Carrier CAS072 Dimensions and installation guide

CAS-072-153-01SI Rev. A 1-23
Installation, Start-Up and Service Instructions
CONTENTS
Page
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . 1
INSTALLATION GUIDELINES . . . . . . . . . . . . . . 2
Replacement/Retrofit — R-22 to R-410A
Refrigerant . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Rated Indoor Airflow (cfm) . . . . . . . . . . . . . . . . . 2
Matching CAS Model to Evaporator Coil . . . . . 3
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Jobsite Survey . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Step 1 — Plan for Unit Location . . . . . . . . . . . . 6
Step 2 — Complete Pre-Installation Checks . . 7
Step 3 — Prepare Unit Mounting Support . . . . 7
Rig and Mount the Unit . . . . . . . . . . . . . . . . . . . 7
Step 4 — Determine Refrigerant Line Sizes . . . 7
Suction Riser . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Step 5 — Complete Refrigerant Piping
Connections . . . . . . . . . . . . . . . . . . . . . . . . . 10
Step 6 — Install Accessories . . . . . . . . . . . . . . 13
Step 7 — Complete Electrical Connections . . 13
Step 8 — Wind Baffles for Low Ambient
Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
PRE-START-UP . . . . . . . . . . . . . . . . . . . . . . . . . 18
System Check . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Turn On Crankcase Heater . . . . . . . . . . . . . . . 18
Preliminary Charge . . . . . . . . . . . . . . . . . . . . . . 18
START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Preliminary Checks . . . . . . . . . . . . . . . . . . . . . 18
Start Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
OPERATING SEQUENCE . . . . . . . . . . . . . . . . . 25
Base Unit Controls . . . . . . . . . . . . . . . . . . . . . . 25
All Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . 26
Quarterly Inspection
(and 30 days after initial start) . . . . . . . . . . . 26
Seasonal Maintenance . . . . . . . . . . . . . . . . . . . 26
SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Refrigeration System . . . . . . . . . . . . . . . . . . . . 27
Comfort Alert Diagnostic Module . . . . . . . . . . 28
Compressor Protection . . . . . . . . . . . . . . . . . . 31
Routine Cleaning of Round-Tube Plate Fin
(RTPF) Coils . . . . . . . . . . . . . . . . . . . . . . . . . 31
Fastener Torque Values . . . . . . . . . . . . . . . . . . 32
TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . 32
APPENDIX A — AIR CONDITIONER AND HEAT
PUMP WITH R-410A –
QUICK REFERENCE GUIDE . . . . . . . . . . . . . 35
APPENDIX B — WIRING DIAGRAMS . . . . . . . 35
APPENDIX C — LOW AMBIENT OPTION . . . . 50
START-UP CHECKLIST . . . . . . . . . . . . . . . . . CL-1
SAFETY CONSIDERATIONS
Improper installation, adjustment, alteration, service,
maintenance, or use can cause explosion, fire, electrical
shock or other conditions which may cause personal injury
or property damage. Consult a qualified installer, service
agency, or your distributor or branch for information or
assistance. The qualified installer or agency must use
factory-authorized kits or accessories when modifying this
product. Refer to the individual instructions packaged with
the kits or accessories when installing.
Follow all safety codes. Wear safety glasses and work
gloves. Use quenching cloths for brazing operations and
have a fire extinguisher available. Read these instructions
thoroughly and follow all warnings or cautions attached to
the unit. Consult local building codes and appropriate
national electrical codes (in U.S.A., ANSI/NFPA70, National
Electrical Code (NEC); in Canada, CSA C22.1) for special
requirements.
It is important to recognize safety information. This is the
safety-alert symbol . When you see this symbol on the
unit and in instructions or manuals, be alert to the potential
for personal injury.
Understand the signal words DANGER, WARNING,
CAUTION, and NOTE. These words are used with the
safety-alert symbol. DANGER identifies the most serious
hazards which will result in severe personal injury or death.
WARNING signifies hazards which could result in personal
injury or death. CAUTION is used to identify unsafe
practices, which may result in minor personal injury or
product and property damage. NOTE is used to highlight
suggestions which will result in enhanced installation,
reliability, or operation.
DANGER
ELECTRICAL SHOCK HAZARD
Failure to follow this warning will result in personal injury
or death.
Before performing service or maintenance operations
on unit, turn off main power switch to unit and install
lock(s) and lockout tag(s). Ensure electrical service to
rooftop unit agrees with voltage and amperage listed on
the unit rating plate. Do not check compressor ohms at
compressor terminals. Unit may have more than one
power switch.
WARNING
UNIT OPERATION AND SAFETY HAZARD
Failure to follow this warning could cause personal
injury, death and/or equipment damage.
R-410A refrigerant systems operate at higher pressures
than standard R-22 systems. Do not use R-22 service
equipment or components on R-410A refrigerant
equipment.
CAS072-153
Air-Cooled Condensing Units
with R-410A Refrigerant

2Specifications subject to change without notice. CAS-072-153-01SI Rev. A
INSTALLATION GUIDELINES
Replacement/Retrofit — R-22 to R-410A
Refrigerant
Replacement/retrofit installations require change-out of out-
door unit, metering device, and filter driers. Change-out of
indoor coil (evaporator) and interconnecting tubing is
recommended.
EXISTING EVAPORATOR COIL
If the existing evaporator coil is intended to be re-used,
check with the coil manufacturer to verify the coil construc-
tion is suitable for operation with the higher pressures of
R-410A refrigerant. Also determine if the existing TXV valve
is compatible with R-410A; replace if necessary. The mini-
mum factory test pressure rating must be 250 psig
(1725 kPa). Existing coil will need to be purged with Nitro-
gen to remove as much mineral oil as possible to eliminate
cross contamination of oils.
ACID TEST
If the existing system is being replaced because of a com-
pressor electrical failure, assume acid is in system. If sys-
tem is being replaced for any other reason, use an ap-
proved acid test kit to determine acid level. If even low lev-
els of acid are detected, install a 100 percent activated
alumina suction-line filter drier in addition to the replacement
liquid-line filter drier. Remove the suction line filter drier as
soon as possible, with a maximum of 72 hr of operation.
Recommendation: Install a ball valve in the liquid line at the
filter drier location when installing a suction filter in the suc-
tion line.
EXISTING REFRIGERATION PIPING
Reuse of existing refrigerant piping involves three issues:
quality (strength) of existing tubing, cleanliness and tube
size. Inspect all tube segments and joints for signs of dam-
age, corrosion or poor brazing. Flush the interconnecting
piping system with dry Nitrogen to eliminate as much trace
of mineral oil as possible.
Same tube sizes are capable of handling higher flow rates
(expressed as tons of cooling capacity) with R-410A refrig-
erant compared to R-22 at constant pressure drops. For ex-
ample, a 1/2-inch OD liquid line is rated at 33% higher tons
with R-410A than with R-22 (at 5°F pressure drop). A
1-1/8 inch OD suction line is rated at 53% higher tons with
R-410A than with R-22 (at 2°F pressure drop). Refrigeration
lines selected for R-22 use are typically oversized for
R-410A applications. Carefully check the existing suction
line size against the table for maximum size; replace vertical
riser segments if necessary. Check existing liquid line size
against sizing data in Tables 8 and 9 or; replace with smaller
lines when feasible.
INSTALLATION
1. Remove the existing evaporator coil or fan coil and
install the replacement coil when appropriate.
2. Drain oil from low points and traps in suction line tub-
ing and evaporator if they were not replaced. Remov-
ing oil from evaporator coil may require purging of
the tubing with dry nitrogen.
3. Unless indoor unit is equipped with a R-410A
approved metering device, change the metering
device to a thermal expansion valve (TXV) designed
for R-410A refrigerant.
4. Remove the existing outdoor unit. Install the new out-
door unit according to these installation instructions.
5. Install a new field-supplied liquid-line filter drier at the
indoor coil just upstream of the TXV or fix orifice
metering device.
6. If a suction line filter drier is also to be installed,
install suction line drier downstream of suction line
service valve at condensing unit.
7. If required, install a 100% activated alumina suction
line filter drier at the outdoor unit.
8. Evacuate and charge the system according to the
instructions in this installation manual.
9. Operate the system for 10 hr. Monitor the pressure
drop across the suction line filter drier. If pressure
drop exceeds 3 psig (21kPa), replace suction-line
and liquid-line filter driers. Be sure to purge system
with dry nitrogen and evacuate when replacing filter
driers. Continue to monitor the pressure drop across
suction-line filter drier. Repeat filter changes if neces-
sary. Never leave suction-line filter drier in system
longer than 72 hr (actual time).
GENERAL
See Fig. 1 for CAS model number nomenclature. For unit
dimensions see Fig. 2. For corner weights see Table 4. For
physical data see Tables 5 and 6.
Rated Indoor Airflow (cfm)
Tables 1 and 2 list the rated indoor airflow used for the AHRI
efficiency rating for the units covered in this document.
WARNING
PERSONAL INJURY AND ENVIRONMENTAL
HAZARD
Failure to follow this warning could cause personal injury
or death.
Relieve pressure and recover all refrigerant before
system repair or final unit disposal.
Wear safety glasses and gloves when handling
refrigerants. Keep torches and other ignition sources
away from refrigerants and oils.
CAUTION
PERSONAL INJURY HAZARD
Failure to follow this caution may result in
personal injury.
Sheet metal parts may have sharp edges or burrs. Use
care and wear appropriate protective clothing, safety
glasses and gloves when handling parts and servicing
air conditioning equipment.
CAUTION
EQUIPMENT DAMAGE
Failure to follow this caution can result in equipment
damage.
Do not install a suction-line filter drier in liquid line. A
liquid-line filter drier designed for use with R-410A
refrigerant is required on every unit.
Table 1 — CAS (Single Circuit) with F*S/H or F*X
MODEL NUMBERS FULL LOAD AIRFLOW (CFM)
CAS072 — F*X072 2400
CAS091 — F*X091 3000
CAS121 — F*X120 4000
CAS151 — F*S/H150 4400

