14000

17500

20000

22500

ENTERING

90

86

83

80

77

74

WB (°F)

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

72

673

468

673

416

669

375

667

340

664

301

—

SHC
—

67

628

536

630

494

615

445

616

404

609

383

605

331

62

618

618

590

590

569

513

571

481

562

435

562

390

72

684

491

682

432

678

388

676

348

673

306

—

—

67

642

569

638

515

627

465

625

419

619

382

615

338

62

635

635

607

607

586

541

580

500

572

453

571

407

72

701

526

696

458

693

407

690

360

686

315

—

—

67

665

625

651

547

645

497

640

443

635

382

630

348

62

661

661

634

634

612

587

594

531

588

481

586

433

72

720

565

712

486

709

429

705

373

701

325

—

—

67

691

691

665

582

665

532

656

470

653

382

647

360

62

691

691

663

663

641

641

609

565

606

511

602

462

72

729

584

720

500

717

439

712

380

708

329

—

—

67

703

703

672

599

674

549

664

483

661

382

655

366

62

704

704

675

658

655

629

617

556

614

488

610

447

* Rated performance is at sea level. Cooling capacities are gross cooling capacity.

12

YORK INTERNATIONAL

FORM 100.50-EG1

TABLE 2 – COOLING PERFORMANCE DATA – 50 TON MODEL (CONT’D)

105° AIR ON CONDENSER COIL
CAPACITY (MBH) AT ENTERING DRY BULB (°F)
CFM

10000

14000

17500

20000

22500

ENTERING

90

86

83

80

77

74

WB (°F)

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

72

649

464

650

409

645

365

644

330

644

290

—

SHC
—

67

590

513

596

478

589

434

591

390

593

354

589

318

62

597

597

573

573

536

498

549

460

544

429

542

384

72

658

483

658

424

653

378

651

338

650

295

—

—

67

609

550

608

501

600

454

600

406

601

366

597

326

62

614

614

589

589

556

527

557

483

553

446

550

397

72

673

512

670

447

667

397

663

350

661

303

—

—

67

638

607

625

537

618

485

615

432

613

384

609

337

62

641

641

614

614

587

571

570

520

567

472

563

419

72

689

545

684

472

682

419

677

364

672

311

—

—

67

670

670

645

577

638

520

631

461

626

404

623

350

62

670

670

642

642

621

621

584

561

582

500

576

443

72

696

560

690

485

690

430

683

371

678

315

—

—

67

686

695

654

596

647

537

639

475

632

414

629

356

62

684

684

655

655

637

644

591

580

590

514

583

455

* Rated performance is at sea level. Cooling capacities are gross cooling capacity.

115° AIR ON CONDENSER COIL
CAPACITY (MBH) AT ENTERING DRY BULB (°F)
CFM

10000

14000

17500

20000

22500

ENTERING

90

86

83

80

77

74

WB (°F)

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

72

563

368

562

318

567

286

558

258

563

233

—

SHC
—

67

494

424

524

387

514

349

515

313

514

281

518

254

62

498

498

501

501

442

424

458

349

467

343

467

306

72

592

432

588

370

589

325

585

286

583

246

—

—

67

548

509

545

449

541

406

539

359

536

317

537

276

62

550

550

533

533

498

488

494

434

491

395

489

349

72

608

465

603

397

600

346

600

300

594

253

—

—

67

577

555

557

481

555

435

552

383

548

336

547

288

62

578

578

550

550

527

522

513

478

504

422

500

371

72

625

503

618

427

613

368

616

316

606

261

—

—

67

609

609

570

517

571

468

566

410

562

357

558

301

62

609

609

568

568

560

560

534

528

518

452

513

396

72

633

520

626

441

619

379

623

324

611

265

—

—

67

624

624

576

534

579

484

572

423

568

367

563

307

62

624

624

577

577

575

578

544

548

525

467

520

408

* Rated performance is at sea level. Cooling capacities are gross cooling capacity.

YORK INTERNATIONAL

13

Cooling Performance Data – 55 Ton Model
TABLE 3 – COOLING PERFORMANCE DATA – 55 TON MODEL

85° AIR ON CONDENSER COIL
CAPACITY (MBH) AT ENTERING DRY BULB (°F)
CFM

12000

16000

19250

22000

24000

ENTERING

90

86

83

80

77

74

WB (°F)

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

72

732

488

704

437

700

393

696

356

695

313

—

SHC
—

67

677

564

651

511

641

463

642

423

637

382

631

346

62

660

648

616

616

598

598

588

564

576

515

579

456

72

743

512

712

452

709

405

706

363

703

319

—

—

67

693

598

661

535

653

484

652

438

649

394

642

353

62

680

661

634

634

615

587

600

531

591

481

591

421

72

767

564

731

485

731

433

727

378

722

331

—

—

67

728

677

684

586

680

530

675

472

673

419

666

367

62

725

701

673

673

652

652

627

572

624

515

616

458

72

781

592

741

502

742

448

738

387

731

337

—

—

67

750

713

695

613

694

554

688

490

687

433

679

375

62

750

713

694

613

672

554

642

490

641

433

630

375

72

786

604

746

510

747

454

743

390

736

340

—

—

67

758

720

701

625

701

565

693

497

692

439

685

378

62

760

720

701

602

681

534

648

473

649

416

636

357

* Rated performance is at sea level. Cooling capacities are gross cooling capacity.

95° AIR ON CONDENSER COIL
CAPACITY (MBH) AT ENTERING DRY BULB (°F)
CFM

12000

16000

19250

22000

24000

ENTERING

90

86

83

80

77

74

WB (°F)

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

72

706

479

678

424

673

381

671

344

668

303

—

SHC
—

67

651

554

634

504

621

454

621

411

613

382

610

334

62

641

626

598

598

577

527

575

490

567

444

566

398

72

716

502

687

441

683

394

680

352

677

309

—

—

67

668

585

643

525

633

476

630

427

624

382

620

341

62

661

644

616

616

594

554

585

511

577

462

576

415

72

738

554

708

478

704

422

700

369

696

322

—

—

67

707

671

661

572

659

521

651

462

647

382

642

357

62

705

682

654

654

633

625

605

555

600

502

598

453

72

751

581

719

497

715

438

711

379

707

328

—

—

67

728

701

671

597

673

546

663

481

660

382

654

365

62

730

703

675

675

653

653

616

578

613

524

609

473

72

756

593

723

506

720

444

715

383

711

331

—

—

67

737

709

675

607

678

556

667

489

665

382

659

369

62

740

709

675

607

662

556

620

489

618

382

614

369

* Rated performance is at sea level. Cooling capacities are gross cooling capacity.

14

YORK INTERNATIONAL

FORM 100.50-EG1

TABLE 3 – COOLING PERFORMANCE DATA – 55 TON MODEL (CONT’D)

105° AIR ON CONDENSER COIL
CAPACITY (MBH) AT ENTERING DRY BULB (°F)
CFM

12000

16000

19250

22000

24000

ENTERING

90

86

83

80

77

74

WB (°F)

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

72

642

473

654

416

649

371

647

334

647

292

—

SHC
—

67

593

531

602

489

594

443

595

397

597

359

593

322

62

592

605

581

581

546

512

553

471

549

437

546

390

72

661

493

662

432

658

384

655

342

654

297

—

—

67

619

569

613

513

606

464

605

415

605

372

601

330

62

618

623

598

598

566

542

561

496

558

454

554

405

72

701

535

679

465

678

413

673

360

669

308

—

—

67

679

651

639

565

632

510

626

452

622

398

619

346

62

679

661

634

634

611

606

580

549

578

492

572

436

72

723

558

689

483

689

428

682

370

677

314

—

—

67

711

696

653

593

645

534

637

473

631

412

628

355

62

711

682

653

653

635

641

590

577

588

512

582

453

72

733

567

693

490

693

435

686

374

681

317

—

—

67

724

693

659

605

651

545

642

481

635

418

632

359

62

725

691

661

661

645

656

594

590

593

521

586

460

* Rated performance is at sea level. Cooling capacities are gross cooling capacity.

115° AIR ON CONDENSER COIL
CAPACITY (MBH) AT ENTERING DRY BULB (°F)
CFM

12000

16000

19250

22000

24000

ENTERING

90

86

83

80

77

74

WB (°F)

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

72

657

460

624

400

618

357

613

321

610

284

—

SHC
—

67

606

535

579

477

571

435

566

390

563

350

559

312

62

598

581

557

567

528

517

519

458

517

425

512

381

72

665

482

633

417

627

371

623

330

619

288

—

—

67

623

562

588

498

582

454

577

406

573

362

570

319

62

617

600

572

578

547

539

534

487

528

443

523

395

72

682

529

653

455

647

399

645

350

640

297

—

—

67

660

632

606

544

605

496

599

440

595

388

592

335

62

659

639

602

602

589

587

565

551

552

481

547

426

72

692

554

663

476

658

414

657

360

651

302

—

—

67

680

660

617

568

617

518

611

458

607

402

603

343

62

682

660

616

614

611

613

582

585

565

501

559

443

72

696

565

668

484

663

421

662

365

656

304

—

—

67

689

668

621

578

622

527

617

466

613

408

608

347

62

692

669

622

620

621

624

589

589

570

510

565

450

* Rated performance is at sea level. Cooling capacities are gross cooling capacity.

