Carrier Base 50ZPA Operation manual

50ZPA SINGLE PACKAGED
AIR CONDITIONERS
2 to 5 Tons
IN
50ZPA SINGLE-PACKAGED
AIR CONDITIONERS
2 to 5 Tons
Product Data
The 50ZPA unit is a packaged air conditioner
for manufactured housing, residential, and light
commercial applications. The 50ZPA unit
design is the result of our firm commitment to
the development of the finest air conditioners
that modern technology can offer.
The 50ZPA unit is built in one basic cabinet size
and features a round side-by-side duct
configuration on sizes 024-048. Rectangular
duct configuration is provided on the 060 size
only.
Features/Benefits
FACTORY-ASSEMBLED PACKAGE is a
compact, fully self-contained, electric cooling
unit with horizontal supply and return ducts.
The 50ZPA units are available in a variety of
standard cooling sizes with voltage options to
meet residential and light commercial
requirements. Unit installs easily on a ground-
level pad.
EASY TO INSTALL 50ZPA units are small,
compact, and easy to handle. Every 50ZPA unit
has an identical 32 x 51-in. footprint to make
planning simple. The concise design uses less
sheet metal and makes the 50ZPA units lighter
than other units. The unit can be easily
positioned on the jobsite with the hand holds
built into the unit basepan. Drop-in cartridge
style heaters are utilized to minimize
installation time. The 50ZPA unit was designed
with potential safety hazards in mind; with no
sharp edges or corners which could injure a
worker.
NEW AND IMPROVED AERODYNAMIC
FAN BLADE DESIGN
reduces the overall
sound by up to 3dB; now as low as 77dB.
SERVICE ACCESS makes installation and
maintenance quicker and easier. The 50ZPA
units are designed to be serviced from both the
side and rear. The new design allows easy access
for installation and maintenance procedures on
the unit. Routine maintenance tasks such as coil
cleaning are sped up with the new multiple
access side panels.
NO-RUST BASEPAN WITH
INTEGRATED DRAIN PAN
is standard on
all units. The 50ZPA units feature a tough, high-
tech, composite material basepan with
integrated drain pan. The composite material
eliminates the potential problems of rust and
premature replacement which are common with
standard metal basepans.
DURABLE PRE-PAINTED STEEL
CABINET
protects against harsh weather. The
watertight construction and corrosion- resistant
UNIT 50ZPA

2
50ZPA
finish of the 50ZPA unit will keep it looking like
new for years. The paint treatment process
ensures quality protection against the elements.
A compact, low-profile design utilizes a
louvered coil enclosure for protection against
vandalism and hail damage.
INDOOR AIR QUALITY is designed into the
50ZPA units. A sloped drain pan minimizes the
amount of standing water inside the unit, which
limits mold and mildew growth. The drain pan
is made of a rust-proof material and will not
deteriorate or release foreign matter into the
airstream.
LIGHTWEIGHT, COMPACT
CONSTRUCTION
is ideal for manufactured
housing and residential applications. The
50ZPA unit is one of the lightest, most compact
packaged units ever designed. It’s light weight
(293 lbs for the 50ZPA024 unit) makes the unit
easier to handle. The low height keeps ductwork
connections to a minimum and makes units less
visible.
The 50ZPA units utilize a structural beam
design to form the four sides of the cabinet.
Only 12 different pieces of sheet metal are used
in the unit construction to simplify the unit for
greater reliability.
EFFICIENT, DEPENDABLE
PERFORMANCE
with durable compressors
designed for efficiency. The 50ZPA units offer
13.0 SEER (Seasonal Energy Efficiency Ratio)
cooling performance efficiencies. This
performance level can reduce cooling expenses
by as much as 25% compared to older cooling
equipment. A high-eficiency, multi-speed
blower motor system ensures quality
performance with most duct systems. The
computer-designed blower wheel is balanced
for quiet operation.
DURABLE, DEPENDABLE,
COMPRESSORS
are designed for high
efficiency. Each compressor is hermetically
sealed against contamination to help promote
longer life and dependable operation. Vibration
isolation provides quiet operation. Compressors
have internal high-pressure and overcurrent
protection.
DIRECT-DRIVE MULTISPEED, PSC
(PERMANENT SPLIT CAPACITOR)
BLOWER MOTOR
is standard on all models.
Direct-drive, PSC condenser-fan motors are
designed to help reduce energy consumption
and provide for cooling operation down to 40°F.
REFRIGERANT SYSTEM is designed to
provide dependability. Liquid refrigerant
strainers are used to promote clean, unrestricted
operation. Each unit leaves the factory with a
full refrigerant charge. Refrigerant service
connections make checking operating pressures
easier.
ACCESSORY ELECTRIC HEATERS — A
variety of accessory electric heaters are
available for the 50ZPA units. These heaters are
comprised of a separate heater module mounted
on the blower inlet and remote mounted controls
located in the unit control box. Single point
electrical connections are available for
powering both the heater and the unit.
Corporate Thermostat — These provide
cooling control for unit. Autochangeover and
manual changeover types are available.
The MotorMaster II Low Ambient Kit — Kit
permits operation down to 0° F. Use when
mechanical cooling is required when outdoor-
air temperature is between 40°F and 0°F.
Crankcase Heater — Warms crankcase oil to
reduce refrigerant migration and ensure proper
compressor lubrication. For use in applications
where crankcase is subjected to low outside
temperatures. Recommended on 208/230-1-60,
size 024-042 units only.
Solid-State Time Guard
®
Device — Package
consists of a control to be field-wired into the
unit controls, and provides a 5-minute delay in
compressor operation between cooling cycles.
Prevents compressor short cycling when rapid
compressor cycles may be a problem.
Controls Upgrade Kit — Contains high- and
low-pressure switches to protect the unit from
running at unsuitable pressures. Provides
additional safety features when needed.
Outdoor Thermostat — Accessory provides
control when outdoor-air temperature falls
below set point. Helps to bring second stage of
2-stage electric heater on line.
Table of contents
Page
Features/Benefits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
ARI Capacity Ratings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Model Nomenclature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Physical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Dimensional Drawings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6
Selection Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Performance Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-11
Typical Wiring Schematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-15
Electrical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Operating Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Typical Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Application Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Engineers’ Specification Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
ARI* capacity ratings
UNIT 50ZPA
(SERIES)
NOMINAL
TONS
STANDARD
CFM
NET COOLING CAPACITIES
AT 95°F (Btuh)† SEER**
SOUND
RATINGS†† (dB)
024 2.0 800 24,000 13.0 77
030 2.5 1000 29,000 13.0 81
036 3.0 1200 36,000 13.0 81
042 3.5 1400 40,000 13.0 81
048 4.0 1600 45,000 13.0 81
060 5.0 1900 52,000 13.0 83
LEGEND
db — Dry Bulb
dB — decibels
SEER — Seasonal Energy Efficiency Ratio
wb — Wet Bulb
* Air Conditioning & Refrigeration Institute.
† Rated in accordance with U.S. Government DOE Department of
Energy) test procedures and/or ARI Standard 210/240-89.
** All units have factory-installed time-delay relay.
†† Rated in accordance with ARI Standard 270-84.
NOTES:
1. Ratings are net values, reflecting the effects of circulating fan heat.
2. Cooling capacity ratings are based on cooling standard:
80°F db/67°F wb indoor air entering temperature
95°F db air entering outdoor unit
M
A
N
U
F
A
C
T
U
R
E
R
C
E
R
T
I
F
I
E
D
T
O
A
R
I
A
S
C
O
M
P
L
Y
I
N
G
W
I
T
H
A
R
I
S
T
A
N
D
A
R
D
2
1
0
U
N
I
T
A
R
Y
A
I
R
C
O
N
D
I
T
I
O
N
I
N
G
E
Q
U
I
P
M
E
N
T
REGISTERED
ISO 9001:2000