CAS-072-153-01SI Rev. A Specifications subject to change without notice. 3
The Model CAS123/153 is a dual-circuit unit design that re-
quires two sets of refrigeration piping between the outdoor
unit and the evaporator coil (or coils). This model can only
be connected to an evaporator coil that has two refrigeration
circuits (or to two separate evaporator coils). The Model
CAS123/153 CANNOT be connected to a single-circuit
evaporator coil. The Model CAS123/153 CANNOT be field-
converted to a single-circuit design. See Table 3.
Before unpacking this new CAS model, compare the evapo-
rator coil design to the CAS model.
Matching CAS Model to Evaporator Coil
The CAS072/091/121/151 units have a single-circuit de-
sign, requiring one set of refrigeration piping. This model
can be connected to an evaporator coil with one circuit or
with two circuits (by manifolding the evaporator connections
into a single piping system).
Fig. 1 — Model Number Nomenclature
Table 2 — CAS (Dual Circuit) with F*S/H or F*X
MODEL NUMBERS FULL LOAD AIRFLOW (CFM)
CAS123 — F*X120 4000
CAS153 — F*S/H150 4400
Table 3 — Evaporator Coil Connections
EVAPORATOR COIL
HAS
CONNECT TO
MODEL NOTES
Single Circuit 072/091/121/151
ONLY —
Two Circuits
072/091/121/151
Manifold evaporator
circuits into single piping
system.
123/153 Use two separate piping
systems
MODEL SERIES C A S 0 9 0 H G A 0 A 0 0 A
Position Number 12345678910111213
14
Type
Voltage
Refrigerant Options
Coil Options
A = None
C = Non-Fused Disconnect
0 = Electro-Mechanical Controls (standard)
0 = Not Used
Base Unit Controls
A = Al/Cu
B = Precoat Al/Cu
C = E−Coat Al/Cu
E = Cu/Cu
M = Al/Cu with Louvered Hail Guards
N = Precoat Al/Cu with Louvered Hail Guards
P = E−Coat Al/Cu with Louvered Hail Guards
R = Cu/Cu with Louvered Hail Guards
Not Used
A = Standard
B = LTL (includes full corrugated sleeve wrapped around unit perimeter and full corrugated top cover) Packaging
Efficiency
072 = 6 Tons (2 stages)
091 = 7.5 Tons (2 stages)
121 = 10 Tons (2 stages)
123 = 10 Tons (3 stages)
151 = 12.5 Tons (2 stages)
153 = 12.5 Tons (3 stages)
H = 208/230-3-60
L = 460-3-60
S = 575-3-60
0 = None
1 = Un-powered Convenience Outlet
G = Single Circuit / Dual Stage (072/091 only)
H = Single Circuit / Dual Stage with Low Ambient Controller (072/091 only)
M = Single Circuit / Dual Stage (121/151 only)1
N = Single Circuit with Low Ambient Controller (121/151 only)1
T = Dual Circuit (123/153 only)
U = Dual Circuit with Low Ambient Controller (123/153 only)
C = R-410A Condensing Unit
A = Air Conditioning (Cooling Only)
S= Standard Efficiency
Nominal Cooling Capacity
Service Options
Electrical Options
1CAS121/151 models with M/N in the 8th digit meet Department of Energy (DOE) 2023 IEER requirements.

4Specifications subject to change without notice. CAS-072-153-01SI Rev. A
Fig. 2 — CAS072-153 Base Unit Dimensions

CAS-072-153-01SI Rev. A Specifications subject to change without notice. 5
Table 4 — CAS Corner Weights
UNIT STD. UNIT WT. CORNER A CORNER B CORNER C CORNER D CENTER OF GRAVITYa
NOTE(S):
a Dimensions are in inches [mm].
UNIT HEIGHTa
lb kg lb kg lb kg lb kg lb kg X Y Z H
CAS072 389 176 141 64 96 44 62 28 91 41 18 [457.2] 24 [609.6] 21 [533.4] 42 3/8 [1076.0]
CAS091 430 195 142 64 96 44 76 34 111 50 18 [457.2] 24 [609.6] 21 [533.4] 42 3/8 [1076.0]
CAS121 490 222 177 80 120 54 78 35 114 52 18 [457.2] 24 [609.6] 24 [609.6] 50 3/8 [1279.2]
CAS151 598 271 195 88 142 64 110 50 151 68 20 [508.0] 25 [635.0] 24 [609.6] 50 3/8 [1279.2]
CAS123 516 234 185 84 117 53 83 38 131 59 19 [482.6] 23 [584.2] 24 [609.6] 50 3/8 [1279.2]
CAS153 654 297 214 97 155 70 120 54 165 75 20 [508.0] 25 [635.0] 24 [609.6] 50 3/8 [1279.2]
Table 5 — CAS072/091/121/151 Single Circuit Models — Physical Data
UNIT CAS072 CAS091 CAS121 CAS151
NOMINAL CAPACITY (tons) 6 7.5 10 12.5
OPERATING WEIGHT (lb) 389 430 490 598
Refrigeration System
No. Circuits / No. Comp. / Type 1 / 1 / Scroll 1 / 1 / Scroll 1 / 1 / Scroll 1 / 1 / Scroll
Refrigerant Type R-410A R-410A R-410A R-410A
R-410A Shipping Charge A/B (lb) 9.09.09.09.0
System Charge w/ Fan Coila14.0 17.0 20.0 43.0
Metering Device TXV TXV TXV TXV
High-Press. Trip / Reset (psig) 630 / 505 630 / 505 630 / 505 630 / 505
Low-Press. Trip / Reset (psig) 54 / 117 54 / 117 54 / 117 54 / 117
Compressor
Oil Charge A/B (oz) 56 60 85 84
Speed (rpm, 60 Hz) 3500 3500 3500 3500
Condenser Coil
Material Al/Cu Al/Cu Al/Cu Al/Cu
Coil Type RTPF RTPF RTPF RTPF
Rows / FPI 2 / 17 2 / 17 2 / 17 3 / 17
Total Face Area (ft2)17.5 17.5 25.1 31.8
Condenser Fan / Motor
Qty / Motor Drive Type 2 / direct 2 / direct 2 / direct 2 / direct
Motor HP / RPM 1/4 / 1100 1/4 / 1100 1/4 / 1100 1/4 / 1100
Fan Diameter (in.) 22 22 22 22
Nominal Airflow (cfm) 6,000 6,000 6,000 6,000
Watts (total) 610 610 610 610
Piping Connections
Qty / Suction (in. ODS) 1 / 1 1/8 1 / 11/8 1 / 13/8 1 / 13/8
Qty / Liquid (in. ODS) 1 / 3/8 1 / 1/2 1 / 1/2 1 / 5/8
NOTE(S):
a Approximate system charge with about 25 ft piping of sizes indicated with matched F*S/H or F*X.

6Specifications subject to change without notice. CAS-072-153-01SI Rev. A
INSTALLATION
Jobsite Survey
Complete the following checks before installation.
1. Consult local building codes and the NEC (National Elec-
trical Code) ANSI/NFPA 70 for special installation
requirements.
2. Determine unit location (from project plans) or select
unit location.
3. Check for possible overhead obstructions which may
interfere with unit lifting or rigging.
Step 1 — Plan for Unit Location
The CAS units are designed and approved for outdoor in-
stallation only. Do not locate these units indoors. Do not add
ducting to unit fan system.
Select a location for the unit and its support system (pad,
rails or other) that provides for the minimum clearances re-
quired for safety. This includes the clearance to combustible
surfaces, unit performance and service access below,
around and above unit as specified in unit drawings. See
Fig. 3.
NOTE: Local codes may require different clearances than
specified in Fig. 3. It is the responsibility of installers to be
knowledgeable in local codes and to modify the recom-
mended clearances to satisfy local codes.
NOTE: Consider also the effect of adjacent units on airflow
performance and control box safety clearance.
Do not install the outdoor unit in an area where fresh air
supply to the outdoor coil may be restricted or when recircu-
lation from the condenser fan discharge is possible. Do not
locate the unit in a well or next to high walls.
Fig. 3 — Service Clearance Dimensional Drawing
Evaluate the path and required line length for interconnect-
ing refrigeration piping, including suction riser requirements
(outdoor unit above indoor unit) and liquid line lift (outdoor
unit below indoor unit). Relocate sections to minimize the
length of interconnecting tubing.
Although unit is weatherproof, avoid locations that permit
water from higher level runoff and overhangs to fall onto the
unit.
Table 6 — CAS123/153 Two Circuit Models – Physical Data
UNIT CAS123 CAS153
NOMINAL CAPACITY (tons) 10 12.5
OPERATING WEIGHT (lb) 516 654
Refrigeration System
# Circuits / # Comp. / Type 2 / 2 / Scroll 2 / 2 / Scroll
Refrigerant Type R-410A R-410A
R-410A Shipping Charge A/B (lb) 9.0 / 9.0 9.0 / 9.0
System Charge w/ Fan Coila
NOTE(S):
a Approximate system charge with about 25 ft piping of sizes indicated with matched F*S/H or F*X.
11.9 / 13.1 16.2 / 16.1
Metering Device TXV TXV
High-Press. Trip / Reset (psig) 630 / 505 630 / 505
Low-Press. Trip / Reset (psig) 54 / 117 54 / 117
Compressor
Oil Charge A/B (oz) 42 / 42 56 / 56
Speed (rpm, 60 Hz) 3500 3500
Condenser Coil
Material Al/Cu Al/Cu
Coil Type RTPF RTPF
Rows / FPI 2 / 17 3 / 17
Total Face Area (ft2)31.8 31.8
Condenser Fan / Motor
Qty / Motor Drive Type 2 / direct 2 / direct
Motor HP / RPM 1/4 / 1100 1/4 / 1100
Fan Diameter (in.) 22 22
Nominal Airflow (cfm) 6,000 6,000
Watts (total) 610 610
Piping Connections
Qty / Suction (in. ODS) 2 / 1 1/8 2 / 1 3/8
Qty / Liquid (in. ODS) 2 / 3/8 2 / 1/2
IMPORTANT: DO NOT BURY REFRIGERANT LINES.
REAR:
Min 18" (457 mm)
required for service
RIGHT:
Min 18" (457 mm)
required for service
LEFT:
Min 18" (457 mm)
required for service
FRONT:
42” (1067 mm)
required for service
NOTE: Observe requirements for 39" (914 mm) operating
clearance on either Left or Rear coil opening.