YORK INTERNATIONAL

15

Cooling Performance Data – 60 Ton Model
TABLE 4 – COOLING PERFORMANCE DATA – 60 TON MODEL

85° AIR ON CONDENSER COIL
CAPACITY (MBH) AT ENTERING DRY BULB (°F)
CFM

14000

18000

21000

24000

27000

ENTERING

90

86

83

80

77

74

WB (°F)

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

72

804

495

804

461

801

277

798

383

792

344

—

SHC
—

67

736

586

728

522

729

339

727

440

725

408

723

377

62

689

689

663

663

658

442

656

543

647

493

654

424

72

846

609

840

538

837

410

833

426

827

372

—

—

67

795

720

773

632

771

504

769

519

767

468

761

415

62

771

771

740

740

725

617

704

630

700

572

699

502

72

867

666

858

576

855

477

851

448

845

386

—

—

67

824

787

795

687

792

587

790

558

787

498

780

434

62

813

813

779

779

759

705

728

673

726

611

722

541

72

888

722

876

614

872

544

868

470

862

401

—

—

67

854

854

818

742

814

670

810

598

808

528

799

453

62

854

854

817

817

792

792

752

716

752

651

744

580

72

897

748

884

632

880

574

876

480

870

407

—

—

67

867

867

828

767

823

708

820

616

818

541

808

461

62

873

873

835

835

808

817

763

736

764

669

755

598

* Rated performance is at sea level. Cooling capacities are gross cooling capacity.

95° AIR ON CONDENSER COIL
CAPACITY (MBH) AT ENTERING DRY BULB (°F)
CFM

14000

18000

21000

24000

27000

ENTERING

90

86

83

80

77

74

WB (°F)

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

72

773

491

771

442

769

336

769

368

763

331

—

SHC
—

67

723

527

692

464

703

397

703

432

699

437

696

363

62

671

671

645

645

631

474

642

505

655

416

673

318

72

814

599

808

524

804

434

802

414

797

361

—

—

67

775

678

752

570

745

529

742

508

736

455

732

402

62

750

750

719

719

699

620

684

604

682

550

681

494

72

834

652

827

565

822

482

819

438

814

376

—

—

67

802

753

783

623

766

594

761

546

755

463

751

421

62

789

789

756

756

732

693

706

653

696

616

685

582

72

854

706

846

607

840

531

835

461

831

391

—

—

67

828

828

813

675

788

660

780

584

774

472

769

441

62

828

828

793

793

766

766

727

703

709

683

689

670

72

864

730

854

626

848

553

843

471

838

397

—

—

67

840

863

827

699

797

691

789

601

782

476

778

450

62

846

846

810

810

782

788

737

726

716

714

690

710

* Rated performance is at sea level. Cooling capacities are gross cooling capacity.

16

YORK INTERNATIONAL

FORM 100.50-EG1

TABLE 4 – COOLING PERFORMANCE DATA – 60 TON MODEL (CONT’D)

105° AIR ON CONDENSER COIL
CAPACITY (MBH) AT ENTERING DRY BULB (°F)
CFM

14000

18000

21000

24000

27000

ENTERING

90

86

83

80

77

74

WB (°F)

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

72

753

500

744

438

741

392

741

357

737

319

—

SHC
—

67

690

469

676

304

672

458

681

416

681

384

678

350

62

652

652

627

627

587

554

616

489

632

454

624

412

72

782

588

778

514

774

457

771

403

767

347

—

—

67

745

635

718

508

713

550

715

494

711

442

708

389

62

726

726

697

697

664

648

658

589

655

536

655

480

72

797

633

794

551

790

490

787

425

782

361

—

—

67

773

718

739

610

734

597

732

533

727

471

723

409

62

763

763

732

732

702

694

679

639

667

576

670

515

72

811

677

811

589

806

522

802

448

798

375

—

—

67

801

801

761

712

754

643

750

572

742

500

738

428

62

800

800

767

767

741

741

700

690

679

617

686

549

72

818

697

818

606

814

537

809

459

804

382

—

—

67

814

839

771

759

764

664

757

589

749

514

744

437

62

817

817

783

783

758

759

710

709

684

636

693

565

* Rated performance is at sea level. Cooling capacities are gross cooling capacity.

115° AIR ON CONDENSER COIL
CAPACITY (MBH) AT ENTERING DRY BULB (°F)
CFM

14000

18000

21000

24000

27000

ENTERING

90

86

83

80

77

74

WB (°F)

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

72

726

485

711

413

702

376

698

345

689

309

—

SHC
—

67

629

574

647

512

647

447

643

411

635

370

633

338

62

626

626

607

622

562

543

561

467

582

447

574

404

72

749

572

742

496

736

440

732

389

726

335

—

—

67

700

673

688

603

683

537

680

484

673

429

669

376

62

699

699

666

673

639

629

625

578

620

524

617

472

72

760

615

758

538

754

473

749

411

744

349

—

—

67

736

722

708

648

701

582

699

521

692

458

687

395

62

735

735

695

698

677

672

657

634

640

563

638

505

72

772

658

774

580

771

505

766

433

763

362

—

—

67

772

772

728

693

718

627

717

558

711

487

706

414

62

772

772

724

724

715

715

690

690

659

602

659

539

72

777

678

781

599

779

520

773

443

771

368

—

—

67

788

788

737

714

727

647

726

574

719

501

714

423

62

788

788

737

735

732

733

704

706

668

619

669

555

* Rated performance is at sea level. Cooling capacities are gross cooling capacity.

YORK INTERNATIONAL

17

Cooling Performance Data – 65 Ton Model
TABLE 5 – COOLING PERFORMANCE DATA – 65 TON MODEL

85° AIR ON CONDENSER COIL
CAPACITY (MBH) AT ENTERING DRY BULB (°F)
CFM

14000

18000

21000

24000

27000

ENTERING

90

86

83

80

77

74

WB (°F)

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

72

840

584

839

516

836

467

833

418

828

368

—

SHC
—

67

785

669

774

605

771

554

772

502

768

456

764

406

62

754

754

724

724

695

640

710

589

707

542

706

492

72

853

615

851

540

848

486

844

431

840

377

—

—

67

802

713

788

638

784

582

784

525

780

473

776

418

62

779

779

748

748

719

676

723

620

719

568

717

513

72

876

668

871

582

868

518

864

454

859

392

—

—

67

827

788

810

694

806

630

804

563

800

502

796

439

62

821

821

787

787

760

739

745

674

741

612

737

548

72

899

721

892

623

888

550

884

477

878

407

—

—

67

862

862

833

750

828

678

824

601

820

531

815

460

62

862

862

827

827

801

801

767

727

762

656

757

584

72

909

745

901

642

898

564

893

488

887

413

—

—

67

878

878

843

776

838

700

833

619

829

544

824

469

62

878

878

843

765

820

686

777

604

772

530

766

455

* Rated performance is at sea level. Cooling capacities are gross cooling capacity.

95° AIR ON CONDENSER COIL
CAPACITY (MBH) AT ENTERING DRY BULB (°F)
CFM

14000

18000

21000

24000

27000

ENTERING

90

86

83

80

77

74

WB (°F)

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

72

810

572

808

504

806

454

802

405

798

357

—

SHC
—

67

767

658

747

593

743

542

744

491

740

443

737

393

62

733

733

704

704

676

631

686

581

682

530

680

477

72

822

603

820

528

817

473

813

419

809

365

—

—

67

782

699

759

625

756

570

755

513

751

460

748

406

62

756

756

726

726

699

664

697

610

694

556

691

500

72

844

656

839

569

836

505

832

442

827

380

—

—

67

800

768

781

681

777

618

774

551

770

489

766

426

62

797

797

764

764

737

720

717

661

714

600

710

538

72

866

709

858

610

855

537

850

464

844

394

—

—

67

837

837

802

737

798

665

793

589

788

519

784

447

62

837

837

802

802

776

776

737

712

734

644

729

577

72

875

733

867

629

863

552

859

475

852

401

—

—

67

854

854

812

762

807

687

801

606

797

532

792

456

62

854

854

812

753

794

674

746

592

743

518

738

441

* Rated performance is at sea level. Cooling capacities are gross cooling capacity.

18

YORK INTERNATIONAL

FORM 100.50-EG1

TABLE 5 – COOLING PERFORMANCE DATA – 65 TON MODEL (CONT’D)

105° AIR ON CONDENSER COIL
CAPACITY (MBH) AT ENTERING DRY BULB (°F)
CFM

14000

18000

21000

24000

27000

ENTERING

90

86

83

80

77

74

WB (°F)

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

72

780

560

777

493

774

442

771

393

768

342

—

SHC
—

67

737

646

717

581

714

529

714

476

711

430

708

381

62

710

710

682

682

650

621

658

565

655

516

653

466

72

792

591

788

516

785

461

781

406

777

351

—

—

67

753

683

730

613

726

556

725

499

721

447

718

393

62

732

732

703

703

672

650

669

595

666

542

663

486

72

812

643

805

555

802

493

798

429

794

365

—

—

67

771

746

752

668

746

604

744

538

738

476

734

413

62

771

771

739

739

711

700

689

647

685

586

681

522

72

831

696

822

595

820

524

816

452

810

379

—

—

67

809

809

774

722

766

651

762

576

756

505

751

433

62

809

809

774

774

750

750

709

698

704

630

699

558

72

840

720

830

613

828

539

823

462

817

386

—

—

67

826

826

784

747

775

673

770

594

763

518

759

442

62

826

826

791

791

767

772

718

721

712

650

707

574

* Rated performance is at sea level. Cooling capacities are gross cooling capacity.

115° AIR ON CONDENSER COIL
CAPACITY (MBH) AT ENTERING DRY BULB (°F)
CFM

14000

18000

21000

24000

27000

ENTERING

90

86

83

80

77

74

WB (°F)

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

SHC

CAP

72

748

548

744

478

742

429

738

378

735

330

—

SHC
—

67

708

639

690

570

686

517

684

463

681

417

678

368

62

681

681

664

664

621

608

625

550

628

503

625

452

72

759

578

754

502

752

448

748

392

744

338

—

—

67

724

671

700

599

696

544

694

486

690

434

687

380

62

704

704

679

679

644

634

642

583

638

528

635

473

72

776

629

771

543

768

479

766

415

759

352

—

—

67

741

725

716

650

714

591

711

523

706

462

703

400

62

741

741

706

706

682

678

669

640

655

571

651

508

72

794

680

789

584

784

511

784

438

774

366

—

—

67

779

779

732

700

732

637

728

561

722

491

718

419

62

779

779

732

732

721

721

697

697

672

615

668

543

72

802

703

797

603

791

525

792

449

781

372

—

—

67

796

796

740

723

740

658

736

578

729

504

725

428

62

796

796

740

717

738

648

710

563

680

490

676

414

* Rated performance is at sea level. Cooling capacities are gross cooling capacity.