3
50ZPA
Physical data
* Required filter sizes shown are based on the ARI (Air Conditioning and and Refrigeration Institute) rated airflow at a velocity of
300 ft/min for throwaway type or 450 ft/min for high capacity type. Recommended filters are 1-in thick.
UNIT SIZE 024 030 036 042 048 060
NOMINAL CAPACITY (ton)
2 2-1/2 3 3-1/2 4 5
OPERATING WEIGHT (lb.) 268 299 352 364 359 408
Compressor Scroll Ultra Tech Scroll
Refrigerant (R-22)
6.8 9.5 9.5 11.1 10.7 12.5
Quantity (lb.)
REFRIGERANT METERING DEVICE
Accurater TXV
Orifice ID (in.) 0.067 0.067 0.082 0.086 — —
CONDENSER COIL Copper Tubes, Aluminum Plate Fins
Rows…Fins/in. 2…21 2…21 2…21 2…21 2…21 2…21
Face Area (sq. ft.) 11.1 12.7 15.8 15.8 13.3 15.8
CONDENSER FAN Propeller
Nominal Cfm 2600 2600 3200 3200 3200 3300
Diameter 20 20 20 20 20 20
Motor HP (RPM) 1/8 (825) 1/8 (825) 1/4 (1100) 1/4 (1100) 1/4 (1100) 1/2 (1100)
EVAPORATOR COIL Copper Tubes, Aluminum Plate Fins
Rows…Fins/in. 3…17 3…17 4…17 4…17 4…17 4…17
Face Area (sq. ft.) 4.3 4.9 4.9 6.1 4.9 6.1
Evaporator blower Direct Drive
Nominal Airflow (Cfm) 800 1000 1200 1400 1600 1875
Size (in.) 10x8 10x8 11x9 11x9 11x10 11x10
Motor HP (RPM) 1/2 (1050) 1/2 (1050) 3/4 (1050) 3/4 (1050) 1 (1050) 1 (1050)
CONNECTING DUCT SIZES Round
Supply Air (in.) 14
Return Air (in.) 14
Return-Air Filters (in.)*
24 x 24 24 x 24 24 x 24 30 x 30 30 x 30 30 x 30
Throwaway
TT
MODEL NUMBER NOMENCLATURE
50ZPA 3 X 024
Model No.
50ZPA — Single Package
--------- -Heat Pump Unit
Electrical Supply
3 — 208/230-1-60
N/A
Nominal Cooling Capacity
024 – 2 Tons
030 – 2-1/2 Tons
036 – 3 Tons
042 – 3-1/2 Tons
048 – 4 Tons
060 – 5 Tons
––– A A
Series
A — Original
Brand Name
A — Common Unit
N/A

4
50ZPA
Dimensional drawings — 50ZPA024-060
UNIT
50ZPA
ELECTRICAL
CHARACTERISTICS
UNIT WEIGHT CENTER OF GRAVITY
in. [mm]
lb kg X Y Z
50ZPA024 208/230-1-60 268 122 30.13 (765) 14.0 (356) 19.0 (483)
50ZPA030 208/230-1-60 299 136 34.13 (867) 14.0 (356) 19.0 (483)
50ZPA036 208/230-1-60 352 160 42.13 (1070) 14.0 (356) 19.0 (483)
50ZPA042 208/230-1-60 364 165 42.13 (1070) 14.0 (356) 19.0 (483)
50ZPA048 208/230-1-60 359 163 42.13 (1070) 14.0 (356) 19.0 (483)
50ZPA060 208/230-1-60 408 185 42.13 (1070) 14.0 (356) 19.0 (483)

5
50ZPA
Selection Procedure
I DETERMINE COOLING AND HEATING
REQUIREMENTS AT DESIGN CONDITIONS.
Given:
Required Cooling Capacity (TC) . . . . . . . . . . 34,000 Btuh
Sensible Heat Capacity (SHC) . . . . . . . . . . . . 25,000 Btuh
Required Heating Capacity. . . . . . . . . . . . . . . 15,000 Btuh
Outdoor Entering-Air Temperature . . . . . . . . . . . . . .95°F
Indoor Entering-Air Temperature. . . .80°F edb; 67°F ewb
Indoor-Air Quantity . . . . . . . . . . . . . . . . . . . . . . 1200 cfm
External Static Pressure . . . . . . . . . . . . . . . . . .0.20 in. wg
Electrical Characteristics (V-Ph-Hz) . . . . . . . . . 230-1-60
II SELECT UNIT BASED ON REQUIRED COOLING
CAPACITY.
Enter Cooling Capacities table at condenser entering
temperature of 95°F, indoor air entering at 1200 cfm and
67°F ewb. The 50ZPA036 unit provides a total cooling
capacity of 34,200 Btuh and a sensible heat capacity of
25,300 Btuh.
For indoor-air temperature other than 80°F edb, calculate
sensible heat capacity correction, as required, using the
formula found in Note 3 following the Cooling Capacities
tables.
NOTE: Unit ratings are net capacities.
III SELECT ELECTRIC HEAT.
The required heating capacity is 15,000 Btuh (given).
Determine the electric heat capacity in kW.
15,000 Btuh
3414 Btuh/kW
Enter the Accessory Electric Heater table on page 18 for
208/230, single-phase, 50ZPA036 unit. The 5-kW heater at
240v most closely satisfies the heating required. To
calculate kW at 230 V, multiply the heater kW by
multiplication factor 0.92 found in the Multiplication
Factors table on page 18.
5 kW x 0.92 = 4.6 kW
4.6 kW x 3414 Btuh/kW = 15,704 Btuh
IV DETERMINE FAN SPEED AND POWER
REQUIREMENTS AT DESIGN CONDITIONS.
Before entering the air delivery tables, calculate the total
static pressure required. From the given, Filter Pressure
Drop table, the Accessory Electric Heat Pressure Drop
table, and the Wet Coil Pressure Drop table, find:
External static pressure 0.20 in. wg
Filter 0.10 in. wg
Electric Heat 0.13 in. wg
Wet Coil 0.09 in. wg
Total static pressure 0.52 in. wg
Enter the table for Dry Coil Air Delivery — Horizontal
Discharge. At 0.5 in. wg external static pressure and high
speed, the motor delivers 1297 cfm. Interpolating for 0.52
in. wg delivers 1276 cfm, which satisfies the job
requirements.
= 3.8 kW of heat required