CAS-072-153-01SI Rev. A Specifications subject to change without notice. 7
Step 2 — Complete Pre-Installation Checks
CHECK UNIT ELECTRICAL CHARACTERISTICS
Confirm before installation of unit that voltage, amperage
and circuit protection requirements listed on unit data plate
agree with power supply provided.
UN-CRATE UNIT
Remove unit packaging except for the top skid assembly,
which should be left in place until after the unit is rigged into
its final location.
INSPECT SHIPMENT
File a claim with shipping company if the shipment is dam-
aged or incomplete.
CONSIDER SYSTEM REQUIREMENTS
Consult local building codes and National Electrical Code
(NEC, U.S.A.) for special installation requirements.
Allow sufficient space for airflow clearance, wiring, refriger-
ant piping, and servicing unit. See Fig. 2 for unit dimensions
and Table 4 for weight distribution data.
Locate the unit so that the outdoor coil (condenser) airflow is
unrestricted on all sides and above.
The unit may be mounted on a level pad directly on the
base channels or mounted on raised pads at support
points. See Table 4 for weight distribution based on rec-
ommended support points.
NOTE: If vibration isolators are required for a particular
installation, use the data in Table 4 to make the proper
selection.
Step 3 — Prepare Unit Mounting Support
SLAB MOUNT
Provide a level concrete slab that extends a minimum of
6 in. (150 mm) beyond unit cabinet. Install a gravel apron in
front of condenser coil air inlet to prevent grass and foliage
from obstructing airflow.
Rig and Mount the Unit
RIGGING
These units are designed for overhead rigging. Refer to the
rigging label for preferred rigging method. Spreader bars are
not required if top crating is left on the unit. All panels must
be in place when rigging. As further protection for coil faces,
plywood sheets may be placed against the sides of the unit,
behind cables. Run cables to a central suspension point so
that the angle from the horizontal is not less than
45 degrees. Raise and set the unit down carefully.
If it is necessary to roll the unit into position, mount the unit
on longitudinal rails, using a minimum of 3 rollers. Apply
force to the rails, not the unit. If the unit is to be skidded into
position, place it on a large pad and drag it by the pad. Do
not apply any force to the unit.
Raise from above to lift the unit from the rails or pad when
unit is in its final position.
After the unit is in position, remove all shipping materials
and top crating.
Step 4 — Determine Refrigerant Line Sizes
Select the recommended line sizes for
CAS072/091/121/151 and CAS123/153 unit from the ap-
propriate tables.
Determine the linear length of interconnecting piping re-
quired between the outdoor unit and indoor unit (evapora-
tor). Consider and identify also the arrangement of the tub-
ing path (quantity and type of elbows in both lines), liquid
line solenoid size, filter drier and any other refrigeration spe-
cialties located in the liquid line. Refer to the indoor unit in-
stallation instructions for additional details on refrigeration
specialties devices.
Determine equivalent line length adjustments for path and
components and add to linear line lengths. See Table 7,
Equivalent Lengths for Common Fittings, for usual fitting
types. Also identify adjustments for refrigeration specialties.
NOTE: Equivalent line lengths will vary based on tube diam-
eter. Calculate equivalent line length for each pipe by add-
ing equivalent length adjustments to linear lengths for each
pipe.
Enter the appropriate table to select the recommended line
sizes.
CAUTION
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage.
All panels must be in place when rigging. Unit is not
designed for handling by fork truck when packaging
is removed.
If using top crate as spreader bar, once unit is set,
carefully lower wooden crate off building roof top to
ground. Ensure that no people or obstructions are below
prior to lowering the crate.
Table 7 — Equivalent Lengths for
Common Fittings (ft)
NOMINAL
TUBE OD
(in.)
ELBOWS
90° Std 90° Lrad 90° Street 90° Std 90° Street
3/8 1.3 0.8 2.2 0.6 1.0
1/2 1.4 0.9 2.3 0.7 1.1
5/8 1.6 1.0 2.5 0.8 1.3
3/4 1.8 1.2 2.9 0.9 1.5
7/8 2.0 1.4 3.2 0.9 1.6
1-1/8 2.6 1.7 4.1 1.3 2.1
1-3/8 3.3 2.3 5.6 1.7 3.0
1-5/8 4.0 2.6 6.3 2.1 3.4
NOMINAL
TUBE OD
(in.)
TEES
Branch
Flow
Straight-Thru
No Reduct Reduce
25%
Reduce
50%
3/8 2.60.81.11.3
1/2 2.70.91.21.4
5/8 3.01.01.41.6
3/4 3.51.21.71.8
7/8 4.01.41.92.0
1-1/8 5.01.72.32.6
1-3/8 7.02.33.13.3
1-5/8 8.02.63.74.0
2-1/8 10.0 3.3 4.7 5.0
UNIT TABLE QUANTITY OF
LINE SETS
CAS072/091/121/151 81
CAS123/153 92

8Specifications subject to change without notice. CAS-072-153-01SI Rev. A
LIQUID LIFT
A liquid lift condition exists when the outdoor unit is located
below the indoor (evaporator) unit and liquid flows vertically
up in a portion of the liquid line. The vertical column of liquid
reduces the available state point sub-cooling at the evapo-
rator coil’s thermal expansion valve. This effect reduces the
length of liquid lift (feet of elevation) that a liquid line size can
accommodate. Longer linear tube lengths will also reduce
the amount of liquid lift possible.
Check Tables 8 (CAS072/091/121/151) and
9 (CAS123/153) for maximum liquid lift capabilities for
line sizes. Reselect the liquid line tube size if necessary.
If maximum available tube size cannot provide the re-
quired lift distance on this installation, relocate the out-
door unit to reduce the equivalent line length or the lift
requirement.
Table 8 — CAS072/091/121/151 Piping Recommendations (Single-Circuit)a
MODEL &
NOMINAL
CAPACITY
LINEAR LINE (FT) 0 - 24 25 - 49 50 - 74 75 - 99 100 - 124 125 - 149 150 - 174 175 - 200
EQUIV. LINE (FT) 0 - 37 38 - 74 75 - 112 113 - 149 150 - 187 188 - 224 225 - 262 263 - 300
CAS 072
TC 68.5,
SC 5.57°F
Liquid Line Size (in.) 3/8 3/8 1/2 1/2 5/8 1/2 5/8 1/2 5/8 1/2 5/8 1/2 5/8 1/2 5/8
Liquid PD (°F) 2.0 4.0 0.7 1.1 0.3 1.4 0.4 1.8 0.5 2.1 0.6 2.5 0.7 2.8 0.8
Max Lift (ft) 18734313944574157355431532752
Max Lift PD (F) 3.5 4.6 3.5 3.5 3.5 5.0 5.0 5.0 5.0 4.9 5.0 5.0 5.0 5.0 5.0
Suction Line Size (in.) 7/8 7/8 1-1/8 7/8 1-1/8 7/8 1-1/8 7/8 1-1/8 1-1/8 1-1/8 1-1/8
Suction Ln PD (F) 0.9 1.8 0.5 2.7 0.8 3.6 1.0 4.5 1.3 1.6 1.8 2.1
Charge (lb) 10.8 11.8 13.7 15.2 18.5 16.9 21.3 18.7 24.2 21.4 27.1 23.4 30.0 25.3 32.8
#/TR 1.90 2.07 2.41 2.67 3.25 2.97 3.74 3.28 4.25 3.8 4.75 4.1 5.26 4.4 5.75
C A S 0 9 1
TC 92.0,
SC 11.3°F
Liquid Line Size (in.) 1/2 1/2 5/8 1/2 5/8 1/2 5/8 1/2 5/8 1/2 5/8 1/2 5/8 1/2 5/8
Liquid PD (°F) 0.6 1.3 0.3 1.9 0.5 2.5 0.7 3.2 0.9 3.8 1.0 4.4 1.2 5.1 1.4
Max Lift (ft) 25 50 50 75 75 100 100 97 97 90 90 82 121 74 119
Max Lift PD (F) 2.7 5.4 4.5 8.1 6.7 10.8 9.0 11.2 8.9 11.2 8.5 11.2 11.2 11.2 11.2
Suction Line Size (in.) 7/8 7/8 1-1/8 7/8 1-1/8 1-1/8 1-1/8 1-3/8 1-1/8 1-3/8 1-1/8 1-3/8 1-1/8 1-3/8
Suction Ln PD (F) 1.5 3.1 0.8 4.6 1.2 1.6 2.1 0.7 2.5 0.8 2.9 1.0 3.3 1.1
Charge (lb) 15.6 19.0 19.7 20.8 24.1 23.1 26.9 25.1 30.7 26.0 32.8 27.0 34.8 27.9 37.1
#/TR 2.08 2.53 2.63 2.77 3.21 3.08 3.59 3.35 4.09 3.47 4.37 3.60 4.64 3.73 4.95
C A S 1 2 1
TC 113.1,
SC 7.1°F
Liquid Line Size (in.) 1/2 1/2 5/8 1/2 5/8 1/2 5/8 1/2 5/8 1/2 5/8 5/8 5/8
Liquid PD (°F) 0.9 1.9 0.5 2.8 0.8 3.8 1.0 4.7 1.3 5.7 1.6 1.8 2.1
Max Lift (ft) 25 40 50 28 54 34 68 22 65 11 63 59 55
Max Lift PD (F) 2.9 5.0 4.5 5.0 5.0 6.5 6.4 6.5 6.4 6.5 6.5 6.4 6.4
Suction Line Size (in.) 7/8 1-3/8 1-3/8 1-1/8 1-3/8 1-1/8 1-3/8 1-1/8 1-3/8 1-1/8 1-3/8 1-1/8 1-3/8 1-1/8 1-3/8
Suction Ln PD (F) 2.4 1.2 1.2 1.8 0.6 2.4 0.9 3.1 1.1 3.7 1.3 4.3 1.5 4.9 1.7
Charge (lb) 15.7 18.0 20.0 19.8 23.1 21.6 26.1 23.6 29.2 25.5 32.3 34.1 35.3 36.9 38.4
#/TR 1.67 1.89 2.09 2.10 2.45 2.29 2.77 2.50 3.10 2.71 3.43 3.62 3.75 3.92 4.08
C A S 1 5 1
TC 146.1,
SC 3.9°F
Liquid Line Size (in.) 5/8 5/8 3/4 5/8 3/4 5/8 3/4 5/8 3/4 5/8 3/4 5/8 3/4 3/4 7/8
Liquid PD (°F) 0.4 0.8 0.4 1.2 0.6 1.6 0.8 2.0 1.1 2.4 1.1 2.8 1.5 1.7 0.6
Max Lift (ft) 23 16 23 10 18 28 38 21 36 14 35 9 30 25 43
Max Lift PD (F) 1.8 1.84 1.84 1.8 1.8 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3
Suction Line Size (in.) 1-5/8b1-5/8b1-5/8b1-1/8 1-3/8 1-3/8 1-3/8 1-5/8 1-3/8 1-5/8 1-3/8 1-5/8 1-3/8 1-5/8
Suction Ln PD (F)
(Cap Red) 0.1 0.2 0.2 3 . 3 (–2.3%) 1.2 1.6 2.0 0.8 2 . 4 (–0.7%) 1.0 2 . 8 (–1.4%) 1.2 3 . 2 (–2.1%) 1.3
Charge (lb) 35.1 38.4 40.9 37.6 41.8 41.1 46.1 44.2 51.6 47.3 56.1 50.3 60.6 63.4 76.9
#/TR 3.10 3.99 3.62 3.09 3.44 3.38 3.79 3.64 4.24 3.89 4.61 4.14 4.98 5.21 6.32
NOTE(S):
a See Legend for Tables 8 and 9 on page 9.
b AHRI ratings as listed are only valid with the piping diameters specified.