YORK INTERNATIONAL

19

Fan Performance
TABLE 6 – 50 THROUGH 65 TON SUPPLY FAN DATA
CFM
STD. AIR
10000
12000
14000
16000
17500
18000
19250
20000
21000
22000
22500
24000
26000
27000

0.50
RPM
HP
249
1.7
269
2.5
290
3.6
312
5.1
329
6.3
334
6.8
348
8.1
357
8.9
370
10.1
383
11.4
387
12.0
398
13.9
417
16.8
429
18.6

TOTAL STATIC PRESSURE (inches of water column)
1.00
1.50
2.00
2.50
RPM
HP
RPM
HP
RPM
HP
RPM
HP
321
2.5
382
3.3
––
––
––
––
335
3.4
392
4.4
443
5.3
493
6.4
352
4.7
405
5.8
454
6.9
497
8.0
371
6.3
421
7.5
467
8.7
510
10.0
386
7.7
435
9.0
478
10.4
519
11.7
391
8.2
439
9.6
482
10.9
522
12.3
404
9.6
451
11.1
493
12.5
532
14.0
412
10.5
458
12.1
499
13.5
538
15.1
423
11.9
468
13.5
510
15.1
547
16.7
434
13.3
478
15.0
520
16.7
555
18.3
440
14.1
484
15.8
524
17.6
560
19.2
458
16.6
500
18.4
537
20.2
574
22.1
478
20.2
520
22.3
559
24.4
593
26.3
490
22.3
533
24.6
572
26.8
602
28.6

3.00
RPM
HP
––
—
––
—
540
9.1
549
11.2
558
13.1
561
13.8
570
15.5
575
16.6
583
18.3
591
20.0
595
20.9
607
23.8
626
28.3
638
30.9

TABLE 6 – 50 THROUGH 65 TON SUPPLY FAN DATA (CONT’D)
CFM
STD. AIR
10000
12000
14000
16000
17500
18000
19250
20000
21000
22000
22500
24000
26000
27000

20

3.50
RPM
HP
––
––
––
––
585
10.5
587
12.5
595
14.5
597
15.2
605
17.1
609
18.2
617
19.9
624
21.7
628
22.7
640
25.7
656
30.2
665
32.7

TOTAL STATIC PRESSURE (inches of water column)
4.00
4.50
5.00
5.50
RPM
HP
RPM
HP
RPM
HP
RPM
HP
––
––
––
––
––
––
––
––
––
––
––
––
––
––
––
––
––
––
––
––
––
––
––
––
622
13.8
663
15.4
700
17.0
––
––
629
15.9
664
17.3
697
18.8
549
15.9
631
16.6
664
18.0
696
19.5
732
21.2
638
18.6
670
20.1
702
21.6
734
23.3
642
19.8
674
21.4
705
22.9
735
24.5
649
21.6
681
23.3
710
24.9
740
26.6
655
23.4
688
25.3
715
26.9
744
28.6
659
24.4
691
26.3
719
28.0
748
29.8
671
27.5
700
29.4
729
31.4
759
33.4
687
32.2
716
34.2
742
36.1
769
38.2
693
34.6
723
36.8
751
38.9
778
41.0

6.00
RPM
HP
––
––
––
––
––
––
––
––
575
17.3
766
23.0
765
25.0
764
26.1
769
28.2
773
30.4
776
31.5
783
35.1
798
40.5
802
43.1

YORK INTERNATIONAL

FORM 100.50-EG1

TABLE 7 – 50 THROUGH 65 TON EXHAUST FAN DATA
CFM
STD. AIR
10000
12000
14000
16000
18000
20000

0.50
RPM
HP
674
3.30
713
4.84
762
6.84
819
9.36
879 12.42
943 16.18

YORK INTERNATIONAL

TOTAL STATIC PRESSURE (inches of water column)
1.00
1.50
2.00
2.50
RPM
HP
RPM
HP
RPM
HP
RPM
HP
801
4.18
––
–––
––
––
––
––
823
5.82 929
6.87
––
––
––
––
858
7.98 952
9.12 1043 10.32 1132 11.62
904 10.73 988 12.04 1070 13.33 1150 14.69
957 14.04 1032 15.56 1107 17.02 1179 18.48
1014 18.04 ––
––
––
––
––
––

3.00
RPM
HP
––
––
––
––
––
––
1229 16.10
––
––
––
––

21

Fan Performance (continued)
TABLE 8 – COMPONENT STATIC PRESSURE DROPS (INCHES OF WATER COLUMN)

SIZE

50

55

60

65

*

22

AIR FLOW

EVAPORATOR

SUPPLY

RETURN AIR

COILS

OPENING

OPENING

CFM STD. AIR

FILTERS
2"

2"

2"