6
50ZPA
Cooling capacities
See Legend and Notes on page 9.
50ZPA024
Temp (F) Outdoor Air
Entering Condenser
Evaporator Air - CFM/BF
700/0.08 800/0.010 900/.11
Evaporator Air - Ewb (F)
57 62 63* 67 72 57 62 63* 67 72 57 62 63* 67 72
75
TC 22.1 23.0 23.5 25.2 26.5 23.3 23.8 24.1 25.5 26.6 24.3 24.3 24.4 25.8 27.4
SHC 22.1 21.1 17.1 17.7 13.7 23.3 22.9 18.3 18.8 14.1 24.3 24.1 19.5 19.8 14.6
kW 1.7 1.7 1.7 1.7 1.7 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.9 1.9
85
TC 21.3 22.0 22.5 24.5 26.3 22.5 22.7 23.1 25.1 26.4 23.5 23.5 23.7 25.5 27.1
SHC 21.3 20.6 16.6 17.4 13.8 22.5 22.4 17.9 18.7 14.5 23.5 23.3 19.1 19.9 15.1
kW 1.9 1.9 1.9 1.9 1.9 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.1
95
TC 20.5 20.9 21.4 23.4 26.0 21.6 21.6 22.0 24.0 26.1 22.6 22.6 22.5 24.5 26.8
SHC 20.7 20.1 16.1 16.9 13.6 21.6 21.5 17.4 18.2 14.4 22.6 22.5 18.6 19.5 15.1
kW 2.1 2.1 2.1 2.1 2.1 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.3 2.3
105
TC 19.6 19.8 20.2 22.1 24.9 20.7 20.7 20.8 22.7 25.5 21.6 21.6 21.2 23.2 26.0
SHC 19.6 19.5 15.6 16.4 13.2 20.7 20.5 16.8 17.7 14.1 21.6 21.5 18.1 19.0 14.9
kW 2.3 2.3 2.3 2.3 2.4 2.4 2.4 2.4 2.4 2.4 2.5 2.5 2.5 2.5 2.5
115
TC 18.6 18.7 19.0 20.9 23.6 19.6 19.7 19.5 21.4 24.2 20.5 20.5 19.9 21.9 24.6
SHC 18.6 18.6 15.0 15.8 12.7 19.6 19.4 16.3 17.2 13.6 20.5 20.4 17.5 18.5 14.4
kW 2.5 2.5 2.5 2.6 2.6 2.6 2.6 2.6 2.6 2.7 2.7 2.7 2.7 2.7 2.8
125
TC 17.5 17.6 17.6 19.4 22.1 18.5 18.6 18.0 20.0 22.7 19.4 19.4 18.4 20.4 23.1
SHC 17.5 17.4 14.4 15.3 12.1 18.5 18.5 15.7 16.6 13.0 19.4 19.3 16.9 17.9 13.9
kW 2.8 2.8 2.8 2.8 2.9 2.9 2.9 2.9 2.9 2.9 3.0 3.0 3.0 3.0 3.0
50ZPA030
Temp (F) Outdoor Air
Entering Condenser
Evaporator Air - CFM/BF
875/0.08 1000/0.09 1125/0.10
Evaporator Air - Ewb (F)
57 62 63* 67 72 57 62 63* 67 72 57 62 63* 67 72
75
TC 27.0 28.2 28.9 30.7 32.0 28.7 29.1 29.5 31.1 32.9 29.9 29.9 29.9 31.3 33.1
SHC 26.7 25.6 20.7 21.4 16.2 28.4 27.9 22.2 22.9 16.2 29.5 29.5 23.7 24.3 16.2
kW 2.1 2.1 2.1 2.1 2.1 2.2 2.2 2.2 2.2 2.2 2.3 2.3 2.3 2.3 2.3
85
TC 25.7 26.4 27.1 30.0 32.4 27.3 27.4 28.0 30.7 32.7 28.7 28.8 28.8 31.2 32.9
SHC 25.4 24.8 20.0 21.1 16.7 27.0 27.0 21.6 22.7 17.6 28.4 28.5 23.2 24.3 18.5
kW 2.3 2.3 2.3 2.3 2.3 2.4 2.4 2.4 2.4 2.4 2.5 2.5 2.5 2.5 2.5
95
TC 24.5 24.8 25.4 28.1 31.7 25.9 26.0 26.2 29.0 32.3 27.2 27.3 26.9 29.7 32.6
SHC 24.2 24.0 19.2 20.3 16.5 25.6 25.7 20.8 22.0 17.5 26.9 27.0 22.4 23.7 18.4
kW 2.5 2.5 2.5 2.6 2.6 2.6 2.6 2.6 2.6 2.6 2.7 2.7 2.7 2.7 2.7
105
TC 23.2 23.3 23.7 26.3 30.0 24.6 24.7 24.5 27.1 30.9 25.8 25.8 25.0 27.7 31.6
SHC 23.0 23.0 18.5 19.6 15.8 24.3 24.4 20.1 21.3 17.0 25.5 25.5 21.6 22.9 18.0
kW 2.8 2.8 2.8 2.8 2.8 2.8 2.8 2.8 2.9 2.9 2.9 2.9 2.9 3.0 3.0
115
TC 21.8 21.9 21.9 24.4 28.0 23.2 23.3 22.6 25.1 28.9 24.3 24.4 23.1 25.7 29.5
SHC 21.6 21.6 17.7 18.8 15.1 22.9 23.0 19.3 20.5 16.2 24.0 24.1 20.8 22.1 17.3
kW 3.0 3.0 3.0 3.1 3.1 3.1 3.1 3.1 3.1 3.2 3.2 3.2 3.2 3.2 3.3
125
TC 20.3 20.4 19.8 22.5 26.0 21.6 21.7 20.4 23.2 26.7 22.8 22.8 20.9 23.7 27.3
SHC 20.1 20.2 16.9 18.1 14.4 21.4 21.4 18.4 19.8 15.5 22.5 22.6 19.9 21.4 16.6
kW 3.3 3.3 3.3 3.3 3.4 3.4 3.4 3.4 3.4 3.5 3.5 3.5 3.5 3.5 3.6