CAS-072-153-01SI Rev. A Specifications subject to change without notice. 9
Suction Riser
A suction riser condition exists when the outdoor unit is lo-
cated above the indoor (evaporator) unit and suction vapor
must flow vertically up to return to the compressor. Oil return
is a concern when the suction tube size is too large to pro-
duce the minimum refrigerant velocity to ensure oil return at
minimum load conditions.
Check Table 10 for maximum suction tube size for
CAS units at minimum load conditions. Consider suction
speed riser (reduced tube size for vertical segment only) or
double suction riser arrangement if the planned suction tube
size does not provide necessary minimum flow-rates for this
riser.
OUTDOOR UNIT ABOVE EVAPORATOR COIL
This installation will have at least one suction riser segment.
If the vertical elevation difference is less than 20 ft (6.1 m)
linear feet and requires only one or two segments, consider
a speed riser selection for Circuit 1; use the line marked VA-
POR RISER REQUIRED; NOT GREATER THAN 20 FT
(6.1 M). See Fig. 4. Tube S is the horizontal line size; tube A
is the reduced diameter riser size.
Fig. 4 — Suction Line Piping - Speed Riser
If the vertical elevation difference is greater than 20 ft
(6.1 m) linear feet or requires more than two short lift seg-
ments, select the Circuit 1 suction line size from Double
Suction Riser lines data under VAPOR RISER GREATER
THAN 20 FT (6.1 M). See Fig. 5. Tube S is the horizontal
line size. Tube A is the reduced diameter riser size without
bottom trap; Tube B is the parallel riser size with bottom oil
trap.
Outdoor Unit BELOW Evaporator Coil and No Verti-
cal Riser Segments
Select Circuit 1 suction line size from NO VAPOR RISER
line.
Vertical Separation (outdoor unit above indoor unit)
Vertical elevation difference of 200 ft (60 m) is permitted
when the outdoor unit (CAS072/091/121/151 or
CAS123/153) is located above the indoor unit.
Table 9 — CAS123/153 Piping Recommendations (Dual-Circuit)a,b
NOTE(S):
a See Legend for Tables 8 and 9 on page 9.
b CAS123/153 units require TWO sets of refrigeration piping.
MODEL &
NOMINAL
CAPACITY
LINEAR LINE (FT) 0 - 24 25 - 49 50 - 74 75 - 99 100 - 124 125 - 149 150 - 174 175 - 200
EQUIV. LINE (FT) 0 - 37 38 - 74 75 - 112 113 - 149 150 - 187 188 - 224 225 - 262 263 - 300
C A S 1 2 3
TC 55.9
Each,
SC 12.7°F
Liquid Line Size (in.) 3/8 3/8 3/8 3/8 1/2 3/8 1/2 3/8 1/2 1/2 5/8 1/2 5/8
Liquid PD (°F) 1.4 2.7 5.5 5.5 0.9 6.9 1.1 8.2 1.4 1.6 0.5 1.8 0.5
Max Lift (ft) 25 50 75 82 100 66 125 49 133 130 144 128 144
Max Lift PD (F) 3.4 6.8 10.2 12.1 9.0 12.1 11.2 12.1 12.1 12.1 12.1 12.1 12.1
Suction Line Size (in.) 3/4 7/8 7/8 7/8 1-1/8 7/8 1-1/8 1-1/8 1-1/8 1-1/8
Suction Ln PD (F)
(Cap Red) 1.4 1.2 1.8 2 . 5
(-0.8%) 0.8 3 . 1
(-1.9%) 0.9 1.1 1.3 1.5
Charge (lb) 9.0 10.0 11.0 12.1 15.7 13.1 17.7 14.9 19.6 21.5 28.2 23.5 31.0
#/TR 0.73 0.81 0.89 0.97 1.27 1.05 1.42 1.20 1.58 1.74 2.27 1.89 2.50
C A S 1 5 3
TC 69.8
Each,
SC 14.2°F
Liquid Line Size (in.) 3/8 3/8 3/8 3/8 1/2 3/8 1/2 1/2 1/2 5/8 1/2 5/8
Liquid PD (°F) 2.1 4.1 6.2 8.2 1.5 10.3 1.8 2.2 2.6 0.7 2.9 0.8
Max Lift (ft) 25 50 75 69 155 42 125 145 140 163 135 162
Max Lift PD (F) 4.0 8.1 12.1 13.6 9.4 13.6 11.7 13.6 13.6 13.6 13.6 13.6
Suction Line Size (in.) 1-3/8c
c AHRI ratings as listed are only valid with the piping diameters specified.
1-3/8c7/8 1-1/8 1-1/8 1-1/8 1-1/8 1-1/8 1-1/8
Suction Ln PD (F)
(Cap Red) 0.3 0.6 2 . 9 (-1.5%) 0.8 1.1 1.4 1.6 1.9 2 . 2 (-0.3%) 0.7
Charge (lb) 16.5 17.9 19.0 19.5 20.6 23.7 21.8 25.7 27.6 29.5 36.2 31.5 39.0
#/TR 1.44 1.56 1.52 1.56 1.65 1.90 1.74 2.05 2.21 2.36 2.89 2.52 3.12
LEGEND FOR TABLES 8 AND 9
#/TR —Charge to unit capacity ratio, lbs per ton (at 45°F SST,
95°F ODA)
Cap Red —Capacity reduction caused by suction line pressure
drop GT 2°F
Liquid PD (°F) — Liquid line pressure drop, saturated temperature, °F
Max Lift —Maximum liquid lift (Indoor unit ABOVE outdoor unit
only), at maximum permitted pressure drop.
Max Lift PD (F) — Pressure drop including Maximum liquid lift value
SC — Sub-cooling, °F (at liquid line valve)
Table 10 — CAS Maximum Suction Pipe Size
MODEL AND UNIT SIZE MAXIMUM TUBE SIZE (in.)
CAS072 1-1/8
CAS091 1-1/8
CAS121 1-5/8
CAS151 2-1/8
CAS123 1-3/8
CAS153 1-5/8
Condensing
Unit
20-ft (6.1 m)
max
A
A - Suction Riser With Trap
LEGEND
S - Suction Line to Condensing Unit
S

10 Specifications subject to change without notice. CAS-072-153-01SI Rev. A
Fig. 5 — Suction Line Piping - Double Riser
Step 5 — Complete Refrigerant Piping
Connections
PROVIDE SAFETY RELIEF
If local codes dictate an additional safety relief device, pur-
chase locally and install locally. Installation will require the
recovery of the factory shipping charge before the factory
tubing can be cut and the supplemental relief device is
installed.
Model CAS123/153 has two separate refrigeration systems.
If required, each circuit will require a field-supplied/installed
supplemental relief device.
CHECK CAS MODEL WITH EVAPORATOR COIL
CONNECTIONS
Confirm before installation of unit that the evaporator coil
connections are consistent with this CAS model. See
Table 3 on page 3.
INSULATE SUCTION LINES
Apply closed-cell tubular insulation to all suction lines be-
tween evaporator coil connection and CAS unit’s suction
service valve.
CAS123/153 PIPING CONNECTIONS
The CAS123/153 unit’s two circuits are designated Circuit 1
and Circuit 2. Circuit 1 is controlled by the thermostat’s Y1
and Y3 contact and will be the first circuit on and last circuit
off. Circuit 2 is controlled by the thermostat’s Y2 (or TC2)
contact and this circuit is always the “lag” circuit.
See Fig. 6 for location of Circuit 1 and Circuit 2 service
valves and field piping connections. Circuit 1 is on the right-
hand side of the service valve compartment; Circuit 2 is on
the left.
When a single piece evaporator coil with two separate cir-
cuits is connected to a CAS123/153, the lower coil circuit
should be connected to the CAS123/153 unit’s Circuit 1 so
that the evaporator’s lower coil segment is first-on/last-off
(to avoid re-evaporation of condensate on dry lower coil
segments).
Fig. 6 — CAS123/153 Service Valve Locations
Plan the Circuit 1 and Circuit 2 tubing segments carefully,
mark each segment and check constantly as piping sys-
tems are assembled to avoid piping errors.
The CAS123/153 unit cannot be field-piped as a single-
circuit/tandem system.
FINAL TUBING CHECK — CAS123/153
Before completing the field piping connections to the
CAS123/153 unit service valves, confirm that the suction
line to the indoor coil’s first-on/last-off circuit (and its com-
panion liquid line) are correctly identified as Circuit 1 use
for the CAS123/153 unit. If a suction riser is required, it
must be in Circuit 1.
Connecting F*S/H to CAS123/153
The F*X (6 to 10 tons) and the F*S/H (12.5 tons) fan coils
are a face-split coil design that also has its circuits designat-
ed as 1 and 2. See Table 11 and Fig. 7. Note that the lower
coil segment changes as the arrangement of the F*X/F*S/H
changes. In a vertical arrangement, the F*S/H unit’s lower
coil segment is segment 2; this segment should be connect-
ed to the CAS123/153 unit’s Circuit 1. In a horizontal ar-
rangement, the F*X/F*S/H unit’s lower segment is now seg-
ment 1; this segment should be connected to the
CAS123/153 unit’s Circuit 1.
Note that refrigerant suction piping should be insulated.
INSTALL FILTER DRIER(S) AND MOISTURE
INDICATOR(S)
Every unit MUST have a filter drier in the liquid line.
CAS123/153 models require two filter driers (one in each
liquid line). Locate the filter drier(s) at the indoor unit, close
to the evaporator coil’s thermal expansion valve (TXV)
inlets.
The CAS units include one (CAS072/091/121/151) or two
(CAS123/153) R-410A-duty filter drier(s), shipped in cartons
attached to the unit basepan (see Table 12). Remove the fil-
ter drier(s) and prepare to install in the liquid line(s) at the
evaporator coil. Do not remove connection fitting plugs until
ready to connect and braze the filter drier into the liquid line
position.
IMPORTANT: DO NOT BURY REFRIGERANT LINES.
IMPORTANT: A refrigerant receiver is not provided with
the unit. Do not install a receiver.
From
Evaporator
A
A - Suction Riser Without Trap
B - Suction Riser With Trap
S - Suction Line to Condensing Unit
LEGEND
B
S
S
Table 11 — F*X / F*S/H Arrangement Details
F*X / F*S/H
ARRANGEMENT
COOLING
STAGE
F*X / F*S/H
COIL
SEGMENT
CONNECT TO
CAS123/153
Vertical Y1, Y2, and Y3 2 Circuit 1
Y2 and Y3 1 Circuit 2
Horizontal Y2 and Y3 1 Circuit 1
Y1, Y2, and Y3 2 Circuit 2
Circuit 2
Connections
Circuit 1
Connections
CKT
1CKT
2