THROW- CLEAN- PLEAT-

WET

DRY

BOTTOM LEFT RIGHT BOTTOM REAR SIDES

10000

0.22

0.15

0.04

0.08

0.08

0.04

0.06

0.04

12000

0.30

0.21

0.06

0.11

0.11

0.06

0.09

0.06

14000

0.38

0.27

0.09

0.15

0.15

0.08

0.12

0.09

AWAY

2"
CARBON

ABLE

ED

0.05

0.01

0.04

0.07

0.02

0.06

0.11

0.09

0.03

0.07

0.14

0.08

16000

0.47

0.35

0.11

0.20

0.20

0.11

0.15

0.11

0.11

0.04

0.09

0.16

17500

0.54

0.41

0.14

0.24

0.24

0.13

0.18

0.14

0.12

0.05

0.10

0.19

18000

0.57

0.44

0.14

0.25

0.25

0.13

0.19

0.14

0.13

0.05

0.10

0.19

20000

0.67

0.53

0.18

0.31

0.31

0.17

0.24

0.18

0.15

0.06

0.12

0.22

21000

0.72

0.58

0.20

0.35

0.35

0.18

0.26

0.20

0.16

0.07

0.13

0.24

22000

0.78

0.63

0.21

0.38

0.38

0.20

0.29

0.21

0.17

0.08

0.14

0.26

22500

0.80

0.66

0.22

0.40

0.40

0.21

0.30

0.22

0.17

0.08

0.15

0.26

12000

0.30

0.21

0.06

0.11

0.11

0.06

0.09

0.06

0.07

0.02

0.06

0.11

14000

0.38

0.27

0.09

0.15

0.15

0.08

0.12

0.09

0.09

0.03

0.07

0.14

16000

0.47

0.35

0.11

0.20

0.20

0.11

0.15

0.11

0.11

0.04

0.09

0.16

18000

0.57

0.44

0.14

0.25

0.25

0.13

0.19

0.14

0.13

0.05

0.10

0.19

19250

0.63

0.49

0.16

0.29

0.29

0.15

0.22

0.16

0.14

0.06

0.12

0.21

20000

0.67

0.53

0.18

0.31

0.31

0.17

0.24

0.18

0.15

0.06

0.12

0.22

22000

0.78

0.63

0.21

0.38

0.38

0.20

0.29

0.21

0.17

0.08

0.14

0.26

24000

0.89

0.74

0.25

0.45

0.45

0.24

0.34

0.25

0.19

0.09

0.16

0.29

14000

0.38

0.27

0.09

0.15

0.15

0.08

0.12

0.09

0.09

0.03

0.07

0.14

16000

0.47

0.35

0.11

0.20

0.20

0.11

0.15

0.11

0.11

0.04

0.09

0.16

18000

0.57

0.44

0.14

0.25

0.25

0.13

0.19

0.14

0.13

0.05

0.10

0.19

20000

0.67

0.53

0.18

0.31

0.31

0.17

0.24

0.18

0.15

0.06

0.12

0.22

21000

0.72

0.58

0.20

0.35

0.35

0.18

0.26

0.20

0.16

0.07

0.13

0.24

22000

0.78

0.63

0.21

0.38

0.38

0.20

0.29

0.21

0.17

0.08

0.14

0.26

24000

0.89

0.74

0.25

0.45

0.45

0.24

0.34

0.25

0.19

0.09

0.16

0.29

26000

1.01

0.86

0.30

0.53

0.53

0.28

0.40

0.30

0.21

0.11

0.19

0.32

27000

1.07

0.92

0.32

0.57

0.57

0.30

0.43

0.32

0.23

0.12

0.20

0.34

14000

0.38

0.27

0.09

0.15

0.15

0.08

0.12

0.09

0.09

0.03

0.07

0.14

16000

0.47

0.35

0.11

0.20

0.20

0.11

0.15

0.11

0.11

0.04

0.09

0.16

18000

0.57

0.44

0.14

0.25

0.25

0.13

0.19

0.14

0.13

0.05

0.10

0.19

20000

0.67

0.53

0.18

0.31

0.31

0.17

0.24

0.18

0.15

0.06

0.12

0.22

21000

0.72

0.58

0.20

0.35

0.35

0.18

0.26

0.20

0.16

0.07

0.13

0.24

22000

0.78

0.63

0.21

0.38

0.38

0.20

0.29

0.21

0.17

0.08

0.14

0.26

24000

0.89

0.74

0.25

0.45

0.45

0.24

0.34

0.25

0.19

0.09

0.16

0.29

26000

1.01

0.86

0.30

0.53

0.53

0.28

0.40

0.30

0.21

0.11

0.19

0.32

27000

1.07

0.92

0.32

0.57

0.57

0.30

0.43

0.32

0.23

0.12

0.20

0.34

For Aluminum Fins Only

YORK INTERNATIONAL

FORM 100.50-EG1

FILTERS
RIGID FILTER

ECONOMIZER

ECONOMIZER DAMPERS
POWERED

12" RIGID

12" RIGID

FRESH AIR

MANUAL OR

0 - 100%

65%*

95%*

OPENINGS

2-POSITION

MODULATION

0.05

0.21

0.30

0.07

0.05

0.11

0.07

0.28

0.38

0.11

0.08

0.16

0.11

0.09

0.34

0.46

0.15

0.11

0.21

0.15

0.11

0.42

0.55

0.20

0.14

0.26

0.20

0.12

0.47

0.62

0.24

0.17

0.31

0.24

0.13

0.49

0.65

0.25

0.18

0.32

0.25

0.15

0.58

0.74

0.31

0.22

0.39

0.31

0.16

0.62

0.79

0.35

0.24

0.42

0.34

0.17

0.66

0.84

0.38

0.27

0.46

0.37

0.17

0.68

0.87

0.40

0.28

0.48

0.39

0.07

0.28

0.38

0.11

0.08

0.16

0.11

0.09

0.34

0.46

0.15

0.11

0.21

0.15

RACK NO.
MEDIA

EXHAUST

0.08

0.11

0.42

0.55

0.20

0.14

0.26

0.20

0.13

0.49

0.65

0.25

0.18

0.32

0.25

0.14

0.54

0.71

0.29

0.20

0.36

0.29

0.15

0.58

0.74

0.31

0.22

0.39

0.31

0.17

0.66

0.84

0.38

0.27

0.46

0.37

0.19

0.75

0.95

0.46

0.32

0.54

0.45

0.09

0.34

0.46

0.15

0.11

0.21

0.15

0.11

0.42

0.55

0.20

0.14

0.26

0.20

0.13

0.49

0.65

0.25

0.18

0.32

0.25

0.15

0.58

0.74

0.31

0.22

0.39

0.31

0.16

0.62

0.79

0.35

0.24

0.42

0.34

0.17

0.66

0.84

0.38

0.27

0.46

0.37

0.19

0.75

0.95

0.46

0.32

0.54

0.45

0.21

0.84

1.06

0.55

0.37

0.62

0.52

0.23

0.89

1.11

0.59

0.40

0.67

0.56

0.09

0.34

0.46

0.15

0.11

0.21

0.15

0.11

0.42

0.55

0.20

0.14

0.26

0.20

0.13

0.49

0.65

0.25

0.18

0.32

0.25

0.15

0.58

0.74

0.31

0.22

0.39

0.31

0.16

0.62

0.79

0.35

0.24

0.42

0.34

0.17

0.66

0.84

0.38

0.27

0.46

0.37

0.19

0.75

0.95

0.46

0.32

0.54

0.45

0.21

0.84

1.06

0.55

0.37

0.62

0.52

0.23

0.89

1.11

0.59

0.40

0.67

0.56

YORK INTERNATIONAL

23

Electrical Data
ELECTRICAL SERVICE SIZING
• LOAD3 is the current of the electric heaters – zero
for cooling only units.
• LOAD4 is the sum of any remaining currents
greater than or equal to 1.0 amp

In order to use the electrical service required for the
cooling only Eco2 rooftop, use the appropriate calculations listed below from U.L. 1995. Based on the operating mode and configuration of the rooftop, the calculations will yield different MCA (minimum circuit ampacity), and MOP (maximum overcurrent protection).

Use the following calculations to determine MCA
and MOP for units supplied with a single-point power
connection:

Using the following load definitions and calculations,
determine the correct electrical sizing for your unit. All
concurrent load conditions must be considered in the
calculations, and you must use the highest value for
any combination of loads.

MCA = (1.25 x LOAD1) + LOAD2 + LOAD4
MOP = (2.25 x LOAD1) + LOAD2 + LOAD4

Load Definitions:

If the MOP does not equal a standard current rating of
an overcurrent protective device, then the marked maximum rating is to be the next lower standard rating. However, if the device selected for MOP is less than the
MCA, then select the lowest standard maximum fuse
size greater than or equal to the MCA.

• LOAD1 is the current of the largest motor – compressor or fan motor.
• LOAD2 is the sum of the remaining motor currents
that may run concurrently with LOAD1 (i.e., exhaust
fan motor).

TABLE 9 – COMPRESSORS
COMPRESSOR
QUANTITY
MODEL

PER

MODEL

UNIT

NOMINAL VOLTAGE
208V

230V

460V

575V

RLA*

LRA*

RLA*

LRA*

RLA*

LRA*

RLA*

LRA*

50

4

SZ160

54.0

265.0

48.8

265.0

24.2

135.0

19.4

120.0

55

4

SZ160

54.0

265.0

48.8

265.0

24.2

135.0

19.4

120.0

60

4

SZ185

62.3

380.0

56.3

380.0

27.9

175.0

22.3

140.0

65

4

SZ185

62.3

380.0

56.3

380.0

27.9

175.0

22.3

140.0

* Values shown are per compressor

24

YORK INTERNATIONAL

FORM 100.50-EG1

TABLE 10 – SUPPLY AND EXHAUST FAN MOTOR (ODP OR TEFC)
High Efficiency
MOTOR
HP
5.0
7.5
10.0
15.0
20.0
25.0
30.0
40.0

208V
FLA
14.0
22.2
28.5
44.8
61.0
74.0
87.0
113.0

Premium Efficiency
NOMINAL VOLTAGE
230V
460V
FLA
FLA
13.4
6.7
21.6
10.8
28.4
14.2
39.0
19.5
50.0
25.0
60.0
30.0
76.0
38.0
95.6
47.8

575V
FLA
5.3
8.2
11.4
16.0
20.0
24.2
30.3
38.0

TABLE 11 – CONDENSER FAN MOTORS / EACH

NOMINAL
TONS
50
55
60
65

208V
FLA
7.5
7.5
7.5
7.5

YORK INTERNATIONAL

NOMINAL VOLTAGE
230V
460V
FLA
FLA
6.8
3.4
6.8
3.4
6.8
3.4
6.8
3.4

575V
FLA
2.7
2.7
2.7
2.7

MOTOR
HP
5.0
7.5
10.0
15.0
20.0
25.0
30.0
40.0

208V
FLA
14.9
22.5
29.2
41.5
55.0
71.0
85.5
109.0

NOMINAL VOLTAGE
230V
460V
FLA
FLA
13.6
6.8
20.0
10.0
25.8
12.9
36.0
18.0
48.0
24.0
61.0
30.5
74.0
37.0
96.0
48.0

575V
FLA
5.5
7.9
10.3
14.5
19.3
24.5
30.0
38.0

TABLE 12 – CONTROLS AND CONVENIENCE
OUTLET

DESCRIPTION
Control Transformer
Convenience Outlet

NOMINAL VOLTAGE
208V 230V 460V 575V
AMPS AMPS AMPS AMPS
3.6
3.3
1.6
3.3
9.6
8.7
4.3
3.5

25

Controls
CONTROL SEQUENCES FOR ALL UNITS
GENERAL

ECONOMIZER OPERATION

The control system for the YORK eco2 Packaged Rooftop Unit is fully self-contained and based around an
OptiLogic™ rooftop unit controller. To aid in unit setup,
maintenance, and operation, the OptiLogic™ rooftop
unit controller is equipped with a user interface that is
based around a 4 line x 20 character backlit LCD display. The LCD displays plain language text in a menudriven format to facilitate use. In addition to the display,
the OptiLogic™ user interface is also equipped with an
LED indicator light, which will warn of any abnormal
operation of the equipment or communication failures.

The unit can be equipped with one of three types of
optional economizers, dry bulb, single enthalpy, or comparative enthalpy. When the unit controller determines
that Outside Air is suitable for economizing, the unit
controller will control the outside air damper(s) open to
provide economizer cooling. If economizer cooling alone
is insufficient for the cooling load, the unit controller
shall stage up compressors, one at a time, to meet
demand.

For the maximum in system flexibility, the YORK ECO2
Packaged Rooftop Unit can be operated by either a
typical 7-wire thermostat (2 cool / 2 heat), a space temperature sensor, or stand-alone (VAV only). Note, a field
wiring terminal block is provided to facilitate unit setup
and installation.

The control logic for the three types of economizers is
as follows:
Dry Bulb Economizer

In lieu of the hard-wired control options, the OptiLogic™
rooftop unit controller can be connected to and operated by a Building Automation System (BAS). If required, the OptiLogic™ rooftop unit controller can be
equipped with an optional BACNet IP communication
card, which allows communication, via Ethernet, to a
BACNet IP based BAS.

The dry bulb economizer is the default economizer control scheme. With the dry bulb economizer, the unit controller monitors the Outside Air temperature only and
compares it to a reference temperature setting. Outside
Air is deemed suitable for economizing when the Outside Air temperature is determined to be less than the
reference temperature setting. This method of economizing is effective, but is prone to some changeover inefficiencies due to the fact that this method is based on
sensible temperatures only and does not take Outside
Air moisture content into consideration.

UNOCCUPIED / OCCUPIED SWITCHING

Single Enthalpy Economizer

Depending on application, the unit can be indexed between unoccupied and occupied modes of operation
by one of three methods, hard-wired input, internal time
clock, or BAS. A contact-closure input is provided for
hard-wiring to an external indexing device such as a
central time clock, thermostat with built in scheduling,
or a manual switch. The unit controller is also equipped
with a built in 7-day time clock which can be used, in
lieu of the contact closure input, to switch the unit between Unoccupied and Occupied modes of operation.
The internal time clock is fully configurable via the user
interface and includes Holiday scheduling. In addition
to the hard-wired input or the internal time clock, the
unit can also be indexed between unoccupied and occupied modes of operation via a BAS command.
Note a unit operated from a space sensor can be
equipped to temporarily override an unoccupied mode
of operation. This Unoccupied Override feature is fully
configurable via the OptiLogic™ user interface.