7
50ZPA
Cooling capacities (cont)
See Legend and Notes on page 9.
50ZPA036
Temp (F) Outdoor Air
Entering Condenser
Evaporator Air - CFM/BF
1050/0.07 1200/0.08 1350/0.10
Evaporator Air - Ewb (F)
57 62 63* 67 72 57 62 63* 67 72 57 62 63* 67 72
75
TC 33.1 35.1 35.8 38.8 40.9 33.7 36.2 36.8 39.6 41.5 33.7 37.3 37.5 40.0 41.8
SHC 33.1 31.9 25.8 26.9 22.5 36.3 34.5 27.7 28.7 21.6 36.3 36.7 29.5 30.2 22.3
kW 2.6 2.6 2.6 2.7 2.6 2.7 2.7 2.7 2.7 2.8 2.7 2.8 2.8 2.8 2.8
85
TC 32.5 33.3 34.0 37.1 40.5 32.7 34.4 34.9 38.1 40.9 33.4 35.7 35.6 38.9 41.4
SHC 32.5 31.0 24.9 26.2 21.0 32.7 33.5 26.8 28.2 22.0 33.4 35.1 28.6 30.1 22.9
kW 2.9 2.9 2.9 2.9 2.9 2.9 3.0 3.0 3.0 3.0 3.0 3.1 3.1 3.1 3.1
95
TC 31.2 31.5 32.1 35.1 39.4 31.4 32.7 32.9 36.0 40.3 32.3 34.0 33.5 36.7 40.9
SHC 31.2 30.1 24.1 25.3 20.4 31.4 32.2 25.9 27.4 21.7 32.3 33.5 27.7 29.3 22.8
kW 3.2 3.2 3.2 3.2 3.2 3.3 3.2 3.2 3.3 3.3 3.4 3.3 3.3 3.4 3.4
105
TC 29.4 29.6 30.1 33.0 37.2 30.1 31.1 30.8 33.8 38.1 30.4 32.3 31.4 34.4 38.8
SHC 29.4 29.1 23.2 24.5 19.6 30.1 30.6 25.1 26.5 20.9 30.4 31.8 26.8 28.3 22.1
kW 3.5 3.5 3.5 3.5 3.5 3.6 3.5 3.5 3.6 3.6 3.7 3.6 3.6 3.7 3.7
115
TC 28.4 29.3 29.4 32.4 34.8 28.7 29.4 28.7 31.5 35.6 29.4 30.5 29.3 32.1 36.3
SHC 28.4 29.1 24.1 25.5 18.7 28.7 28.9 24.2 25.6 20.0 29.4 30.1 25.9 27.4 21.2
kW 3.9 3.8 3.8 3.9 3.9 4.0 3.9 3.9 3.9 3.9 4.1 4.0 3.9 4.0 4.0
125
TC 28.0 29.1 28.7 31.8 32.4 28.3 27.4 29.0 30.7 33.1 28.2 28.7 29.2 29.8 33.7
SHC 28.0 28.6 23.0 24.4 17.8 28.3 26.9 26.8 26.6 19.1 28.2 28.2 28.7 26.5 20.3
kW 4.3 4.2 4.2 4.2 4.2 4.4 4.2 4.3 4.3 4.3 4.5 4.3 4.3 4.3 4.4
50ZPA042
Temp (F) Outdoor Air
Entering Condenser
Evaporator Air - CFM/BF
1225/0.11 1400/0.12 1575/0.14
Evaporator Air - Ewb (F)
57 62 63* 67 72 57 62 63* 67 72 57 62 63* 67 72
75
TC 37.9 38.8 40.2 40.9 43.7 37.7 40.3 39.6 43.6 43.9 37.6 40.1 40.2 42.5 44.7
SHC 37.9 38.6 28.9 28.9 22.2 45.9 40.1 30.3 32.0 23.4 45.7 38.0 31.5 32.7 24.5
kW 3.0 3.3 3.3 3.2 3.6 3.1 3.3 3.3 3.3 3.3 3.4 3.4 3.5 3.4 3.4
85
TC 36.1 36.7 38.5 40.1 42.7 37.2 38.6 39.0 40.6 43.6 37.4 39.8 39.6 42.2 44.6
SHC 36.1 36.5 28.2 28.6 22.4 37.2 38.3 30.1 30.8 23.8 37.4 39.6 32.1 33.3 25.3
kW 3.4 3.4 3.4 3.4 3.6 3.4 3.5 3.5 3.6 3.5 3.6 3.6 3.6 3.6 3.6
95
TC 35.1 35.9 36.7 39.3 42.2 36.6 37.2 37.4 40.0 42.4 37.0 38.1 36.5 40.5 42.8
SHC 35.1 35.7 27.3 28.3 22.2 36.6 37.1 29.4 30.5 23.4 37.0 37.9 30.5 32.6 24.6
kW 3.7 3.7 3.7 3.7 3.7 3.8 3.8 3.8 3.8 3.8 3.8 3.8 3.8 3.9 3.9
105
TC 32.8 33.9 34.3 36.8 39.3 34.8 35.2 34.9 37.4 39.7 33.9 34.1 33.4 36.0 39.9
SHC 32.8 33.7 26.3 27.3 21.1 34.8 35.0 28.3 29.5 22.1 33.9 33.9 28.9 30.3 22.7
kW 4.1 4.0 4.0 4.0 4.0 4.0 4.0 4.0 4.1 4.1 4.1 4.1 4.1 4.1 4.2
115
TC 31.3 32.2 32.3 34.8 36.0 31.3 31.7 31.3 33.7 37.6 32.1 32.7 30.5 32.7 36.6
SHC 31.3 32.1 25.4 26.5 19.2 31.3 31.5 26.6 27.8 21.6 32.1 32.5 30.7 33.0 22.5
kW 4.5 4.3 4.3 4.4 4.3 4.6 4.7 4.4 4.4 4.5 4.8 4.8 4.8 4.8 4.9
125
TC 28.0 28.6 27.4 31.3 33.0 28.2 28.8 27.6 30.0 32.9 29.0 29.7 27.9 30.6 32.8
SHC 28.0 28.5 24.7 25.1 19.5 28.2 28.6 24.9 26.1 19.4 29.0 29.5 27.2 28.0 18.1
kW 5.0 4.9 4.9 4.8 5.1 4.7 4.7 4.7 4.8 5.1 4.9 4.9 4.8 4.8 4.9