CAS-072-153-01SI Rev. A Specifications subject to change without notice. 11
Installation of liquid line moisture indicating sight glass in
each circuit is recommended. Locate the sight glass(es) be-
tween the outlet of the filter drier and the TXV inlet.
Refer to Table 13 for recommendations on refrigeration
specialties.
Fig. 7 — Typical Evaporator Coil Connections
(F*X / F*S/H)
In some applications, depending on space and convenience
requirements, it may be desirable to install 2 filter driers and
sight glasses in a single circuit application. One filter drier
and sight glass may be installed at A locations (see Fig. 8)
or 2 filter driers and sight glasses may be installed at B loca-
tions (see Fig. 8 and 9).
Select the filter drier for maximum unit capacity and mini-
mum pressure drop. Complete the refrigerant piping from
the indoor unit to the outdoor unit before opening the liquid
and suction lines at the outdoor unit.
INSTALL LIQUID LINE SOLENOID VALVE
It is recommended that a solenoid valve be placed in the
main liquid line (see Fig. 8 and 9) between the condensing
unit and the evaporator coil. Locate the solenoid valve at the
outlet end of the liquid line, near the evaporator coil connec-
tions, with flow direction arrow pointed at the evaporator
coil. Refer to Table 13. (A liquid line solenoid valve is re-
quired when the liquid line length exceeds 75 ft [23 m].) This
valve prevents refrigerant migration (which causes oil dilu-
tion) to the compressor during the off cycle, at low outdoor
ambient temperatures. Wire the solenoid in parallel with the
compressor contactor coil (see Fig. 8 and 9). This means of
electrical control is referred to as solenoid drop control.
Fig. 8 — Location of Sight Glass(es) and Filter Driers
Typical CAS072/091/121/151 Systems
Fig. 9 — Location of Sight Glasses and Filter Driers
Typical CAS123/153 Systems
Table 12 — R-410A-Duty Filter Drier(s)
MODEL SIZE QTY LIQUID LINE
OD (in.)
DESICCANT
VOLUME
PART
NUMBER
REF.
CAS072 1 1/2 8 cu in. KH43LG091
CAS091 1 1/2 16 cu in. KH43LG085
CAS121 1 1/2 16 cu in. KH43LG085
CAS151 1 1/2 30 cu in. KH43LG087
CAS123 2 3/8 8 cu in. KH43LG091
CAS153 2 1/2 16 cu in. KH43LG085
Table 13 — Refrigerant Specialties Part Numbers
LIQUID
LINE
SIZE
(in.)
LIQUID LINE
SOLENOID
VALVE
(LLSV)
LLSV COIL SIGHT
GLASS
FILTER
DRIER
3/8 EF680033 EF680037 KM680008 Provided with
unit, see
Table 12
1/2 EF680035 EF680037 KM680004
5/8 EF680036 EF680037 KM680005
Condensate Drain Connection
Condensate Drain
Connection
Suction-Vapor
Connection
Liquid Line
Connection
Horizontal Installation
Coil Segment 1
Coil Segment 2
First On/Last Off = 2
Coil Segment 2
Coil Segment 1
First On/Last Off = 1
Vertical Installation
INDOOR
COIL CKT 2
AIRFLOW
INDOOR
COIL CKT 1
AIRFLOW
15 DIAMS
MIN 10
DIAMS
8 DIAMS
MIN
TXV
SENSING
BULB
EQUALIZER LINE
SIGHT GLASS
A LOCATION
SIGHT
GLASSES
B LOCATION
TXV
CKT 2
FILTER DRIER
A LOCATION
FILTER
DRIERS
B LOCATION
FLOW
TXV
SENSING
BULB
TXV
CKT 1
8 DIAMS
MIN
15 DIAMS
MIN 10
DIAMS
Single Circuit Coil Piping Configuration
For Single Compressor Condensing Units
Dual Circuit Coil Piping Configuration
For Single Compressor Condensing Units
15 DIAMS
MIN 10
DIAMS
8 DIAMS
MIN
INDOOR
COIL CKT
AIRFLOW
TXV
SENSING
BULB
EQUALIZER LINE
SIGHT GLASS
A LOCATION
TXV
FILTER DRIER
A LOCATION
LIQUID LINE
SOLENOID
VALVE
FLOW
LIQUID LINE
SOLENOID
VALVE
AIRFLOW
SUCTION
CIRCUIT 2
SUCTION
CIRCUIT 1
AIRFLOW
15 DIAMS
MIN 10
DIAMS
8 DIAMS
MIN
TXV
SENSING
BULB
EQUALIZER LINE
SIGHT
GLASSES
TXV
CKT 2
FILTER
DRIERS
LIQUID LINE
SOLENOID VALVE
CIRCUIT 2
FLOW
LIQUID LINE
SOLENOID VALVE
CIRCUIT 1
FLOW
TXV
SENSING
BULB
TXV
CKT 1
8 DIAMS
MIN
15 DIAMS
MIN 10
DIAMS
Dual Circuit Coil Piping Configuration
For Two Circuit Condensing Units

12 Specifications subject to change without notice. CAS-072-153-01SI Rev. A
Solenoid Drop Control Wiring
Control the power to the liquid line solenoid through a Sole-
noid Valve Relay (SVR) in all units. Use part number
HN61PC005 (field-supplied, installed). CAS072/091/121/151
unit requires one SVR; CAS123/153 unit requires two relays.
A unit with two liquid line solenoid valves also requires a
separate control power transformer for the liquid solenoid
valve loads. Select TRAN3 transformer part number ac-
cording to unit power supply.
Mount the SVR (and transformer TRAN3 when used) in unit
control box. Connect per wiring schematic label on unit.
Evaporator Capacity Control Liquid Line Solenoid
Valve
Many older unit designs included automatic capacity con-
trols that sensed changes in suction pressure and could in-
crease or decrease compressor capacity automatically as
the evaporator load changed. Control systems were used
on these units that had the thermostat’s second stage con-
tacts control a capacity control liquid line solenoid valve to
open or shutoff a portion of the evaporator surface without
any direct connection to the compressor circuit.
This form of system capacity staging control is not possible
with CAS models. If this installation is a retrofit for a unit that
included automatic pressure-operated unloading, check the
existing thermostat and liquid solenoid valve. When found,
convert the evaporator second stage solenoid control into a
drop-solenoid control. Use the two SVR relays and trans-
former as required on CAS123/153 models (above); wire
the SVRs and transformer per two solenoid valve systems.
SELECTING AN ACCUMULATOR
Because all CAS models use scroll compressors, an accu-
mulator is not required. If an accumulator is to be added,
check the accumulator manufacturer’s literature carefully for
indication of its suitability for use with R-410A; look for mini-
mum working pressure of 200 psig (1380 kPa). Select the
accumulator first on the basis of its cataloged minimum ca-
pacity (tons) to ensure oil return from the accumulator, then
on tube size or holding capacity.
MAKE PIPING CONNECTIONS
Piping connections at the CAS unit are ball valves with stub
tube extensions. Do not open the unit service valves until all
interconnecting tube brazing has been completed. The stub
tube connections include 1/4-in. SAE service fittings with
Schrader valve cores (see Fig. 10). Before making any
brazed connections to the unit service valves, remove both
Schrader valve caps and cores and save for re-installation.
Connect a source for nitrogen to one of these service fittings
during tube brazing to prevent the formation of copper
oxides inside the tubes at brazed joints.
When connecting the field tubing to the CAS service valves,
wrap the valves in wet rags to prevent overheating.
Pressure-test all joints from outdoor unit connections over to
the evaporator coil, using nitrogen as pressure and with
soap-and-bubbles.
When pressure-testing is completed, remove the nitrogen
source at the outdoor unit service valves and re-install the
two Schrader valve cores. Torque the cores to 2 to 3 in-lbs
(23 to 34 N-cm).
Fig. 10 — Typical Piping Connection Assembly
EVACUATION/DEHYDRATION
Evacuate and dehydrate the connected refrigeration sys-
tem(s) (excluding the CAS unit) to 500 microns using a two-
stage vacuum pump attached to the service ports outside
the CAS service valves, following description in GTAC II,
Module 4, System Dehydration.
This unit is designed for use with R-410A refrigerant. Do not
use any other refrigerant in this system.
R-410A refrigerant is provided in pink (rose) colored cylin-
ders. These cylinders are available with and without dip
tubes; cylinders with dip tubes will have a label indicating
this feature. For a cylinder with a dip tube, place the cylinder
in the upright position (access valve at the top) when remov-
ing liquid refrigerant for charging. For a cylinder without a
dip tube, invert the cylinder (access valve on the bottom)
when removing liquid refrigerant.
Because R-410A refrigerant is a blend, it is strongly rec-
ommended that refrigerant always be removed from the
cylinder as a liquid. Admit liquid refrigerant into the system
in the discharge line. If adding refrigerant into the suction
line, use a commercial metering/expansion device at the
gauge manifold; remove liquid from the cylinder, pass it
through the metering device at the gauge set and then
pass it into the suction line as a vapor. Do not remove
R-410A refrigerant from the cylinder as a vapor.
PRELIMINARY CHARGE
Before starting the unit, charge R-410A liquid refrigerant into
the high side of each CAS circuit through the liquid service
valve(s). The amount of refrigerant added must be at least
80% of the operating charge listed in Tables 5 or 6 for
LINEAR line length LESS the factory charge quantity (if fac-
tory shipping charge has not been removed). See example
below.
Allow high and low side pressures to equalize. If pressures
do not equalize readily, charge R-410A vapor (using special
service manifold with expansion device) into the suction line
service port for the low side of system to assure charge in
the evaporator. Refer to GTAC II, Module 5, Charging,
MODEL QTY
LSV
RELAY SVR QTY
- PART NUMBER
TRAN3 PRIMARY V:
PART NUMBER
CAS072/091/
121/151
1 1 — HN61PC005 N/R
2 2 — HN61PC005 208/230V: HT01BD202
CAS123/153 2 2 — HN61PC005 460V: HT01BD702
575V: HT01BD902
LEGEND
LSV — Liquid Solenoid Valve
SVR — Solenoid Valve Relay
N/R — Not Required
WARNING
UNIT OPERATION AND SAFETY HAZARD
Failure to follow this warning could cause personal
injury, death and/or equipment damage.
R-410A refrigerant systems operate at higher pressures
than standard R-22 systems. Do not use R-22 service
equipment or components on R-410A refrigerant
equipment.
Factory
High-Flow
Access Port
Service Valve
with Stem Cap
Field Service
Access Port
(Schrader Core)
Sweat
Connection

