International comfort products CAS180 User manual

50101340301 10/19
INSTALLATION INSTRUCTIONS
R--410A SPLIT CONDENSING UNITS
CAS180/181--240/241 with RTPF
These instructions must be read and understood completely before attempting installation
Safety Labeling and Signal Words
DANGER, WARNING, CAUTION, and NOTE
The signal words DANGER, WARNING,
CAUTION,andNOTE are used to identify levels of
hazard seriousness. The signal word DANGER is
only used on product labels to signify an immediate
hazard. The signal words WARNING,CAUTION,
and NOTE will be used on product labels and
throughout this manual and other manual that may
apply to the product.
DANGER -- Immediate hazards which will result in
severe personal injury or death.
WARNING --Hazards or unsafe practices which
could result in severe personal injury or death.
CAUTION -- Hazards or unsafe practices which
may result in minor personal injury or product or
property damage.
NOTE -- Used to highlight suggestions which will
result in enhanced installation, reliability, or
operation.
!WARNING
Signal Words in Manuals
The signal word WARNING is used throughout
this manual in the following manner:
The signal word CAUTION is used throughout
this manual in the following manner:
!CAUTION
Signal Words on Product Labeling
Signal words are used in combination with
colors and/or pictures or product labels.
SAFETY CONSIDERATIONS 2..................
MODEL NOMENCLATURE 3....................
INSTALLATION GUIDELINE 4...................
Step 1 -- Plan for Unit Location 9.................
Step 2 -- Complete Pre--Installation Checks 9......
Step 3 -- Prepare Unit Mounting Support 9........
Step 4 -- Rig and Mount Unit 10...................
Step 5 -- Complete Refrigerant Piping 10...........
PRE--START--UP 20.............................
START--UP 20..................................
OPERATING SEQUENCE 28.....................
ROUTINE SYSTEM MAINTENANCE 29...........
SERVICE 29...................................
TROUBLESHOOTING 40........................
APPENDIX A, R--410A Quick Reference Guide 42..
APPENDIX B, Low Ambient Option 43.............
START--UP CHECKLIST 51......................
CHECK VOLTAGE BALANCE 52.................
TABLE OF CONTENTS
!WARNING
PERSONAL INJURY, AND/OR PROPERTY
DAMAGE HAZARD
Failure to carefully read and follow this warning
could result in equipment malfunction, property
damage, personal injury and/or death.
Installation or repairs made by unqualified
persons could result in equipment malfunction,
property damage, personal injury and/or death.
The information contained in this manual is
intended for use by a qualified service technician
familiar with safety procedures and equipped
with proper tools and test instruments.
Installation must conform with local building
codes and with the national Electrical Code
NFPA70 current edition or Canadian Electrical
Code part 1 CSA C.22.1.
Specifications are subject to change without notice.

250101340301
Specifications are subject to change without notice.
SAFETY CONSIDERATIONS
Improper installation, adjustment, alteration, service,
maintenance, or use can cause explosion, fire, electrical
shock, or other conditions which may cause death,
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, protective
clothing, and work gloves. Use quenching cloth for brazing
operations. Have fire extinguisher available. Read these
instructions thoroughly and follow all warnings or cautions
included in literature and attached to the unit. Consult local
building codes, the current editions of the National
Electrical Code (NEC) NFPA 70.
In Canada refer to the current editions of the Canadian
Electrical Code CSA C22.1 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 these
signal words; DANGER,WARNING,andCAUTION. 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.
!WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
Before performing service or maintenance operations on
unit, always turn off main power switch to unit and install
lockout tag. 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 systems operate at higher pressures than R--22
systems. When working with R--410A systems, use only
service equipment and replacement components specifi-
cally rated or approved for R--410A service.
!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 refriger-
ants.
Keep torches and other ignition sources away from refri-
gerants and oils.
!CAUTION
CUT 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
units.
!CAUTION
UNIT DAMAGE HAZARD
Failure to follow this caution may cause equipment dam-
age.
Ensure voltage listed on unit data plate agrees with elec-
trical supply provided for the unit.