8
50ZPA
Cooling capacities (cont)
See Legend and Notes on page 9.
50ZPA048 High Capacity
Temp (F) Outdoor Air
Entering Condenser
Evaporator Air - CFM/BF
1400/0.07 1600/0.08 1800/0.09
Evaporator Air - Ewb (F)
57 62 63* 67 72 57 62 63* 67 72 57 62 63* 67 72
75
TC 42.4 43.6 44.3 47.7 52.3 44.4 44.8 45.3 48.7 53.4 46.0 46.0 46.1 49.5 54.3
SHC 41.4 39.6 32.0 33.2 26.7 43.3 42.7 34.3 35.7 28.3 44.9 44.9 36.5 38.0 29.8
kW 3.6 3.6 3.6 3.6 3.6 3.7 3.7 3.7 3.7 3.7 3.8 3.8 3.8 3.8 3.8
85
TC 41.2 42.0 42.6 45.9 50.5 43.0 43.2 43.6 46.9 51.5 44.5 44.6 44.4 47.7 52.3
SHC 40.2 38.8 31.3 32.5 26.0 42.0 41.8 33.5 34.9 27.6 43.5 43.5 35.7 37.3 29.1
kW 3.9 3.9 3.9 4.0 4.0 4.0 4.0 4.0 4.0 4.1 4.1 4.1 4.1 4.1 4.2
95
TC 39.8 40.4 40.9 44.1 48.5 41.6 41.6 41.8 45.0 49.4 43.0 43.1 42.5 45.7 50.2
SHC 38.9 38.0 30.5 31.8 25.3 40.6 40.6 32.8 34.2 26.9 42.0 42.1 34.9 36.5 28.3
kW 4.3 4.3 4.3 4.3 4.4 4.4 4.4 4.4 4.4 4.4 4.5 4.5 4.5 4.5 4.5
105
TC 38.4 38.7 39.1 42.2 46.4 40.1 40.1 40.0 43.0 47.3 41.4 41.5 40.6 43.7 48.0
SHC 37.5 37.2 29.7 31.0 24.6 39.1 39.2 32.0 33.4 26.1 40.5 40.5 34.1 35.7 27.6
kW 4.7 4.7 4.7 4.7 4.8 4.8 4.8 4.8 4.8 4.9 4.9 4.9 4.9 4.9 4.9
115
TC 36.9 37.0 37.3 40.2 44.3 38.5 38.5 38.1 41.0 45.1 39.8 39.8 38.7 41.6 45.7
SHC 36.0 36.1 29.0 30.2 23.8 37.6 37.6 31.2 32.6 25.3 38.8 38.9 33.3 34.9 26.8
kW 5.2 5.2 5.2 5.2 5.2 5.2 5.2 5.2 5.3 5.3 5.3 5.3 5.3 5.4 5.4
125
TC 35.3 35.4 35.3 38.1 42.0 36.8 36.8 36.0 38.9 42.8 38.0 38.1 36.6 39.4 43.3
SHC 34.5 34.5 28.1 29.4 23.0 35.9 36.0 30.3 31.8 24.5 37.1 37.2 32.4 34.1 26.0
kW 5.6 5.6 5.6 5.7 5.7 5.7 5.7 5.7 5.7 5.8 5.8 5.8 5.8 5.8 5.9
50ZPA048 Low Capacity
Temp (F) Outdoor Air
Entering Condenser
Evaporator Air - CFM/BF
950/0.06 1100/0.07 1250/0.08
Evaporator Air - Ewb (F)
57 62 63* 67 72 57 62 63* 67 72 57 62 63* 67 72
75
TC 29.4 30.3 30.8 33.1 36.3 30.9 31.1 31.5 33.9 37.1 32.1 32.2 32.2 34.5 37.7
SHC 28.7 27.4 22.2 23.0 18.6 30.2 29.8 23.9 24.9 19.8 31.4 31.4 25.6 26.7 20.9
kW 2.1 2.1 2.1 2.2 2.2 2.2 2.2 2.2 2.2 2.3 2.3 2.3 2.3 2.3 2.4
85
TC 28.6 29.3 29.8 32.0 35.1 30.0 30.2 30.5 32.7 35.8 31.2 31.3 31.0 33.3 36.4
SHC 28.0 26.9 21.7 22.6 18.2 29.3 29.3 23.5 24.4 19.3 30.5 30.5 25.1 26.2 20.5
kW 2.4 2.4 2.4 2.5 2.5 2.5 2.5 2.5 2.5 2.6 2.6 2.6 2.6 2.6 2.7
95
TC 27.8 28.2 28.7 30.8 33.8 29.1 29.2 29.4 31.5 34.5 30.2 30.3 29.9 32.0 35.1
SHC 27.1 26.4 21.3 22.1 17.7 28.4 28.5 23.0 23.9 18.9 29.5 29.6 24.6 25.7 20.0
kW 2.8 2.8 2.8 2.8 2.8 2.8 2.8 2.8 2.9 2.9 2.9 2.9 2.9 3.0 3.0
105
TC 26.9 27.1 27.5 29.6 32.5 28.2 28.2 28.2 30.2 33.1 29.2 29.3 28.7 30.7 33.6
SHC 26.3 25.9 20.8 21.6 17.2 27.5 27.5 22.5 23.4 18.4 28.5 28.6 24.1 25.2 19.5
kW 3.1 3.1 3.1 3.2 3.2 3.2 3.2 3.2 3.2 3.3 3.3 3.3 3.3 3.3 3.3
115
TC 25.9 26.0 26.3 28.3 31.1 27.1 27.2 26.9 28.9 31.7 28.1 28.2 27.4 29.4 32.1
SHC 25.3 25.3 20.3 21.1 16.7 26.5 26.5 22.0 22.9 17.9 27.5 27.5 23.6 24.7 19.0
kW 3.5 3.5 3.5 3.5 3.6 3.6 3.6 3.6 3.6 3.7 3.7 3.7 3.7 3.7 3.7
125
TC 24.9 24.9 25.0 26.9 29.6 26.0 26.1 25.6 27.5 30.1 26.9 27.0 26.0 27.9 30.5
SHC 24.3 24.3 19.7 20.6 16.2 25.4 25.4 21.4 22.4 17.3 26.3 26.3 23.0 24.1 18.5
kW 3.9 3.9 3.9 4.0 4.0 4.0 4.0 4.0 4.0 4.1 4.1 4.1 4.1 4.1 4.2