CAS-072-153-01SI Rev. A Specifications subject to change without notice. 13
Recover, Recycling, and Reclamation for liquid charging
procedures.
Example:
CAS121
60 ft (18.3 m) linear line length
Equivalent line length 90 ft (27.4 m)
Liquid Lift: 20 ft (6.1 m)
Select line sizes from Table 8 (CAS072/091/121/151):
Liquid 1/2 in.
Suction 1-1/8 in.
Charge 23.1 lb (at 75 ft linear length)
80% of Operating Charge:
0.80 x 23.1 = 18.5 lb
Factory Shipping Charge: 9 lb
Field-Charge quantity: 18.5 – 9.0 = 9.5 lb
Step 6 — Install Accessories
Accessories requiring modifications to unit wiring should be
completed now. These accessories may include Winter
Start controls and Low Ambient controls. Refer to the in-
structions shipped with the accessory.
Step 7 — Complete Electrical Connections
NOTE: Check all factory and field electrical connections for
tightness. Field-supplied wiring shall conform with the limita-
tions of 63°F (33°C) rise.
FIELD POWER SUPPLY
If equipped with optional Powered Convenience Outlet: The
power source leads to the convenience outlet’s transformer
primary are not factory connected. Installer must connect
these leads according to required operation of the conve-
nience outlet. If an always-energized convenience outlet op-
eration is desired, connect the source leads to the line side
of the unit-mounted disconnect. (Check with local codes to
ensure this method is acceptable in your area.) If a de-
energize via unit disconnect switch operation of the conve-
nience outlet is desired, connect the source leads to the
load side of the unit disconnect. On a unit without a unit-
mounted disconnect, connect the source leads to compres-
sor contactor C and indoor fan contactor IFC pressure lugs
with unit field power leads.
Field power wires are connected to the unit at line-side
pressure lugs on compressor contactor C and TB1 (see wir-
ing diagram label for control box component arrangement)
or at factory-installed option non-fused disconnect switch.
Max wire size is #4 AWG (copper only).
NOTE: TEST LEADS — Unit may be equipped with short
leads (pigtails) on the field line connection points on contac-
tor C or optional disconnect switch. These leads are for fac-
tory run-test purposes only; remove and discard before con-
necting field power wires to unit connection points. Make
field power connections directly to line connection pressure
lugs only.
Fig. 11 — Disconnect Switch and Unit
UNITS WITH FACTORY-INSTALLED NON-FUSED
DISCONNECT
The factory-installed option disconnect switch is located in a
weatherproof enclosure located under the main control box.
The manual switch handle is accessible through an opening
in the access panel.
UNITS WITHOUT FACTORY-INSTALLED NON-FUSED
DISCONNECT
When installing units, provide a disconnect switch per NEC
(National Electrical Code) of adequate size. Disconnect siz-
ing data is provided on the unit informative plate. Locate on
unit cabinet or within sight of the unit per national or local
codes. Do not cover unit informative plate if mounting the
disconnect on the unit cabinet.
ALL UNITS
All field wiring must comply with NEC and all local codes.
Size wire based on MCA (Minimum Circuit Amps) on the
unit informative plate. See Fig. 12 for power wiring connec-
tions to the unit contactor and terminal block and equipment
ground.
Provide a ground-fault and short-circuit over-current protec-
tion device (fuse or breaker) per NEC Article 440 (or local
codes). Refer to unit informative data plate for MOCP (Max-
imum Over-current Protection) device size.
All units except 208/230-v units are factory wired for the
voltage shown on the nameplate. If the 208/230-v unit is to
be connected to a 208-v power supply, the control trans-
former must be rewired by moving the black wire with the
1/4-in. female spade connector from the 230-v connection
and moving it to the 208-v 1/4-in. male terminal on the pri-
mary side of the transformer. Refer to unit label diagram for
line-side information.
Affix the crankcase heater warning sticker to the unit discon-
nect switch.
WARNING
ELECTRIC SHOCK HAZARD
Failure to follow this warning could result in personal
injury or death.
Unit cabinet must have an uninterrupted, unbroken
electrical ground to minimize the possibility of personal
injury if an electrical fault should occur. This ground may
consist of electrical wire connected to unit ground lug in
control compartment, or conduit approved for electrical
ground when installed in accordance with NEC;
ANSI/NFPA 70, latest edition (in Canada, Canadian
Electrical Code CSA [Canadian Standards Association]
C22.1), and local electrical codes.
WARNING
FIRE HAZARD
Failure to follow this warning could result in personal
injury, death, or property damage.
Do not connect aluminum wire between disconnect
switch and unit. Use only copper wire. See Fig. 11.
Copper
Wire Only
Electric
Disconnect
Switch
Aluminum
Wire

14 Specifications subject to change without notice. CAS-072-153-01SI Rev. A
Fig. 12 — Power Wiring Connections
CONVENIENCE OUTLETS
Two types of convenience outlets are offered on CAS mod-
els: Non-powered and unit-powered. Both types provide a
125-volt GFCI (ground-fault circuit-interrupter) duplex re-
ceptacle rated at 15-A behind a hinged waterproof access
cover, located on the end panel of the unit. See Fig. 13.
Fig. 13 — Convenience Outlet Location
Non-Powered Type
This type requires the field installation of a general-
purpose 125-volt 15-A circuit powered from a source else-
where in the building. Observe national and local codes
when selecting wire size, fuse or breaker requirements
and disconnect switch size and location. Route 125-v pow-
er supply conductors into the bottom of the utility box con-
taining the duplex receptacle. Maximum continuous cur-
rent for this type of convenience outlet (non-unit powered)
must not exceed 8 Amps.
Unit-Powered Type
A unit-mounted transformer is factory-installed to step down
the main power supply voltage to the unit to 115-v at the du-
plex receptacle. This option also includes a manual switch
with fuse, located in a utility box and mounted on a bracket
behind the convenience outlet; access is through the unit’s
control box access panel. See Fig. 13.
The primary leads to the convenience outlet transformer are
not factory-connected. Selection of primary power source is
a customer-option. If local codes permit, the transformer pri-
mary leads can be connected at the line-side terminals on
the unit-mounted non-fused disconnect switch; this will pro-
vide service power to the unit when the unit disconnect
switch is open. Other connection methods will result in the
convenience outlet circuit being de-energized when the unit
disconnect switch is open. See Fig. 14.
Fig. 14 — Powered Convenience Outlet Wiring
The unit-powered convenience outlet has a 1000 VA rated
transformer. Maximum continuous current must not exceed
8Amps.
Test the GFCI receptacle by pressing the TEST button on
the face of the receptacle to trip and open the receptacle.
Check for proper grounding wires and power line phasing
if the GFCI receptacle does not trip as required. Press the
RESET button to clear the tripped condition.
WARNING
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal
injury or death.
Units with convenience outlet circuits may use multiple
disconnects. Check convenience outlet for power status
before opening unit for service. Locate its disconnect
switch, if appropriate, and open it. Lock-out and tag-out
this switch, if necessary.
11 13
L1 L2 L3
C TB1
208/230-3-60
460-3-60
575-3-60
Units Without Disconnect Option
Units With Disconnect Option
2
4
6
1
3
5
L1
L2
L3
Optional
Disconnect
Switch
Disconnect factory test leads; discard.
Factory
Wiring
Disconnect
per
NEC
Control Box
Access Panel
Pwd-CO
Transformer
Convenience
Outlet
GFCI
Pwd-CO
Fuse
Switch
PRIMARY
CONNECTIONS
UNIT
VOLTAGE
208, 230
460
575
CONNECT
AS
240
480
600
L1: RED + YEL
L2: BLU + GRA
L1: RED
Splice BLU + YEL
L2: GRA
L1: RED
L2: GRA
TRANSFORMER
TERMINALS
H1 + H3
H2 + H4
H1
H2 + H3
H4
H1
H2