26

With the optional single enthalpy economizer, the unit
controller monitors the Outside Air enthalpy in addition
to the Outside Air temperature and compares it to a
reference enthalpy setting and a reference temperature setting. Outside Air is deemed suitable for economizing when the Outside Air enthalpy is determined to
be less than the reference enthalpy setting and the Outside Air temperature is less than the reference temperature setting. This method of economizing allows
the reference temperature setting to be set higher than
the DB Economizer and is consequently a more efficient packaged rooftop economizer.
Comparative Enthalpy Economizer
With the optional comparative enthalpy economizer, the
unit controller monitors and compares the Outside Air
and Return Air enthalpies in addition to comparing the
Outside Air temperature to the reference temperature
setting. Outside Air is deemed suitable for economizing when the Outside Air enthalpy is determined to be

YORK INTERNATIONAL

FORM 100.50-EG1

less than the Return Air enthalpy and the Outside Air
temperature is less than the reference temperature setting. This method of economizing is the most accurate
and provides the highest degree of energy efficiency
for a packaged rooftop economizer.
VENTILATION CONTROL SEQUENCES
Minimum OA Damper Position (CV Units)
When the unit goes into the Occupied mode of operation, the unit controller shall open the Outside Air
Damper to a fixed minimum position. The damper shall
remain at this position as long as the unit is in the occupied mode. The minimum position may be overridden
more open by the unit controller when Outside Air conditions are suitable for economizing.
Minimum OA Damper Position (VAV Units)
With Variable Air Volume units, there are two Minimum
OA Damper Positions, one when the unit is at full speed
and the second when the unit is at approximately half
speed. These two points allow the control to linearly
reset the position of the OA damper in response to fan
speed.
When the unit goes into the Occupied mode of operation, the unit controller shall monitor the speed of the
supply fan and open the Outside Air damper to a calculated minimum position based on the fan speed. This
minimum position shall vary as the speed of the fan
changes. The damper shall remain at this calculated
position as long as the unit is in the occupied mode.
The minimum position may be overridden more open
by the unit controller when Outside Air conditions are
suitable for economizing.
Air Measurement Stations
When the unit is equipped with an air measurement
station, the unit controller shall control the Outside Air
damper to a measured flow rate through the Air Measurement Station.
When the unit goes into the Occupied mode of operation, the unit controller shall control the Outside Air
damper to maintain the Minimum AirFlow Setpoint
through the Air Measurement Station. The unit controller shall control the Outside Air damper to this flow rate
as long as the unit is in the Occupied mode. The Outside Air damper may be overridden more open by the
unit controller when Outside Air conditions are suitable
for economizing.

YORK INTERNATIONAL

Demand Ventilation
If an optional CO2 sensor is connected to the unit, the
unit controller can reset the minimum OA damper
position(s) or minimum flow rate based on demand.
The unit controller shall monitor the CO2 level within the
building. If the CO2 level rises above the CO2 setpoint,
the controller will temporarily increase the Minimum OA
Damper Position or Minimum OA flow rate to increase
ventilation. If the CO2 level drops below the CO2 setpoint, the controller will decrease the Minimum OA
Damper Position or Minimum OA flow rate to decrease
ventilation.
Demand Ventilation shall remain active as long as the
unit is in the Occupied mode of operation.
EXHAUST CONTROL SEQUENCES
Barometric
The optional barometric exhaust system consists of a
lightweight barometric relief damper installed on the end
of the unit in the Return Air section. As more outside air
is introduced into the controlled zone due to Economizer and Ventilation control sequences, the pressure
inside the building rises. This increase in building pressure forces the barometric relief damper open to allow
exhaust air to escape. Because this type of exhaust
system is not powered, it is limited to small amounts of
exhaust.
Powered Fixed Volume Exhaust Based on
Outside Air Damper Position
This optional fixed volume powered exhaust system
consists of a fixed speed fan that is controlled ON and
OFF based on the position of the Outside Air Damper.
During operation, when the Outside Air Damper opens
to a selected turn-on point, the Exhaust Fan is cycled
ON. The fan remains on as long as the Outside Air
damper is above a selected turn-off point. If the Outside Air Damper closes to the selected turn-off point,
the Exhaust Fan is cycled OFF. The turn-on and turnoff points are user selectable from the OptiLogic™ User
Interface panel.
Powered Fixed Volume Exhaust Based on
Building Pressure
This optional fixed volume powered exhaust system
consists of a fixed speed fan that is controlled ON and
OFF based on the pressure inside the building. During

27

Controls (continued)
operation, the pressure within the building in monitored
by the OptiLogic™ controller. If the pressure rises to or
above a selected turn-on pressure, the Exhaust Fan is
cycled ON. The fan shall remain on as long as the pressure within the building remains above a selected turnoff pressure. If the building pressure falls to or below
the selected turn-off pressure, the Exhaust Fan is cycled
OFF. The turn-on and turn-off pressure setpoints are
user selectable from the OptiLogic™ User Interface.
Powered Variable Volume Exhaust-Discharge
Damper Controlled
This optional variable volume powered exhaust system
consists of a fixed speed fan configured with a proportionally controlled discharge damper. The OptiLogic™
controller monitors the pressure inside the building and
controls the Exhaust Damper and the Exhaust Fan. If
the Building Pressure rises, the Exhaust Damper is proportionally controlled open and the Exhaust Fan is controlled ON. If the Building Pressure falls, the Exhaust
Damper is proportionally controlled closed and the Exhaust Fan is controlled OFF. The position of the Exhaust Damper in which the Exhaust Fan is controlled
ON and OFF as well as the Building Pressure setpoint
is user selectable from the OptiLogic™ User Interface.
Powered Variable Volume Exhaust-VFD
Controlled
This optional variable volume powered exhaust system
consist of an Exhaust Fan driven by a Variable Frequency Drive (VFD), which is controlled by the
OptiLogic™ controller. The OptiLogic™ controller monitors the pressure within the building. As the pressure
rises, the VFD is controlled to increase Exhaust Fan
speed. As the pressure falls, the VFD is controlled to
decrease Exhaust Fan speed. The Building Pressure
Setpoint is user selectable from the OptiLogic™ User
Interface.
LOW AMBIENT OPERATION
The OptiLogic™ controller continuously monitors the
outside air temperature to determine if mechanical cooling should be allowed. As a safety, if the Outside Air
temperature falls to or below the Low Ambient Lockout
temperature, mechanical cooling is prevented from operating. For units with economizers, the Low Ambient
Lockout temperature is typically low enough that mechanical cooling will rarely be required. However, for
some applications mechanical cooling is required when
the Outside Air temperature is lower than the Low Ambient Lockout temperature.

28

For these applications, the unit can be equipped with
optional Low Ambient controls. For optional Low Ambient operation, the OptiLogic™ controller monitors the
refrigeration system discharge pressure and controls
the speed of the condenser fans. If the discharge pressure falls, the speeds of the condenser fans are reduced to maintain acceptable condensing pressures in
the refrigeration system. With the optional Low Ambient controls, mechanical cooling is allowed down to
Outside Air temperatures of 0°F.
SMOKE PURGE SEQUENCES
General
As a convenience, for when buildings catch fire or the
building is inundated with smoke or fumes from manufacturing processes, etc., the OptiLogic™ control system provides one of five ventilation override control sequences for building purge. The five selectable purge
sequences are, Shutdown, Pressurization, Exhaust,
Purge and Purge with duct pressure control. Note, when
any of the purge sequences are activated, cooling and
heating modes are disabled. A contact closure is provided which indexes the OptiLogic™ controller into the
selected purge sequence.
Shutdown
When this purge sequence is selected and activated,
the supply and exhaust fans are controlled OFF and
the Outside Air damper is overridden closed. This idle
state is maintained until the purge input is deactivated
and the unit returns to normal operation.
Pressurization
When this purge sequence is selected and activated,
the exhaust fan is controlled OFF and the Supply Fan
is controlled ON. The Outside Air damper is opened
full and the Return Air Damper is closed full. If the unit
is a VAV unit, the VAV boxes are also driven full open to
prevent duct over-pressurization. This mode is maintained until the smoke purge input is deactivated and
the unit returns to normal operation.
Exhaust
When this purge sequence is selected and activated,
the Supply Fan is controlled OFF and the Exhaust Fan
is controlled ON (Exhaust Damper driven full open).
This mode is maintained until the smoke purge input is
deactivated and the unit returns to normal operation.

YORK INTERNATIONAL

FORM 100.50-EG1

Purge
When this purge sequence is selected and activated,
the Supply Fan is controlled ON and the Exhaust Fan
is controlled ON. The Outside Air damper is opened
full and the Return Air damper is closed full. If the unit
is a VAV unit, the VAV boxes are also driven full open to
prevent duct over-pressurization. This mode is maintained until the smoke purge input is deactivated and
the unit returns to normal operation.
Purge With Duct Pressure Control (VAV Only)
When this purge sequence is selected and activated,
the Supply Fan is cycled ON and controlled to maintain
the duct static pressure setpoint. The Exhaust Fan is
also controlled ON (Exhaust Damper driven full open)
and the Outside Air Damper is driven full open. This
mode is maintained until the smoke purge input is deactivated and the unit returns to normal operation.
VAV SPECIFIC SEQUENCES
Supply fan operation
For VAV units, the supply fan is controlled ON and OFF
based on the occupancy state or the G input from a
Thermostat (Unit must be configured for Thermostat
operation to respond to the G input). When the unit
goes into the Occupied mode of operation (or “G” is
called) the Supply Fan will be controlled ON. The
OptiLogic™ controller will monitor the static pressure
within the supply duct system and control the speed of
the supply fan to maintain a specified Duct Static Pressure setpoint. A Variable Frequency Drive (VFD) is used
on all VAV units to vary the speed of the supply fan.
Note, the use of a VFD in lieu of inlet guide vanes provides for higher energy efficiency for the unit by eliminating the losses (air pressure drop) typical of inlet guide
vane systems.
COOLING OPERATION
Thermostat Control
When a VAV unit is configured for thermostat operation, the OptiLogic™ controller will command the Supply Fan to start when the unit goes into the Occupied
mode or a thermostat “G” signal is received by the control. With no thermostat calls for cooling, the unit shall
remain idle with the Supply Fan operating as required.