3
501 01 3403 01 Specifications are subject to change without notice.
MODEL NOMENCLATURE
MODEL SERIES C A S 1 8 1 H A A 0 A 0 0
Position Number 1 2 3 4 5 6 7 8 9 10 11 12 13
C = R--410A Condensing Unit
A = Air Conditioning (Cooling Only)
H=HeatPump Type
S = Standard ASHRAE 90.1--2010 Efficiency Efficiency
180 = 15 Tons (2 circuit)
181 = 15 Tons (1 circuit)
240 = 20 Tons (2 circuits)
241 = 20 Tons (1 circuit) Nominal Cooling Capacity
H = 208/230--3--60
L= 460--3--60
S= 575--3--50 VOLTAGE
A=SingleCircuit
B = Single Circuit w/ Low Ambient Control
D=DualCircuit
E = Dual Circuit w/ Low Ambient Control Refrigerant System Options
A = Copper / Aluminum Standard
C = E--Coat Copper / Aluminum Outdoor Coil Options
0=None
1 = UnPowered C.O. Service Options
A=None
C = Non--Fused Disconnect Electrical Options
0 = Elec--Mechanical Standard Base Unit Controls
0=FutureUse Future Use

450101340301
Specifications are subject to change without notice.
Installation Guideline
Replacement /Retrofit – R22 to R--410A
Replacement/retrofit installations require change--out of
outdoor 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 may
be re--used, check with the coil manufacturer to verify the coil
construction is suitable for operation with the higher
pressures of R--410A. Also determine if the existing TXV
valve is compatible with R--410A, replace if necessary. The
minimum factory test pressure rating must be 250 psig (1725
kPa). Existing coil will need to be purged with Nitrogen to
remove as much mineral oil as possible to eliminate cross
contamination of oil.
Acid test – If the existing system is being replaced because
of a compressor electrical failure, assume acid is in system.
If system is being replaced for any other reason, use an
approved acid test kit to determine acid level. If even low
levels 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 hours of operation.
Recommendation: Install a ball valve in the liquid line at the
filter drier location when installing a suction filter in the suction
line.
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 tubing
and hot gas bypass tubing if appropriate) and
evaporator if they were not replaced. Removing 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.
4. Remove the existing outdoor unit. Install the new
outdoor 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 hours. 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 is
necessary. Never leave suction--line filter drier in
system longer than 72 hr (actual time).
NOTE: Do not use a torch to remove filter driers, use tubing
cutters. Excess heat from the torch will drive the moisture
contained within the drier back out into the system.

5
501 01 3403 01 Specifications are subject to change without notice.
Figure 1 Unit Dimensions -- 15 Ton
CAS181
CAS180
(FOR CAS180 SYSTEMS)
UNIT
Standard
Weight
Corner
A
Corner
B
Corner
C
Corner
DCenter of Gravity
Unit
Height
lbs. kg. lbs. kg. lbs. kg. lbs. kg. lbs. kg. X Y Z H
CAS181
(RTPF) 731 332 237 107 172 78 135 61 186 84 38 [965.2]
19
[482.6]
17
[431.8]
50 3/8
[1279.2]
CAS180
(RTPF) 731 332 237 107 172 78 135 61 186 84 38 [965.2]
19
[482.6]
17
[431.8]
50 3/8
[1279.2]
LEGEND: RTPF = Round Tube/Plate Fin coil

650101340301
Specifications are subject to change without notice.
Figure 2 Unit Dimensions -- 20 Ton
CAS240
CAS241
(FOR CAS240 SYSTEMS)
UNIT Standard
Weight
Corner
A
Corner
B
Corner
C
Corner
DCenter of Gravity Unit Height
lbs. kg. lbs. kg. lbs. kg. lbs. kg. lbs. kg. X Y Z H
CAS241
(RTPF) 978 444 360 163 188 85 147 67 283 128 38
[965.2]
23
[584.2]
17
[431.8]
50 3/8
[1279.2]
CAS240
(RTPF) 978 444 360 163 188 85 147 67 283 128 38
[965.2]
23
[584.2]
17
[431.8]
50 3/8
[1279.2]
LEGEND: RTPF = Round Tube/Plate Fin coil