9
50ZPA
Cooling capacities (cont)
LEGEND
BF — Bypass Factor
Ewb — Entering Wet Bulb
Idb — Leaving Dry Bulb
Iwb — Leaving Wet Bulb
MBtuh — 1000 Btuh (NET)
NOTES:
1. Direct interpolation is permissible. Do not extrapolate.
2. The following formulas may be used:
50ZPA060 High Capacity
Temp (F) Outdoor Air
Entering Condenser
Evaporator Air - CFM/BF
1750/0.07 1875/0.08 2000/0.09
Evaporator Air - Ewb (F)
57 62 63* 67 72 57 62 63* 67 72 57 62 63* 67 72
75
TC 51.5 52.1 52.8 56.7 62.0 52.7 52.8 53.4 57.2 62.6 55.5 55.5 54.8 58.6 64.0
SHC 48.9 48.1 38.5 40.0 31.6 50.0 49.9 39.9 41.5 32.5 52.7 52.7 44.0 46.0 35.4
kW 4.3 4.3 4.3 4.4 4.5 4.4 4.4 4.4 4.5 4.6 4.5 4.5 4.5 4.6 4.7
85
TC 49.7 49.9 50.5 54.1 59.2 50.7 50.8 51.0 54.6 59.7 53.3 53.4 52.2 55.9 60.9
SHC 47.1 46.9 37.5 39.0 30.6 48.1 48.2 38.9 40.5 31.6 50.6 50.7 43.0 44.9 34.4
kW 4.7 4.7 4.7 4.8 4.9 4.8 4.8 4.8 4.9 5.0 5.0 5.0 4.9 5.0 5.1
95
TC 47.8 47.8 48.1 51.5 56.3 48.7 48.8 48.6 52.0 56.8 51.2 51.2 49.7 53.1 57.9
SHC 45.3 45.4 36.5 38.0 29.6 46.2 46.3 37.9 39.5 30.6 48.5 48.6 42.0 43.9 33.4
kW 5.2 5.2 5.2 5.3 5.4 5.3 5.3 5.3 5.4 5.5 5.4 5.4 5.4 5.5 5.6
105
TC 45.8 45.9 45.8 49.0 53.5 46.7 46.8 46.2 49.4 53.9 48.9 49.0 47.2 50.4 54.8
SHC 43.5 43.5 35.5 37.0 28.6 44.3 44.4 36.9 38.5 29.6 46.4 46.5 40.9 42.9 32.4
kW 5.7 5.7 5.7 5.8 5.9 5.8 5.8 5.8 5.9 6.0 5.9 5.9 5.9 6.0 6.1
115
TC 43.8 43.8 43.4 46.3 50.4 44.6 44.7 43.7 46.7 50.6 46.6 46.7 44.7 47.6 51.4
SHC 41.6 41.6 34.6 36.0 27.6 42.3 42.4 35.9 37.5 28.5 44.3 44.3 39.9 41.8 31.3
kW 6.3 6.3 6.3 6.3 6.4 6.4 6.4 6.4 6.4 6.5 6.5 6.5 6.5 6.5 6.6
125
TC 41.6 41.7 40.8 43.6 47.9 42.4 42.4 41.2 44.0 48.1 44.2 44.3 42.0 44.7 48.4
SHC 39.5 39.6 33.5 35.0 26.8 40.2 40.3 34.9 36.5 27.7 42.0 42.0 38.7 40.6 30.3
kW 6.9 6.9 6.9 6.9 7.1 7.0 7.0 7.0 7.0 7.1 7.1 7.1 7.1 7.1 7.2
50ZPA060 Low Capacity
Temp (F) Outdoor Air
Entering Condenser
Evaporator Air - CFM/BF
1150/0.05 1300/0.06 1500/0.07
Evaporator Air - Ewb (F)
57 62 63* 67 72 57 62 63* 67 72 57 62 63* 67 72
75
TC 34.1 35.1 35.8 38.7 42.6 35.7 36.1 36.6 39.5 43.4 37.4 37.5 37.5 40.4 44.2
SHC 33.9 32.3 25.9 27.0 21.6 35.4 34.8 27.7 28.9 22.8 37.1 37.2 30.0 31.4 24.3
kW 2.7 2.6 2.6 2.6 2.6 2.7 2.7 2.7 2.7 2.7 2.7 2.8 2.8 2.8 2.8
85
TC 33.1 33.8 34.4 37.2 41.0 34.5 34.7 35.2 38.0 41.7 36.2 36.2 36.0 38.8 42.5
SHC 32.8 31.7 25.3 26.4 21.0 34.3 34.1 27.1 28.3 22.2 35.9 36.0 29.4 30.8 23.7
kW 3.0 2.9 2.9 2.9 2.9 3.0 3.0 3.0 3.0 3.0 3.0 3.1 3.1 3.1 3.1
95
TC 32.0 32.4 33.0 35.7 39.4 33.4 33.4 33.7 36.4 40.1 34.9 35.0 34.5 37.2 40.7
SHC 31.7 31.0 24.7 25.8 20.4 33.1 33.1 26.5 27.7 21.6 34.6 34.7 28.7 30.1 23.1
kW 3.3 3.2 3.2 3.2 3.2 3.3 3.3 3.3 3.3 3.3 3.3 3.4 3.4 3.4 3.4
105
TC 30.9 31.1 31.6 34.2 37.7 32.2 32.2 32.3 34.8 38.1 33.7 33.7 33.0 35.5 39.1
SHC 30.6 30.4 24.1 25.2 19.8 31.9 32.0 25.8 27.0 20.9 33.4 33.4 28.1 29.5 22.6
kW 3.7 3.6 3.6 3.6 3.6 3.7 3.7 3.7 3.7 3.7 3.7 3.7 3.7 3.8 3.8
115
TC 29.8 29.8 30.2 32.7 36.2 31.0 31.1 30.8 33.3 36.7 32.4 32.4 31.5 33.9 37.1
SHC 29.5 29.6 23.5 24.6 19.3 30.8 30.8 25.2 26.4 20.4 32.1 32.2 27.5 28.8 21.8
kW 4.1 4.0 4.0 4.0 4.0 4.1 4.1 4.1 4.1 4.1 4.1 4.2 4.2 4.2 4.2
125
TC 28.7 28.7 28.9 31.1 35.1 29.9 29.9 29.4 31.8 35.3 31.0 31.4 30.0 32.1 35.1
SHC 28.5 28.5 22.9 24.0 18.9 29.6 29.7 24.6 25.8 19.9 30.7 31.2 26.9 28.1 21.2
kW 4.5 4.5 4.5 4.5 4.5 4.6 4.6 4.5 4.6 4.6 4.6 4.6 4.6 4.6 4.7
sensible capacity (MBtuh x 1000)
t=t
ldb edw 1.10 x cfm
t = Wet-bulb temperature corresponding to enthalpy of air leaving
lwb indoor coil (h )
lwb
total capacity (MBtuh x 1000)
h=h
lwb ewb 4.5 cfm
Where: h = Enthalpy of air entering indoor coil
ewb
3. The sensible heat capacity is based on 80°F edb temperature of air
entering indoor coil.
Below 80°F edb, subtract (corr factor x cfm) from the sensible heat
capacity.
Above 80°F edb, add (corr factor x cfm) to the sensible heat
capacity. Correction Factor = 1.10 x (1–BF) x (edb – 80).

10
50ZPA
WET COIL PRESSURE DROP
FILTER PRESSURE DROP (in. wg)
ACCESSORY ELECTRIC HEAT PRESSURE DROP (in. wg)
UNIT SIZE
STANDARD CFM (S.C.F.M.)
600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000
024
0.027 0.034 0.040 0.047 0.053 — — — — — — — — — —
030 — 0.036 0.042 0.050 0.055 0.063 0.072 0.081 — — — — — — —
036 — — — 0.050 0.055 0.063 0.072 0.081 0.090 0.097 — — — — —
042 — — — — 0.042 0.049 0.052 0.059 0.065 0.071 0.078 0.085 0.091 — —
048 — — — — — — 0.072 0.081 0.090 0.097 0.108 0.120 0.129 0.139 —
060 — — — — — — — — — 0.071 0.078 0.085 0.091 0.098 0.114
UNIT
SIZE
50ZPA
FILTER
SIZE
(in.)
CFM
500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 2300
024-036
24 x 24 0.06 0.07 0.08 0.08 0.09 0.09 0.09 0.10 0.11 0.12 0.14 0.15 ———————
042-060 30 x 30 — — — — — — — — 0.08 0.09 0.10 0.11 0.12 0.13 0.14 0.15 0.16 0.17 0.18
HEATER
kW
CFM
600 800 1000 1200 1400 1600 1800 2000 2200
5-20
0.06 0.08 0.10 0.13 0.15 0.18 0.20 0.23 0.25