YORK INTERNATIONAL

When a Cooling Stage 1 call (“Y1”) is received, and the
unit is equipped with an economizer, the OptiLogic™
controller will check the Outside Air conditions to determine if conditions are suitable for economizing and
modulate the outside air damper and or stage up compressors as required to maintain the VAV High Supply
Air Temperature Setpoint. This setpoint is user selectable at the OptiLogic™ User Interface. The OptiLogic™
controller will control to this setpoint as long as Cooling
Stage 1 (“Y1”) remains active.
When a Cooling Stage 2 call (“Y2”) is received, and the
unit is equipped with an economizer, the OptiLogic™
controller will check the Outside Air conditions to determine if conditions are suitable for economizing and
modulate the outside air damper and or stage up compressors as required to maintain the VAV Low Supply
Air Temperature Setpoint. This setpoint is user selectable at the OptiLogic™ User Interface. The OptiLogic™
controller will control to this setpoint as long as Cooling
Stage 2 (“Y2”) remains active.
The VAV High SAT Setpoint is always greater than the
VAV Low SAT Setpoint and because of this essentially
makes this control sequence a Supply Air Temperature Reset algorithm based on Zone Temperature.
Zone Sensor Control
When a VAV unit is configured for Zone Sensor operation, the OptiLogic™ controller will monitor a reference
Zone Temperature and command the Supply Fan to
start when the unit goes into the Occupied mode.
If the zone temperature is above the VAV Setpoint for
SAT Reset, the OptiLogic™ controller will modulate the
outside air damper (Economizer available and conditions suitable) and/or stage compressors up and down,
as required, to maintain the VAV High Supply Air Temperature Setpoint.
If the zone temperature is below or falls below the VAV
Setpoint for SAT Reset, the OptiLogic™ controller will
modulate the Outside Air Damper (Economizer available and conditions suitable) and/or stage compressors up and down, as required, to maintain the VAV
Low Supply Air Temperature Setpoint.
As with thermostat operation, this sequence is also a
Supply Air Temperature Reset algorithm based on Zone
Temperature.

29

Controls (continued)
Stand Alone Control
If the unit is not configured for Thermostat or Zone Sensor operation, the unit will operate in Stand Alone Mode.
In Stand Alone Mode, the OptiLogic™ Controller will
monitor only the Occupied/Unoccupied state. When the
unit is commanded into the Occupied Mode of operation, the OptiLogic™ Controller will start the Supply Fan.
If the unit is equipped with an Economizer, the Controller will check to see if Outside Air conditions are suitable for Economizing. The controller will then use Outside Air (when available and suitable) and/or stage compressors up and down, as required, to maintain the VAV
Low SAT Setpoint.
CV SPECIFIC SEQUENCES
Cooling Operation
Thermostat Control
If a 7-wire thermostat (2 Cool/2Heat) controls the unit,
all zone temperature setpoint control is maintained at
the thermostat. With this operation, the unit remains
idle until it receives a stage call from the Thermostat. If
“G” is called from the thermostat, the Supply Fan will
start and all occupied functions (if equipped), i.e. ventilation, economizer, etc. will be allowed to operate.
Stage 1 (“Y1”) Call
If Y1 is called and the unit is equipped with an economizer, the control will check to see if the Outside Air is
suitable for economizing. If conditions are suitable for
economizing, the control will control the economizer and
stage up compressors, as required, to maintain a high

30

SAT setpoint. If conditions are not suitable for economizing or not equipped with an economizer, the control
will stage up 50% of the compressors. This shall be
maintained until Stage 1 is deactivated or Stage 2 is
called.
Stage 2 (“Y2”) Call
If Y2 is called and the unit is equipped with an economizer, the control will check to see if the Outside Air is
suitable for economizing. If conditions are suitable for
economizing, the control will control the economizer and
stage up compressors, as required, to maintain a LOW
SAT setpoint. If conditions are not suitable for economizing or not equipped with an economizer, the control
will stage up 100% of the compressors. This shall be
maintained until Stage 2 is deactivated.
Zone Sensor Control
If a zone sensor controls the unit, the OptiLogic™ controller shall maintain all zone temperature setpoints.
These setpoints are user selectable at the OptiLogic™
User Interface.
When a zone sensor is used for control, the OptiLogic™
unit controller will monitor the temperature within the
space and control the unit accordingly. A closed-loop
staging algorithm is used to stage compressors up and
down as required to maintain the desired zone temperature setpoint. If the unit is equipped with an economizer,
Outside Air conditions are continuously monitored by the
control to determine if conditions are suitable for economizing. If conditions are suitable for economizing, the
OptiLogic™ controller will modulate the Outside Air
damper in addition to staging compressors up and down
to maintain the zone temperature setpoint.

YORK INTERNATIONAL

FORM 100.50-EG1

Power Wiring
SINGLE-POINT POWER SUPPLY WIRING

Electrical / Controls Box
Control Side

GND

1L1
1L2
1L3

Power Side

TB1

Wiring Terminal
Block
LD06414

Field Power
Supply

Line 1
Line 2
Line 3

Earth
Ground

NOTES:
1. All field wiring must be provided through a field-supplied fused disconnect switch to the unit terminals (or optional molded
disconnect switch).
2. All electrical wiring must be made in accordance with all N.E.C. and/or local code requirements.
3. Minimum Circuit Ampacity (MCA) is based on U.L. Standard 1995, Section 36.14 (N.E.C. Section 440.34).
4. Maximum Dual Element Fuse size is based on U.L. Standard 1995, Section 36.15 (N.E.C. Section 440.22)
5. Use copper conductors only.
6. On units with an optional disconnect switch, the supplied disconnect switch is a “Disconnecting Means” as defined in the N.E.C. Section
100, and is intended for isolating the unit from the available power supply to perform maintenance and troubleshooting. This disconnect
switch is not intended to be a Load Break Device.

FIG. 2 – SINGLE-POINT POWER SUPPLY WIRING

YORK INTERNATIONAL

31

Power Wiring (continued)
SINGLE-POINT POWER SUPPLY WIRING
WITH NON-FUSED DISCONNECT
Electrical / Controls Box
Control Side

GND

Molded
Case
Disconnect
Switch

1L1
1L2
1L3

Power Side

Wiring Terminal
Block
LD06415

Field Power
Supply

Line 1
Line 2
Line 3
Earth
Ground

NOTES:
1. All field wiring must be provided through a field-supplied fused disconnect switch to the unit terminals (or optional molded
disconnect switch).
2. All electrical wiring must be made in accordance with all N.E.C. and/or local code requirements.
3. Minimum Circuit Ampacity (MCA) is based on U.L. Standard 1995, Section 36.14 (N.E.C. Section 440.34).
4. Maximum Dual Element Fuse size is based on U.L. Standard 1995, Section 36.15 (N.E.C. Section 440.22)
5. Use copper conductors only.
6. On units with an optional disconnect switch, the supplied disconnect switch is a “Disconnecting Means” as defined in the N.E.C. Section
100, and is intended for isolating the unit from the available power supply to perform maintenance and troubleshooting. This disconnect
switch is not intended to be a Load Break Device.

FIG. 3 – SINGLE-POINT POWER SUPPLY WIRING WITH NON-FUSED DISCONNECT

32

YORK INTERNATIONAL

FORM 100.50-EG1

DUAL-POINT POWER SUPPLY WIRING

Electrical / Controls Box
Control Side

Power Side

GND

1L1
1L2
1L3

TB1
GND

2L1
2L2
2L3

TB2

Wiring Terminal
Block
LD06416

Field Power
Supply #2

Field Power
Supply #1

Line 1
Line 2
Line 3
Earth
Ground
Line 1
Line 2
Line 3
Earth
Ground

NOTES:
1. All field wiring must be provided through a field-supplied fused disconnect switch to the unit terminals (or optional molded
disconnect switch).
2. All electrical wiring must be made in accordance with all N.E.C. and/or local code requirements.
3. Minimum Circuit Ampacity (MCA) is based on U.L. Standard 1995, Section 36.14 (N.E.C. Section 440.34).
4. Maximum Dual Element Fuse size is based on U.L. Standard 1995, Section 36.15 (N.E.C. Section 440.22)
5. Use copper conductors only.
6. On units with an optional disconnect switch, the supplied disconnect switch is a “Disconnecting Means” as defined in the N.E.C. Section
100, and is intended for isolating the unit from the available power supply to perform maintenance and troubleshooting. This disconnect
switch is not intended to be a Load Break Device.

FIG. 4 – DUAL-POINT POWER SUPPLY WIRING

YORK INTERNATIONAL

33

Field Control Wiring

SS+
SSSSA+
SSAIAQ+
IAQ-

G

COM
R (24 VAC)
Y1
Y2

1. Wiring shown indicates typical wiring.
2. All wiring is Class 2, low voltage.
3. Maximum power available from the 24 VAC
terminal is 40 VA.
4. Use shielded wire where shown.

R (24 VAC)
OCC
SD
SMK
HR
COM

Wiring Notes:

7 Wire Thermostat

SHIELD

SHIELD

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

COMMON
R (24VAC)
Y1 (Cool Stage 1)
Y2 (Cool Stage 2)
G (Fan)

Space Sensor
1K Nickel
RTD Sensor

Signal
Common

1.5K Adjust
Potentiometer

Signal
Common

* Use Shielded Wire
* Use Shielded Wire

CO 2 Sensor
0-5V Output

Signal
Common

* Use Shielded Wire

Note, 24VAC switch voltage must be
sourced from the unit. Use of another
power source external of the unit may
cause equipment damage.