CAS-072-153-01SI Rev. A Specifications subject to change without notice. 15
Fuse on power type: The factory fuse is a Bussman1“Fuse-
tron” T-15, non-renewable screw-in (Edison base) type plug
fuse.
Installing Weatherproof Cover
A weatherproof while in use cover for the factory installed
convenience outlets is now required by UL standards. This
cover cannot be factory mounted due its depth; it must be
installed at unit installation. For shipment, the convenience
outlet is covered with a blank cover plate.
The weatherproof cover kit is shipped in the unit’s control
box. The kit includes the hinged cover, a backing plate and
gasket.
DISCONNECT ALL POWER TO UNIT AND
CONVENIENCE OUTLET.
Remove the blank cover plate at the convenience outlet;
discard the blank cover.
Loosen the two screws at the GFCI duplex outlet, until ap-
proximately 1/2-in. (13 mm) under screw heads are ex-
posed. Press the gasket over the screw heads. Slip the
backing plate over the screw heads at the keyhole slots and
align with the gasket; tighten the two screws until snug (do
not overtighten).
Mount the weatherproof cover to the backing plate as
shown in Fig. 15. Remove two slot fillers in the bottom of the
cover to permit service tool cords to exit the cover. Check
for full closing and latching.
Fig. 15 — Weatherproof Cover Installation
ALL UNITS
Voltage to compressor terminals during operation must be
within voltage range indicated on unit nameplate. See
Tables 14-17 (on pages 16-17). On 3-phase units, voltag-
es between phases must be balanced within 2% and the
current within 10%. Use the formula shown in the legend
for Tables 14-17, Note 4 (see page 17) to determine the
percent of voltage imbalance. Operation on improper line
voltage or excessive phase imbalance constitutes abuse
and may cause damage to electrical components. Such
operation would invalidate any applicable unit warranty.
FIELD CONTROL WIRING
The CAS unit control voltage is 24 v. See Appendix B Wiring
Diagrams (on pages 35-46) for typical field control connec-
tions and the unit’s label diagram for field-supplied wiring
details. Route control wires to the CAS unit through the
opening in unit’s end panel to the connections terminal
board in the unit’s control box.
Remainder of the system controls connection will vary ac-
cording to the specific construction details of the indoor
section (air handler or packaged fan coil). Figures 16
(CAS072/091/121/151) and 17 (CAS123/153) depict typi-
cal connections to a F*X / F*S/H fan coil unit. Plan for field
connections carefully and install control wiring correctly
per the project plan. Additional components and supple-
mental transformer accessory may be required.
The CAS unit requires an external temperature control de-
vice. This device can be a thermostat (field-supplied).
THERMOSTAT
Install a field-installed thermostat according to its installation
instructions. For typical thermostat connections, see Fig. 16
(CAS072/091/121/151) and 17 (CAS123/153). Locate the
field-installed thermostat on a solid wall in the conditioned
space to sense average temperature in accordance with the
thermostat installation instructions.
Fig. 16 — Single Circuit Thermostat Connections —
CAS072/091/121/151
CAS072/091/121/151 is a single circuit, two-stage cooling
unit. Select a two-stage cooling thermostat.
The CAS123/153 is a dual-circuit, three-stage cooling unit.
Select a three-stage cooling thermostat.
Select a thermostat cable or equivalent single leads of dif-
ferent colors with minimum of five leads for CAS123/153 or
CAS072/091/121/151 unit. Check the thermostat installation
instructions for additional features which might require addi-
tional conductors in the cable.
1. Bussmann and Fusetron are trademarks of Cooper Technologies
Company.
WARNING
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal
injury or death.
Using unit-mounted convenience outlets: Units with unit-
mounted convenience outlet circuits will often require
that two disconnects be opened to de-energize all power
to the unit. Treat all units as electrically energized until
the convenience outlet power is also checked and de-
energization is confirmed. Observe National Electrical
Code Article 210, Branch Circuits, for use of
convenience outlets.
Cover — While-In-Use
Weatherproof
Baseplate For
GFCI Receptacle
Gasket
GFCI Receptacle
Not Included
TOP
TOP
TOP
WET LOCA
TIONS
WETLOCATIONS
Field Wiring
LEGEND
NOTES:
1. Connect only if thermostat requires 24-vac power source.
2. Connect W1 and W2 if supplemental heaters are installed.
3. Y2 connection for Single Circuit/2-Stage units only.
(Note 1)
(Note 2)
(Note 3)
(Note 2)

16 Specifications subject to change without notice. CAS-072-153-01SI Rev. A
For wire runs up to 50 ft (15 m), use no. 18 AWG (American
Wire Gage) insulated wire (35°C minimum). For 50 to 75 ft.
(15 to 23 m), use no. 16 AWG insulated wire (35°C mini-
mum). For over 75 ft (23 m), use no. 14 AWG insulated wire
(35°C minimum). All wire sizes larger than no. 18 AWG can-
not be directly connected to the thermostat and will require
a junction box and splice at the thermostat.
Fig. 17 — Dual Circuit Thermostat Connections —
CAS123/153
EXTERNAL DEVICES
The CAS control transformers provide 24-v NEC Class 2
power sources to energize external control devices. These
devices will include the indoor fan motor contactor (or con-
trol relay) or the unit control board in the fan coil unit. These
devices may also include liquid line solenoid valve (two on
CAS123/153 model), economizer control relay, supplemen-
tal electric heater contactors or control relays and other de-
vices selected by system designer.
Control transformer TRAN1 provides control power through
terminal R to C on the field connection terminal strip TB for
supply fan motor interlock. This source may also be used to
energize economizer control relay and electric heater con-
tactors or relays. Maximum available power is 20 va. Check
concurrent loadings by external control devices. If the maxi-
mum concurrent loading exceeds 20 va, purchase and in-
stall the accessory Transformer-Relay package (available
for 208/230 and 460-v units).
CAS123/153 Only
Control transformer TRAN3 provides control power through
terminals A1 (9) and A2 (10) to C for liquid line solenoids.
Maximum available power is 75 va. These outputs are
switched ON/OFF by the Solenoid Valve Relays.
(Note 1)
(Note 2)
(Note 3)
(Note 3)
1. Typical multi-function marking. Follow manufacturer’s configuration instructions to select Y2.
2. Connect only if thermostat requires 24-vac power source.
3. Connect W1and W2 if supplemental heaters are installed.
Field Wiring
LEGEND
NOTES:
Table 14 — CAS072/091/121/151 Single Circuit Electrical Data without Powered Convenience Outleta
NOTE(S):
a See Legend and Notes for Tables 14-17
UNIT SIZE
NUMBER
OF
STAGES
NOMINAL
POWER
SUPPLY
V-Ph-Hz
VOLTAGE
RANGE
COMPRESSOR OFM POWER SUPPLY DISCONNECT SIZE
No. 1 No. 2
Min Max RLA LRA RLA LRA Qty FLA (ea) MCA
Fuse or
HACR
Brkr
FLA LRA
CAS072*G
2 575-3-60 518 633 6.3 55 — — 2 0.7 10 15 9 59
2 208/230-3-60 187 253 17.5 136 — — 2 1.5 25/25 30/30 24/24 142/142
2 460-3-60 414 506 8.4 66 — — 2 0.8 13 20 12 70
CAS091*G
2 575-3-60 518 633 9.9 78 — — 2 0.7 14 20 13 82
2 208/230-3-60 187 253 26.8 164 — — 2 1.5 37/37 60/60 34/34 170/170
2 460-3-60 414 506 12.6 100 — — 2 0.8 18 25 16 104
CAS121*M
2 575-3-60 518 633 11.4 94 — — 2 0.7 16 25 15 98
2 208/230-3-60 187 253 33.2 240 — — 2 1.5 45/45 60/60 42/42 246/246
2 460-3-60 414 506 15.1 130 — — 2 0.8 21 30 19 134
CAS151*M
2 575-3-60 518 633 6.6 55 6.6 55 2 0.7 17 20 17 114
2 208/230-3-60 187 253 19.6 136 19.6 136 2 1.5 48/48 60/60 49/49 278/278
2 460-3-60 414 506 8.2 66 8.2 66 2 0.8 21 25 21 136

CAS-072-153-01SI Rev. A Specifications subject to change without notice. 17
Table 15 — CAS072/091/121/151 Single Circuit Electrical Data with Powered Convenience Outleta
UNIT SIZE
NUMBER
OF
STAGES
NOMINAL
POWER
SUPPLY
V-Ph-Hz
VOLTAGE
RANGE
COMPRESSOR OFM POWER SUPPLY DISCONNECT SIZE
No. 1 No. 2
Min Max RLA LRA RLA LRA Qty FLA (ea) MCA
Fuse or
HACR
Brkr
FLA LRA
CAS072*G
2 575-3-60 518 633 6.3 55 — — 2 0.7 11 15 11 61
2 208/230-3-60 187 253 17.5 136 — — 2 1.5 30/30 45/45 29/29 147/147
2 460-3-60 414 506 8.4 66 — — 2 0.8 15 20 14 72
CAS091*G
2 575-3-60 518 633 9.9 78 — — 2 0.7 16 25 15 84
2 208/230-3-60 187 253 26.8 164 — — 2 1.5 42/42 60/60 40/40 175/175
2 460-3-60 414 506 12.6 100 — — 2 0.8 20 30 19 106
CAS121*M
2 575-3-60 518 633 11.4 94 — — 2 0.7 18 25 17 100
2 208/230-3-60 187 253 33.2 240 — — 2 1.5 50/50 60/60 47/47 251/251
2 460-3-60 414 506 15.1 130 — — 2 0.8 23 30 22 136
CAS151*M
2 575-3-60 518 633 6.6 55 6.6 55 2 0.7 18 20 19 116
2 208/230-3-60 187 253 19.6 136 19.6 136 2 1.5 52/52 60/60 54/54 283/283
2 460-3-60 414 506 8.2 66 8.2 66 2 0.8 23 30 23 138
NOTE(S):
a See Legend and Notes for Tables 14-17
Table 16 — CAS123/153*T Two Circuit Electrical Data without Powered Convenience Outleta
UNIT SIZE
NUMBER
OF
STAGES
NOMINAL
POWER
SUPPLY
V-Ph-Hz
VOLTAGE
RANGE
COMPRESSOR OFM POWER SUPPLY DISCONNECT SIZE
No. 1 No. 2
Min Max RLA LRA RLA LRA Qty FLA (ea) MCA
Fuse or
HACR
Brkr
FLA LRA
CAS123*T
3 575-3-60 518 633 6.4 48 5.8 39 2 0.7 16 20 16 91
3 208/230-3-60 187 253 16.4 110 15.6 110 2 1.5 40/40 50/50 40/40 226/226
3 460-3-60 414 506 6.8 55 7.7 52 2 0.8 18 25 19 111
CAS153*T
3 575-3-60 518 633 6.6 55 6.6 55 2 0.7 17 20 17 114
3 208/230-3-60 187 253 17.5 136 19.6 136 2 1.5 45/45 60/60 46/46 278/278
3 460-3-60 414 506 8.4 66 8.2 66 2 0.8 21 25 21 136
NOTE(S):
a See Legend and Notes for Tables 14-17
Table 17 — CAS123/153*T Two Circuit Electrical Data with Powered Convenience Outleta
NOTE(S):
a See Legend and Notes for Tables 14-17
UNIT SIZE
NUMBER
OF
STAGES
NOMINAL
POWER
SUPPLY
V-Ph-Hz
VOLTAGE
RANGE
COMPRESSOR OFM POWER SUPPLY DISCONNECT SIZE
No. 1 No. 2
Min Max RLA LRA RLA LRA Qty FLA (ea) MCA
Fuse or
HACR
Brkr
FLA LRA
CAS123*T
3 575-3-60 518 633 6.4 48 5.8 39 2 0.7 17 20 18 93
3 208/230-3-60 187 253 16.4 110 15.6 110 2 1.5 44/44 60/60 46/46 231/231
3 460-3-60 414 506 6.8 55 7.7 52 2 0.8 21 25 21 113
CAS153*T
3 575-3-60 518 633 6.6 55 6.6 55 2 0.7 18 20 19 116
3 208/230-3-60 187 253 17.5 136 19.6 136 2 1.5 50/50 60/60 52/52 283/283
3 460-3-60 414 506 8.4 66 8.2 66 2 0.8 23 30 23 138