11
50ZPA
DRY COIL AIR DELIVERY* — HORIZONTAL DISCHARGE
(Deduct 10% for 208-Volt Operation)
UNIT
50ZPA
SPEED
TAP
AIR
DELIVERY
208 VOLT HORIZONTAL DISCHARGE
External Static Pressure (in.wg)
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
024
1Watts
— 99 100 118 130 142 — — — —
C.F.M. — 848 793 757 698 632 — — — —
2Watts
—————222233244257260
C.F.M. —————970918861795729
030
2Watts
— 155 146 157 170 — — — — —
C.F.M. — 1108 995 951 884 — — — — —
3Watts
—————261275286291315
C.F.M. —————1117 1053 1014 980 877
036
1Watts 180 166 179 191 204 216 — — — —
C.F.M. 1344 1215 1172 1136 1095 1051 — — — —
2Watts — — — 261 276 290 301 316 329 342
C.F.M. — — — 1343 1304 1272 1234 1190 1148 1100
042
3Watts 269 283 305 321 336 349 360 — — —
C.F.M. 1440 1404 1369 1333 1301 1273 1239 — — —
4Watts — — 418 432 450 465 480 490 503 518
C.F.M. — — 1572 1543 1504 1475 1441 1418 1380 1332
048
1Watts — 204 209 216 229 236 249 — — —
C.F.M. — 1129 1087 1027 994 932 881 — — —
2Watts — — 233 245 254 266 276 289 — —
C.F.M. — — 1164 1122 1066 1025 954 906 — —
3Watts 386 398 409 418 425 435 438 441 451 —
C.F.M. 1680 1652 1625 1583 1555 1515 1477 1444 1403 —
4Watts — 440 448 457 462 469 477 480 485 486
C.F.M. — 1745 1717 1684 1651 1612 1573 1537 1508 1470
060
1Watts 224 235 251 266 277 291 298 — — —
C.F.M. 1334 1288 1259 1224 1181 1157 1117 — — —
2Watts — — 286 301 311 325 333 344 370 —
C.F.M. — — 1333 1296 1261 1232 1199 1170 1062 —
3Watts 608 626 643 660 668 685 697 — — —
C.F.M. 1931 1900 1878 1844 1817 1789 1755 — — —
4Watts 737 755 770 787 799 817 826 812 782 —
C.F.M. 2093 2061 2028 2001 1971 1934 1899 1850 1757 —
*Air delivery values are based on operating voltage of 230v or dry coil,
without filter or electric heater. Deduct wet coil, filter, and electric heater
pressure drops to obtain external static pressure available for ducting.
NOTES:
1. Do not operate the unit at a cooling airflow that is less than 350 cfm
for each 12,000 Btuh of rated cooling capacity. Evaporator-coil frost-
ing may occur at airflows below this point.
2. Dashes indicate portions of the table that are beyond the blower mo-
tor capacity or are not recommended.

12
50ZPA
Typical wiring schematic — 208/230-1-60 50ZPA024-042

13
50ZPA
Typical wiring schematic — 208/230-1-60 50ZPA048-060

14
50ZPA
Typical field wiring (cont)
Typical Electric Heater Diagram

15
50ZPA
Electrical data
UNIT
50ZPA
NOMINAL
VOLTAGE
(V-Ph-Hz)
VOLTAGE
RANGE COMPRESSOR OFM IFM ELECTRIC HEAT POWER SUPPLY
Min Max RLA LRA FLA FLA Nominal kW* FLA MCA
MAX FUSE
OR CKT. BKR.
MOCP
024 208/230-1-60 187 253 10.9 54.0 0.9 4.1
–/– –/– 18.6/18.6 25/25 —
3.8/5 18.1/20.8 27.7/31.2 30/35 —
7.5/10 36.1/41.7 50.3/57.2 60/60 —
5.4/7.2 26/30 37.6/42.6 40/45 —
030 208/230-1-60 187 253 13.5 72.5 0.9 4.1
–/– –/– 21.8/21.8 30/30 —
3.8/5 18.1/20.8 27.7/31.2 30/35 —
7.5/10 36.1/41.7 50.3/57.2 60/60 —
11.3/15 54.2/62.5 72.8/83.3 — 80/90
5.4/7.2 26/30 37.6/42.6 40/45 —
036 208/230-1-60 187 253 17.5 88.0 1.5 6.0
–/– –/– 29.4/29.4 35/35 —
3.8/5 18.1/20.8 30.1/33.5 35/35 —
7.5/10 36.1/41.7 52.6/59.6 60/60 —
11.3/15 54.2/62.5 75.2/85.6 — 80/90
5.4/7.2 26/30 40.0/45.0 40/45 —
042 208/230-1-60 187 253 19.4 104.0 1.5 6.0
–/– –/– 31.7/31.7 40/40 —
3.8/5 18.1/20.8 31.7/33.5 40/40 —
7.5/10 36.1/41.7 52.6/59.6 60/60 —
11.3/15 54.2/62.5 75.2/85.6 — 80/90
15/20 72.2/83.3 97.8/111.7 — 100/125
5.4/7.2 26/30 40.0/45.0 40/45 —
048 208/230-1-60 187 253 24.7 116.0 1.5 7.7
–/– –/– 40.0/40.0 50/50 —
3.8/5 18.1/20.8 40.0/40.0 50/50 —
7.5/10 36.1/41.7 54.8/61.7 — 60/70
11.3/15 54.2/62.5 77.3/87.8 — 80/90
15/20 72.2/83.3 99.9/113.8 — 100/125
5.4/7.2 26/30 42.1/47.1 50/50 —
060 208/230-1-60 187 253 28.0 118.0 3.0 7.7
–/– –/– 45.7/45.7 60/60 —
3.8/5 18.1/20.8 45.7/45.7 60/60 —
7.5/10 36.1/41.7 54.8/61.7 60/60 —
11.3/15 54.2/62.5 77.3/87.8 — 80/90
15/20 72.2/83.3 99.9/113.8 — 100/125
5.4/7.2 26/30 42.1/47.1 60/60 —
LEGEND
FLA — Full Load Amps
LRA — Locked Rotor Amps
MCA — Minimum Circuit Amps
MOCP — Maximum Overcurrent Protection
RLA —Rated Load Amps
NOTES:
1. In compliance with NEC (National Electrical Code) requirements
for multimotor and combination loadequipment (refer to NEC
Articles430and 440), the overcurrent protective device for the
unit shall be Power Supply fuse . The CGA (CanadianGas
Association) unitsmaybefuse or circuit breaker.
2. Minimum wire size is based on 60 C copper wire. If other than
60 C wire isused, or if length exceedswire length in table,
determine size from NEC.
®
*Heater capacity (KW) based on heater voltage of 208v, 240v, & 480v.
If power distribution voltage to unit variesfrom rated heater voltage,
heater KW will vary accordingly.