Occupied /
Unoccupied Input
Shutdown Input
Smoke Purge Input

VAV Heat
Relay Output

Closed = Occupied
Open = Unoccupied

Closed = Shutdown
Open = Normal

Closed = Smoke Purge
Open = Normal

24 VAC Signal
Common
Note: VAV Heat Relay
output shall be used to
command the VAV boxes
to open full.

LD06158

FIG. 5 – FIELD CONTROL WIRING

34

YORK INTERNATIONAL

40"

5-3/4"

SECTION DESCRIPTIONS

35-3/4"

EE
FE
MB
_F
CC
FS
DP
CO
CP

36-7/8"

82-3/8"

41 3/16"

CONTROL PANEL DETAIL

A I R F L OW

CP

149-5/16"

83"

106-7/16"

31-7/8"

4-5/8"

46"

7-3/8"

6"

71-3/16"
9-1/4"

53"

28-5/8"

RETURN OPENING

SUPPLY OPENING

= Economizer
= Fan Exhaust
= Mixing Box
= Filter Segment
= Cooling Coils
= Supply Fan
= Discharge Plenum
= Condenser Section
= Control Panel

10'

CO
72"
FRONT

72"
REAR

72"
SIDE

72"
SIDE

General Arrangement Drawing

BOTTOM RETURN
BOTTOM SUPPLY

YORK INTERNATIONAL

TOP VIEW

179"
16-1/16"
24-5/16"

7-3/16"

SIDE VIEW
(LEFT SIDE)

3-9/16"

1-1/2" FPT

FRONT VIEW

COUPLING
DRAIN CONN.
(LEFT SIDE)

REAR VIEW

236-1/16"
95-1/4"
(SEE NOTE 6)
140-3/4"

92-3/16"

1-9/16"

379-9/16"

NOTES:
1. 10' CLEARANCE MINIMAL OVER THE TOP OF THE CONDENSING UNIT.
2. ONLY ONE ADJACENT WALL CAN EXCEED UNIT HEIGHT.
3. 12' CLEARANCE REQUIRED TO ADJACENT UNITS.
4. 8' SERVICE ACCESS RECOMMENDED ON ONE SIDE.
5. ECONOMIZER AND EXHAUST HOODS, WHERE APPLICABLE, ARE FOLDED
INSIDE UNIT FOR SHIPMENT.
6. DIM. IS TO OUTSIDE OF LIFTING LUGS

LD06417

FORM 100.50-EG1

35

FIG. 6 – GENERAL ARRANGEMENT DRAWING

344"

6"

TOP VIEW

9-1/4"

31-7/8"
36-7/8"

CONTROL PANEL DETAIL

82-3/8"

SECTION DESCRIPTIONS
EE
FE
MB
_F
CC
FS
DP
CO
CP

SUPPLY
OPENING

C

RETURN
OPENING

EE

74"

FRONT VIEW
16-1/16"

FL

30-11/16"

AI

= Economizer
= Fan Exhaust
= Mixing Box
= Filter Segment
= Cooling Coils
= Supply Fan
= Discharge Plenum
= Condenser Section
= Control Panel

FE

140-3/4"

YORK INTERNATIONAL

5-1/8"

95-1/4"
(SEE NOTE 6)

117-7/16"
28-1/2"

SIDE VIEW
(LEFT SIDE)

5-13/16"

24-5/16"

REAR VIEW
6-1/2"
79-1/8"

FIG. 7 – GENERAL ARRANGEMENT DRAWING

LD06418

General Arrangement Drawing (continued)

53"

REAR RETURN
LEFT OR RIGHT SUPPLY

36
NOTES:
1. 10' CLEARANCE MINIMAL OVER THE TOP OF THE CONDENSING UNIT.
2. ONLY ONE ADJACENT WALL CAN EXCEED UNIT HEIGHT.
3. 12' CLEARANCE REQUIRED TO ADJACENT UNITS.
4. 8' SERVICE ACCESS RECOMMENDED ON ONE SIDE.
5. ECONOMIZER AND EXHAUST HOODS, WHERE APPLICABLE, ARE FOLDED
INSIDE UNIT FOR SHIPMENT.

Curb Layout Drawing

YORK INTERNATIONAL
87"

RN

TU

RE

237"
339"

35-3/4"

51
71-3/5"
52"
LY

PP

SU

53-3/4"

40"

NOTES:

5. CURB INSULATED WITH 1.5"-3# INSULATION.

37

FIG. 8 – CURB LAYOUT DRAWING

LD06419

FORM 100.50-EG1

1. CURB, NAILER & GASKET ONLY, FURNISHED BY YORK. ALL
OTHER PARTS ARE FURNISHED AND INSTALLED "BY OTHERS".
2. ROOF CURB SHIPPED IN PIECES FOR FIELD ASSEMBLY.
3. ROOF CURB MUST BE INSTALLED SQUARE AND LEVEL.
4. CURB MATERIAL IS 14 GAUGE GALVANIZED, NOT PAINTED.

Guide Specifications
GENERAL
Units shall be designed for outdoor rooftop installation
on a roof curb. Units shall be rated according to ARI
360. Units shall be shipped in a single package, fully
charged with HFC-407C refrigerant. The manufacturing facility shall be registered under ISO 9001 Quality
Standards for Manufacturing. All units shall be completely factory assembled and run tested.
Units shall be ETL listed and be tested according to UL
1995. Tags and decals to aid in the service or indicate
caution areas shall be provided. Installation, operation
and maintenance manuals shall be supplied with each
unit.
Units shall be capable of providing mechanical cooling
down to 45° F (0°F with a low ambient kit). Unit shall be
capable of starting and running at 120° F. Unit electric
and gas connections shall be either through the curb or
the side of the unit.
CONSTRUCTION
Base
The base rail shall be constructed of 12 gauge galvanized steel, extending the full perimeter of the unit. All
components shall be supported from the base, and the
base shall include integral lifting lugs. The unit base
rail shall overhang the roof curb for water runoff and
shall have a fabricated recess with a continuous flat
surface to seat on the roof curb gasket, providing a
positive, weather tight seal between the unit and the
curb.
Casing
The unit cabinet shall be double wall construction to
provide both maximum resistance to bacterial growth
in the air stream and superior structural integrity. All
sheet metal shall be G90 mill galvanized sheet metal,
formed and reinforced to provide a rigid assembly. Cabinet shall be coated with baked on powder paint which,
when subject to ASTM B117, 500 hour, 5% salt spray
test, yields minimum ASTM 1654 rating of “6”. The unit
shall be insulated with 1-1/2,” 1 pound fiberglass insulation between the two sheet metal skins. Insulation shall
meet NFPA-90A regulations for smoke and flame
spread ratings. Single-wall units, or foil-faced insulation in the air stream shall be not acceptable.
The cabinet corner post and the intermediate side supports shall be a minimum of 16-gauge steel. All access

38

doors shall be a minimum of 18 gauge on the exterior
surfaces, and 20 gauge on the interior. Interior floor
panels shall be 18 gauge.
All serviceable sections shall have hinged access doors
with latches on both sides of the unit. All access doors
shall be constructed of 20-gauge steel on the outside,
with 24 gauge on the inside. Each door shall seal against
PVC gaskets to prevent air and water leakage.
The roof shall be double wall, with 18 gauge on the
external surface and 24 gauge on the interior. The roof
shall be formed with a 45 degree “drip lip” overhanging
the side walls to prevent precipitation drainage from
streaming down the side of the unit. Roof sections shall
be connected together via integral channels fastened
with screws and sealed with gasketing. Each fastened
seam shall be further protected by a sheet metal channel covering the full length of the gasket surface, making a completely water tight seal.
SUPPLY AIR SYSTEM
Supply Air Fan
Fans shall be centrifugal type, statically and dynamically balanced in the factory. Fan wheels shall be designed for continuous operation at the maximum rate
of fan speed and motor HP. Fans shall be double-width,
double-inlet with forward curved blades.
The fan and motor assembly shall be mounted on a
common base to allow consistent belt tension with no
relative motion between the fan and motor shafts. The
entire assembly shall be isolated from the unit base
with 1" deflection springs. The fan discharge shall be
connected to the cabinet through a reinforced neoprene
flexible connection to eliminate vibration transmission
from the fan to the unit casing.
BEARINGS AND DRIVES
Bearings shall be self-aligning pillow-block re-greasable
ball bearings with an average life expectancy L10 of
40,000 hours. Grease fittings shall be accessible
through access doors.
Fan motors shall be NEMA designed, Standard efficiency ball bearing type with electrical characteristics
and horsepower as specified. Motors shall be 1750
RPM, open drip proof type. The motor shall be located
within the unit on an adjustable, heavy steel base.