18 Specifications subject to change without notice. CAS-072-153-01SI Rev. A
LEGEND AND NOTES FOR TABLES 14-17
LEGEND
NOTES:
1. The MCA and Fuse values are calculated in accordance with the
NEC Article 440.
2. Motor RLA and LRA values are established in accordance with
Underwriters Laboratories (UL) Standard 1995.
3. The 575-v units are UL, Canada-listed only.
4. Unbalanced 3-Phase Supply Voltage. Never operate a motor
where a phase imbalance in supply voltage is greater than 2%.
Use the following formula to determine the percentage of voltage
imbalance.
Example: Supply voltage is 230-3-60
Determine maximum deviation from average voltage.
(AB) 227-224 = 3 v
(BC) 231-227 = 4 v
(AC) 227-226 = 1 v
Maximum deviation is 4 v.
Determine percent of voltage imbalance.
This amount of phase imbalance is satisfactory as it is below the
maximum allowable 2%.
Step 8 — Wind Baffles for Low Ambient
Control
Units with low ambient control (either as a factory-in-
stalled option or a field-installed accessory) require the
addition of wind baffles to ensure full range low ambient
operation. Material data and dimensions for wind baffles
are included in the Appendix C section, Low Ambient
Control, starting on page 50. Fabricate the wind baffles
and mount per instructions.
PRE-START-UP
System Check
1. The electrical power source must agree with the
unit’s nameplate rating.
2. Check all air handler(s) and other equipment auxil-
iary components. Consult the manufacturer’s instruc-
tions regarding any other equipment connected to
the condensing unit. If the unit has field-installed
accessories, be sure all are properly installed and
correctly wired. If used, the airflow switch must be
properly installed.
3. Check tightness of all electrical connections.
4. Be sure liquid line and low side of the system are
properly leak checked and dehydrated.
5. Be sure the unit is properly charged. See “Prelimi-
nary Charge”, below.
6. Open the liquid line and suction line service valves.
7. The crankcase heater must be firmly attached to the
compressor crankcase. Be sure the crankcase is
warm (heater must be on for 24 hours before starting
compressor).
Turn On Crankcase Heater
Turn on the crankcase heater for 24 hours before starting
the unit to be sure all the refrigerant is out of the oil. To ener-
gize the crankcase heater, proceed as follows:
1. Set the space thermostat set point above the space
temperature so there is no demand for cooling.
2. Close the field disconnect.
Preliminary Charge
Before starting the unit, charge liquid refrigerant into the
high side of the system through the liquid service valve. The
amount of refrigerant added must be at least 80% of the op-
erating charge listed in the Physical Data table (Tables 5
and 6). Allow high and low side pressures to equalize be-
fore starting compressor. If pressure do not equalize readily,
charge vapor on low side of system to assure charge in the
evaporator. Refer to GTAC II, Module 5, Charging, Recover,
Recycling, and Reclamation for liquid charging procedures.
START-UP
The compressor crankcase heater must be on for 24 hours
before start-up. After the heater has been on for 24 hours,
the unit can be started. If no time elapsed since the prelimi-
nary charge step was completed, it is unnecessary to wait
the 24-hour period.
Preliminary Checks
1. Check that electric power supply agrees with unit
nameplate data.
2. Verify that the compressor crankcase heater is
securely in place.
3. Check that the compressor crankcase heater has
been on at least 24 hours.
4. Recheck for leaks using the procedure outlined in the
Pre-Start-Up section, Leak Test and Dehydration. If
any leaks are detected, repair as required. Evacuate
and dehydrate as described in the Leak Test and
Dehydration section.
FLA — Full Load Amps
LRA — Locked Rotor Amps
MOCP — Maximum Over Current Protection
NEC — National Electrical Code
RLA — Rated Load Amps
% Voltage
Imbalance = 100 x max voltage deviation from average voltage
average voltage
AB = 224 v
BC = 231 v
AC = 226 v
Average Voltage = (224 + 231 + 226) =681 = 227
33
% Voltage Imbalance = 100x 4= 1.78%
227
IMPORTANT: If the supply voltage phase imbalance is more than 2%,
contact your local electric utility company immediately.
IMPORTANT: Before beginning Pre-Start-Up or Start-Up,
review Start-Up Checklist at the back of this book. The
Checklist assures proper start-up of a unit and provides a
record of unit condition, application requirements, system
information, and operation at initial start-up.
CAUTION
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage.
Do not attempt to start the condensing unit, even mo-
mentarily, until the following steps have been completed.
Compressor damage may result.
ABC
MOTOR
CAUTION
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage.
Prior to starting compressor, a preliminary charge of
refrigerant must be added to avoid possible compressor
damage.

CAS-072-153-01SI Rev. A Specifications subject to change without notice. 19
5. Ensure that the preliminary charge has been added
as described in the Pre-Start-Up section, Preliminary
Charge.
6. All internal wiring connections must be tight, and all
barriers and covers must be in place.
NOTE: The CAS units are factory charged with the required
amount of oil. If recharging is required, use Emkarate RL
32-3MAF for the CAS units.
COMPRESSOR ROTATION
On 3-phase units with scroll compressors, it is important to
be certain that the compressor is rotating in the proper di-
rection. CAS units are equipped with a Comfort Alert Diag-
nostic Module (CADM). Alert Code 7 indicates reverse pow-
er phasing.
To correct phase order:
1. Turn off power to the unit, tag disconnect.
2. Reverse any two of the unit power leads.
3. Reapply power to the compressor, verify correct
pressures.
To verify the compressor is rotating in the proper direction:
1. Connect service gages to the suction and liquid pres-
sure fittings.
2. Energize the compressor.
3. The suction pressure should drop and the liquid pres-
sure should rise, as is normal on any start-up.
COMPRESSOR OVERLOAD
This overload interrupts power to the compressor when ei-
ther the current or internal motor winding temperature be-
comes excessive, and automatically resets when the inter-
nal temperature drops to a safe level. This overload may
require up to 60 minutes (or longer) to reset. If the internal
overload is suspected of being open, disconnect the elec-
trical power to the unit and check the circuit through the
overload with an ohmmeter or continuity tester.
ADVANCED SCROLL TEMPERATURE PROTECTION
(ASTP)
A label located above the terminal box identifies Cope-
land1Scroll compressor models that contain this
technology. See Fig. 18. Advanced Scroll Temperature
Protection (ASTP) is a form of internal discharge tem-
perature protection, that unloads the scroll compressor
when the internal temperature reaches approximately
149°C (300°F). At this temperature, an internal bi-metal
disk valve opens and causes the scroll elements to sepa-
rate, which stops compression. Suction and discharge
pressures balance while the motor continues to run. The
longer the compressor runs unloaded, the longer it must
cool before the bi-metal disk resets. See Fig. 19.
To manually reset ASTP, the compressor should be stopped
and allowed to cool. If the compressor is not stopped, the
motor will run until the motor protector trips, which occurs up
to 90 minutes later. Advanced Scroll Temperature
Protection will reset automatically before the motor protector
resets, which may take up to 2 hours.
Fig. 18 — Advanced Scroll Temperature Protection
Label
Fig. 19 — Recommended Minimum Cool-Down Time
After Compressor is Stopped
Start Unit
Set the space thermostat to a set point above space tem-
perature so that there is no demand for cooling. Close the
CAS disconnect switch. Only the crankcase heater will be
energized.
Reset the space thermostat below ambient so that a call for
cooling is ensured.
1. Copeland is a trademark of Emerson Climate Technologies.
CAUTION
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage.
Never charge liquid into the low-pressure side of system.
Do not overcharge. During charging or removal of refrig-
erant, be sure indoor-fan system is operating. Ensure
both outdoor fan motors are running; bypass any Motor-
master function.
0
10
20
30
40
50
60
70
80
90
100
110
120
0 10203040 607080 9050
Compressor Unloaded Run Time (Minutes)*
NOTES:
1 . Various factors, including high humidity, high ambient temperature,
and the presence of a sound blanket will increase cool-down times.
*Times are approximate.
Recommended Cooling Time*
(Minutes)

20 Specifications subject to change without notice. CAS-072-153-01SI Rev. A
ADJUST REFRIGERANT CHARGE
Refer to Cooling Charging Charts, Fig. 20-25. Vary refriger-
ant until the conditions of the chart are met. Note that the
charging charts are different from the type normally used.
The charts are based on charging the units to the correct
subcooling for the various operating conditions. Accurate
pressure gage and temperature sensing device are re-
quired. Connect the pressure gage to the service port on
the liquid line service valve. Mount the temperature sensing
device on the liquid line close to the liquid line service valve,
and insulate it so that outdoor ambient temperature does
not affect the reading. Indoor airflow must be within the
unit’s normal operating range. Operate the unit for a mini-
mum of 15 minutes. Ensure that pressure and temperature
readings have stabilized. Plot the liquid pressure and
temperature on chart and add or reduce the charge to meet
the curve. see Table 18. Adjust the charge to conform with
the charging chart, using the liquid pressure and tempera-
ture to read the chart.
FINAL CHECKS
Ensure that all safety controls are operating, control panel
covers are on, and the service panels are in place.
Fig. 20 — CAS072 Charging Chart (RTPF)
Table 18 — Using Plotted Operating Point
IF PLOTTED OPERATING
CONDITION IS ADJUST CHARGE BY
BELOW the curve REDUCE charge
ABOVE the curve ADD charge
Remove Charge if Below
the Curve
Add Charge if Above
the Curve
6 TON DUAL STAGE CHARGING CHART R-410A
(COMPRESSOR FULL LOAD, ALL CONDENSER FANS OPERATING)
60
54
48
42
36
30
24
18
12
6
0
-6
140
120
100
80
60
40
20
50
350
100
700
150
1050
200
1400
250
1750
300
2100
350
2450
400
2800
450
3150
500
3500 3850
550 600
Pressure at Liquid Valve (PSIG / kPa)
Temperature at Liquid Valve (°C/ °F)
PN: 38AU000484 REV -