16
50ZPA
Typical Installation
C00008
TOP COVER
INDOOR
THERMOSTAT
DISCONNECT
PER NEC*
(UNIT AND
ELECTRIC
HEATER)
FROM
POWER
SOURCE
RETURN
AIR
POWER AND
LOW-VOLTAGE
ENTRY
COMPOSITE
RUST-PROOF
BASEPAN
CONDENSATE
DRAIN
CONNECTION
*Separate disconnect per NEC
(National Electrical Code) required
for electric heater when single-
point conection is not used.
Power Wiring
Control Wiring
Condenser Airflow
Evaporator Airflow
Cooling Operation (024 - 042)
With a call for cooling (Y/Y2), the indoor fan energizes imme-
diately where as the contactor energizes after a 5 minute time
delay (in case of an initial start up) starting the compressor and
the outdoor fan motor. When the cooling demand is met, Y/Y2
de-energizes, shutting the compressor, indoor fan and the out-
door fan.
Cooling Operation (048 and 060)
These units utilize a 2 stage indoor thermostat. With a first stage
call for cooling (Y1), the indoor fan (low stage) energizes im-
mediately where as the contactor energizes after a 5 minute time
delay (in case of an initial start up) starting the compressor (low
stage) and the outdoor fan motor. If the low stage operation can-
not satisfy the cooling demand, the second stage cooling (Y2)
energizes switching the compressor into high stage cooling
through energizing an internal solenoid valve inside the scroll
compressor and switching the indoor fan into high stage. When
second stage cooling is satisfied, Y2 de-energizes switching the
compressor and the indoor fan into low stage cooling. When the
low stage cooling demand is met, Y1 de-energizes shutting the
compressor, indoor fan and the outdoor fan.
Heating Operation (024 - 042)
With a call for heating (W2), the auxiliary or electric heat ener-
gizes along with the indoor blower. In case of staged heating,
W3 is energized if the demand is not met. The highest airflow
selected is run while the electric heat is in operation. When heat-
ing demand is met, W3 and W2 sequentially de-energize shut-
ting the indoor fan and the electric heater.
Heating Operation (048 and 060)
With a call for heating (W2), the auxiliary electric heater is en-
ergized along with the indoor blower. If the demand is not met,
W3 is energized in case of staged heating. When heating de-
mand is satisfied, W3 and W2 sequentially de-energize along
with the indoor fan blower.
Continuous Fan:
With the continuous indoor fan option selected on the thermo-
stat, G is continuously energized. In case of 024 - 042 units, the
selected airflow setting is provided. In case of 048 and 060
units, the system runs low stage (Y1) airflow for continuous fan
operation.
Operating sequence

17
50ZPA
APPLICATION DATA
ACCESSORY ELECTRIC HEATERS
LEGEND
ODS — Order Distribution System
NOTE: Electric heaters are rated at 240 v and 480 v. Refer to Multiplication Factors table below for voltages in other applications.
MULTIPLICATION FACTORS
Example: 15.0 kW (at 240v) heater on 208 v
= 15.0 (.75 mult factor)
= 11.25 capacity at 208 v
ODS CATALOG
ORDERING NO.
NOMINAL
CAPACITY (kW)
USED WITH SIZES
024 030 036 042 048 060
ELECTRIC HEATERS (208/240-1-60)
CPHEATER096A00 x 5kWxxxxx
CPHEATER097A00 5kWxxxxx
CPHEATER098A00 x 7.5 kW xxxxx
CPHEATER099A00 7.5 kW xxxxx
CPHEATER100A00 x10kWxxxxx
CPHEATER101A00 10kWxxxxx
CPHEATER102A00 x15kW xxxx
CPHEATER103A00 x 20 kW x x x
HEATER kW
RATING
VOLTAGE DISTRIBUTION
V/3/60 MULTIPLICATION FACTOR
240
200
208
230
240
.69
.75
.92
1.00

18
50ZPA
GENERAL: Furnish and install outdoor package, electrically
controlled, air conditioner utilizing a reciprocating compressor
for cooling duty. Unit shall discharge supply air horizontally or
vertically as shown on contract drawings.
Nominal unit electrical characteristics shall be ______ v,
______ ph, 60 Hz. The unit shall be capable of satisfactory
operation within voltage limits of ______ v to ______ v. Unit
power wiring shall enter unit cabinet at a single location.
Separate power supply shall not be required for electric heat.
COOLING CAPACITY: Total cooling capacity of the unit
shall be _____ Btuh or greater, and sensible capacity shall be
______ Btuh or greater at conditions of ______ cfm indoor air
entering unit at ______F dry bulb, _____ F wet bulb and
outdoor entering air of ______F dry bulb. Total design
conditions shall be a minimum of ______ Btuh/Watt. The unit
shall be capable of cooling operation down to 40 F as shipped
from the factory.
CABINET: Unit cabinet shall be constructed of phosphated,
bonderized, zinc-coated, prepainted steel. Basepan shall be
made of a single-piece non-corrosive, composite material.
Evaporator-fan compartment interior cabinet surfaces shall be
insulated with a minimum 1/2-in. thick, flexible fiberglass
insulation, coated on the air side with aluminum foil.
Cabinet panels shall be easily removable for servicing.
Outdoor coil shall be protected by metal louvered panels.
COMPRESSOR: Compressor shall be fully hermetic type
with internal and external vibration isolation.
CONDENSER SECTION: Condenser fan shall be of the
direct-driven propeller type with aluminum blades, riveted to
corrosion-resistant steel spiders, and shall be dynamically
balanced and discharge air horizontally or vertically upwards.
Condenser coils shall have aluminum-plate fins mechanically
bonded to seamless copper tubes with all joints brazed.
Tube sheet openings shall be belled to prevent tube wear.
EVAPORATOR SECTION: Fan shall be 2- or 3-speed with
direct drive motor as shown on the equipment drawings.
Fan wheel shall be made from steel, be double-inlet type with
forward-curved blades with a corrosion-resistant finish and
dynamically balanced.
Evaporator coils shall have aluminum-plate fins mechanically
bonded to seamless copper tubes with all joints brazed.
Tube sheet openings shall be belled to prevent tube wear.
MOTORS: Compressor motors shall be of the refrigerant-
cooled type with line break thermal and current overload
protection.
All fan motors shall have permanently lubricated bearings, and
inherent automatic reset thermal overload protection.
Condenser fan motor shall be open drip-proof.
REFRIGERANT SYSTEM: Refrigerant system shall include
fixed orifice metering system.
CONTROLS: Unit shall be complete with self-contained low-
voltage control circuit.
APPROVALS: Unit shall be UL listed as a total package for
safety requirements. All wiring shall be in accordance with
NEC.
Unit shall be rated in accordance with ARI Standards 210/240-
89 and 270-84.
Cabinet insulation shall conform to ASHRAE No. 62P.
Insulation and adhesive shall meet NFPA 90A requirements for
flame spread and smoke generation.
Unit shall have a sloped drain pan that conforms to ASHRAE
Standard 62-89.
ACCESSORIES: Field-installed accessories shall include
solid-state compressor short-cycle device, outdoor thermostat,
thermostat and subbase, electric heaters with single-point
connection, crankcase heater (230-1-60), low- and high-
pressure switch kits, and low-ambient kit.
Engineers’ specification guide

19
50ZPA

Copyright 2005 Carrier Corp. • 7310 W. Morris St. • Indianapolis, IN 46231 Printed in U.S.A. edition date: 10/05
Manufacturer reserves the right to change, at any time, specifications or designs without notice and obligations Catalog No: 50ZPA-1PD Replaces: New