YORK INTERNATIONAL

FORM 100.50-EG1

All fan motor drives shall be selected for a minimum
service factor of 1.2 and have fixed pitched sheaves.
AIR FILTERING SYSTEM
All filter holding frames shall be of heavy-duty construction designed for industrial applications. All filters shall
be either side accessible via access doors on both sides
of the filter section.
All filter media shall be Class II listed under UL Standard 900. Filter efficiencies shall be rated in accordance
with ASHRAE Standard 52-76
Two-inch throwaway filters in an angled filter rack shall
be standard. On units with rigid filters, two-inch prefilters
shall be installed upstream of the rigid filters.
AIR INLET SYSTEM
General
A factory installed outside air rain hood permanently
attached to the cabinet to prevent windblown precipitation from entering the unit shall cover inlet openings.
The rain hoods on the sides of the unit shall be rotated
into the cabinet and secured for shipment so that upon
installation they need only be rotated upwards and
screwed into place. The outside air hood shall contain
a removable and cleanable filter.
All damper assemblies shall be of low leak design.
Damper blades shall be fabricated from a minimum of
16 gauge galvanized steel.
REFRIGERATION SYSTEM
Units shall have four compressors for maximum loadmatching capability. Each refrigerant circuit shall be
controlled with a thermal expansion valve for maximum
control at low load conditions.
Evaporator Coils
Evaporator coils shall be direct expansion. Coil tubes
shall be 3/8” OD copper, with internally enhanced tubes.
Fins shall be enhanced aluminum mechanically expanded to bond with the copper tubes. Coil casing shall
be fabricated from heavy gauge galvanized steel.
A stainless steel double-sloped drain pan shall be provided under the entire width of the evaporator coil, including all return bends. The main drain pan shall be
sloped a total of 1/4” per foot towards the drainage point
according to ASHRAE 62 guidelines. Main drain pan
shall be accessible and cleanable in the field. The conYORK INTERNATIONAL

densate drain opening shall be flush with the bottom of
the drain pan to allow complete drainage. Coils in excess of 48” high shall have an intermediate drain pan,
extending the entire width of the coil to provide better
water drainage.
Compressors
Compressors shall be hermetic, scroll-type, including
tip seals to provide efficient axial sealing while preventing scroll tip to base contact, controlled orbit design for
radial sealing to incorporate minimum flank-to-flank contact for long service life, refrigerant cooled motors, large
suction side free volume and oil sump to provide liquid
handling capability, annular discharge check valve and
reverse vent assembly to provide low pressure drop,
silent shutdown and reverse rotation protection, initial
oil charge, oil level sight glass, vibration isolator mounts
for compressors, and brazed-type connections for fully
hermetic refrigerant circuits.
Condenser Coils
Condenser coils shall have 3/8” seamless copper tubes,
arranged in staggered rows, mechanically expanded into
aluminum fins. Coils shall be protected from hail damage with a “V” configuration, with individual flat coils rotated from the vertical plane for each condensing circuit.
Condenser Fans and Motors
Condenser fans shall be direct drive, propeller type,
discharging vertically. Condenser fan motors shall be
3-phase, totally enclosed air over (TEAO). Thermal
overload protection shall be provided for each condenser fan motor.
Refrigerant Piping
All interconnecting piping between refrigeration components shall be copper tubing with brazed joints.
Each refrigerant circuit shall be equipped with liquid line
filter drier, and moisture indicating sight glass. Each
circuit shall also have both high and low pressure
switches installed on either side of the compressor and
include access fittings for replacement of the pressure
switches without removing charge.
Polyurethane sleeves shall protect all small diameter
distributor tubing to the evaporator coil to prevent the
tubes from copper-to-copper contact during shipment
or operation.
POWER SUPPLY
Unit power supply shall be 460V 3-phase 60Hz (208,
230 and 575V optional) single-point power connections
with terminal block connections.
39

Guide Specifications (continued)
CONTROLS

ACCESSORIES AND OPTIONS

A factory-mounted unit controller with a 4x20 character
alphanumeric display and user keypad shall be included
as standard. The controller and keypad shall be housed
inside the low-voltage compartment of the control/power
panel. On units with supply or exhaust VFDs, the VFD
keypads shall be located inside the same panel as the
unit controller and interface keypad. Control operating
data, setpoints, unit setup, configuration, service and
history shall all be accessible via a single key. A system alarm LED shall indicate failures to the operator
with more detail provide in the menu screens. The user
interface shall function with a simple menu-driven display for easy access to unit data with integral time clock
for weekly and holiday scheduling. The unit keypad
shall include password protection to prevent unauthorized access and tampering with unit setpoints and configuration.

Full perimeter and partial perimeter roof curbs - 14”
high roof curb with wood nailer. Roof curb covers the
entire perimeter of the unit (full curb) or that portion of
the unit that has airflow (partial curb).

A single terminal strip shall be provided for all thermostat and customer hard-wired field connections.
Unit controls shall be completely factory packaged and
compatible with a room thermostat. Constant volume
units shall operate with a two (2) cool/two (2) heat thermostat. Staging decisions shall be based upon the deviation of space temperature from set point and the rate
of change of the space temperature.
VAV units shall operate with a sensor in the supply air
stream for cooling operation. Staging decisions shall
be based upon the deviation of supply air temperature
from set point and the rate of change of the supply air
temperature.
Controllers shall have the following safeties (both VAV
and CV):
• High and low pressure cut-outs (one each refrigerant circuit)
• Minimum on time for compressors
• Delay between compressor stages
• Anti-short cycle delays (minimum off time) for compressors and supply fan
• Cooling lockout at 40° F; 0° F if equipped for low
ambient operation
• Air flow proving switch requiring proper air flow for
cooling operation

40

Supply Fan VFD Manual Bypass – provides full airflow in the event of a VFD failure.
Power Supply Connections – single-point power with
manual disconnect, and dual-point power wiring options
are available for various applications.
Supply air setpoint reset by outside air or space air
temperature - Allows VAV supply air setpoint to float
upward (saving energy) if the outdoor air temperature
or the space temperature is sufficiently low.
Supply Fan Isolation – the entire supply fan assembly shall be isolated from the unit base with 2" deflection springs.
Supply and Exhaust Fan Motors – high efficiency
ODP, and standard and high efficiency TEFC motors
are available all meeting the Energy Policy Act of 1992
(EPACT).
Low Ambient Operation – a low ambient kit is available to control compressor head pressure via VFD condenser fan speed control. Head pressure control is
accomplished by monitoring head pressure with suction and discharge line pressure transducers rather than
less accurate temperature control.
ECONOMIZERS
Manual Damper Economizer – economizer is available with a manual damper adjustable between 0-25
percent.
Two-Position Damper Economizer – economizer is
available with a two-position damper with the open position adjustable between 0-25 percent. The operation
of the two-position economizer shall be based on occupancy; occupied is open, unoccupied is closed.

YORK INTERNATIONAL

FORM 100.50-EG1

Modulating Damper Economizer – economizer is
available with a modulating damper arrangements.
Modulating damper economizers shall have outdoor air
and return air dampers that are interlocked and positioned by fully modulating, solid state damper actuators. The actuators shall be spring loaded so that the
outside air damper will close when power to the unit is
interrupted. The operation of the modulating economizer
shall be fully integrated into the cooling control system.
The modulating economizer control shall be via a dry
bulb sensor, single or dual enthalpy sensors.
Airflow Measurement – airflow measurement is available for the Modulating Damper Economizer option
listed above. Three options exist for airflow measurement; minimum airflow and 100% air flow. Minimum
airflow measures airflow between 0 and the minimum
ventilation airflow up to 25% outside air. 100% airflow
measurement measures air flow from 0-100% of the
outside airflow.
RELIEF SYSTEM
Barometric Relief - building air exhaust shall be accomplished through barometric relief dampers installed
in the return air plenum. The dampers will open relative
to the building pressure.
Exhaust Air Fans - two (2) forward curved centrifugal
fans shall be installed in the return air plenum for positive power exhaust. Fan impellers shall be on a common shaft, driven by a single motor. The fans, motors
and drives shall be of the same quality and design as
specified for the supply air fan, except the fans shall be
Class I. Exhaust control options are on/off, modulating
discharge damper, or VFD fan speed control. On units
with non-modulating exhaust a barometric relief damper
is included to prevent outside air from entering in the
off cycle. Fans shall cycle on and off with building pressure. On units with modulating exhaust and two position control based on building pressure, a field-installed
static pressure sensor mounted in the conditioned
space or return air duct is required for damper and VFD
modulation.

YORK INTERNATIONAL

EVAPORATOR COIL PROTECTION
Copper Fins – provided in lieu of aluminum fins.
Pre-Coated Fins – an epoxy-coated aluminum fin stock
to guard from corrosive agents and insulate against galvanic potential. Used for mild seashore or industrial
locations.
CONDENSER COIL PROTECTION
Copper Fins – provided in lieu of aluminum fins.
Pre-Coated Fins – an epoxy-coated aluminum fin stock
to guard from corrosive agents and insulate against galvanic potential. Used for mild seashore or industrial
locations.
Post-Coated Fins – Technicoat coil-coating process
used on condenser coils for seashore and other corrosive applications (with the exception of strong alkalis,
oxidizers, wet bromide, chlorine and fluorine in concentrations greater than 100ppm).
Hot Gas Bypass (Optional on Constant Volume;
Standard on VAV) – permits continuous, stable operation at capacities below the minimum step of unloading
by introducing an artificial load on the evaporator.
BACNet Communications Card – for BAS communications, a BACNet card is available with Ethernet
connection.
Compressor Sound Blankets – compressor acoustic
sound blankets for sound sensitive applications.
CO2 Sensors – carbon dioxide sensors for occupied
space that operate demand ventilation control opening
outside air dampers to ventilate building.
Suction and Discharge Pressure Transducers – monitor and readout of suction and discharge pressures.

41

NOTES

42

YORK INTERNATIONAL

FORM 100.50-EG1

NOTES

YORK INTERNATIONAL

43

Proud Sponsor
of the 2002
U.S. Olympic Team
36USC380
P.O. Box 1592, York, Pennsylvania USA 17405-1592
Copyright © by York International Corporation 2001
Form 100.50-EG1 (201)
New Release

Tele. 800-861-1001
www.york.com

Subject to change without notice. Printed in USA
ALL RIGHTS RESERVED



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Subject                         : Form 100.50-EG1(201), eco2 Packaged Rooftop Air Conditioning Units, Engineering Guide
Keywords                        : Form 100.50-EG1(201), eco2 Packaged Rooftop Air Conditioning Units, Engineering Guide
Author                          : Visual Impact Productions, Inc.
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Title                           : Form 100.50-EG1(201), eco2 Packaged Rooftop Air Conditioning Units, Engineering Guide
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