7
501 01 3403 01 Specifications are subject to change without notice.
Table 1 Physical Data — 60 Hz English
UNIT CAS 181 180 241 240
NOMINAL CAPACITY (tons) 15 15 20 20
OPERATING WEIGHTS (lb)
Round Tube/Plate Fin Coil (Cu/Al) 731 731 900 900
REFRIGERANT TYPE‡R-410A
Operating Charge, Typical (lb)†24.6 12.0 / 12.0 38.0 19.0 / 19.0
Shipping Charge (lb) 12.2 6.0 / 6.0 28.0 14.0 / 14.0
COMPRESSOR
Qty...Type 2...Scroll 2...Scroll 2...Scroll 2...Scroll
Oil Charge (oz) 60 60 / 60 110 110 / 110
CONDENSER FANS
Qty...Rpm 3...1100 3...1100 4...1100 4...1100
Motor Hp 1/41/4 1/41/4
Diameter 22 22 22 22
Nominal Airflow (Cfm Total) 9,000 9,000 12,000 12,000
Watts (Total) 970 970 1150 1150
RTPF CONDENSER COIL
Material (Tube/Fin) Cu / Al Cu / Al Cu / Al Cu / Al
Coil Type 3/8-- i n R T P F 3/8-- i n R T P F 3/8-- i n R T P F 3/8-- i n R T P F
Rows/Fins per inch (FPI) 2/17 2/17 2/17 2/17
Face Area (sq ft total) 47.0 47 50.0 50
CONTROLS
Pressurestat Settings (psig)
High Cutout 630 10
Cut-in 505 20
Low Cutout 54 3
Cut-in 117 5
PIPING CONNECTIONS (in. ODS)
Qty...Suction 1...13/82...13/81...15/82...13/8
Qty...Liquid 1...5/82...1/21...5/82...1/2
LEGEND
RTPF — Round Tube/Plate Fin Coil
ODS — Outside Diameter Sweat (socket)
* Unit is factory--supplied with partial charge only.
† Typical operating charge with 25 ft of interconnecting piping.
** Storage capacity of condenser coil with coil 80% full of liquid
R--410A at 95_F.

850101340301
Specifications are subject to change without notice.
Table 2 Physical Data — 60 Hz SI
UNIT CAS 181 180 241 240
NOMINAL CAPACITY (kW) 52.7 52.7 70.3 70.3
OPERATING WEIGHT (kg)
Round Tube/Plate Fin Coil (Cu/Al) 332 332 409 409
REFRIGERANT TYPE‡R-410A
Operating Charge, Typical (kg)†11.1 5.4 / 5.4 17.2 8.6 / 8.6
Shipping Charge (kg) 5.4 2.7 / 2.7 12.7 6.8 / 6.8
COMPRESSOR Scroll
Qty...Type 2...Scroll 2...Scroll 2...Scroll 2...Scroll
Oil Charge (L) 1.7 1.7 / 1.7 3.2 3.2 / 3.2
CONDENSER FANS
Qty...r/s 3...18 3...18 4...18 4...18
Motor Hp NEMA 1/41/41/41/4
Diameter (mm) 560 560 560 560
Nominal Airflow (L/s) 4248 4248 5663 5663
Watts (Total) 970 970 1150 1150
RTPF CONDENSER COIL (Qty)
Material (Tube/Fin) Cu / Al Cu / Al Cu / Al Cu / Al
Coil Type 3/8-- i n R T P F 3/8-- i n R T P F 3/8-- i n R T P F 3/8-- i n R T P F
Rows/Fins per Meter (Fins/m) 1...670 1...670 2...670 2...670
Face Area (sq m total) 4.4 4.4 4.6 4.6
CONTROLS
Pressurestat Settings (kPa)
High Cutout 4347 70
Cut-in 3482 138
Low Cutout 372 21
Cut-in 807 34
PIPING CONNECTIONS (mm ODS)
Qty...Suction 1...34.9 2...34.9 1...38.7 2...34.9
Qty...Liquid 1...13.3 2...12.7 1...13.3 2...12.7
LEGEND
RTPF — Round Tube/Plate Fin
NEMA — National Electrical Manufacturers Association
ODS — Outside Diameter Sweat (socket)
‡Unit is factory-supplied with partial charge only.
†Typical operating charge with 7.62 m of interconnecting piping.

9
501 01 3403 01 Specifications are subject to change without notice.
Matching CAS Model To Evaporator Coil
The Model CAS181/241 is a single-circuit unit design,
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).
The Model CAS180/240 is a dual-circuit unit design that
requires 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 CAS180/240 CANNOT be connected to a
single-circuit evaporator coil. The Model CAS180/240
CANNOT be field-converted to a single-circuit design.
Table 3 – Evaporator Coil Connections
Evaporator
Coil Connect to Model Notes
Single Circuit CAS181/241
ONLY
Two Circuits
CAS181/241 Manifold evaporator circuits
into single piping system
Or
CAS180/240 Use two separate piping
systems
Before unpacking this new CAS model, compare the
evaporator coil design to the CAS model.
Jobsite Survey
Complete the following checks before installation.
1. Consult local building codes and the NEC (National
Electrical 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
Select a location for the unit and its support system (pad, rails
or other) that provides for the minimum clearances required
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 Figure 3.
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
recirculation from the condenser fan discharge is possible.
Do not locate the unit in a well or next to high walls.
Evaluate the path and required line length for interconnecting
refrigeration piping, including suction riser requirements
(outdoor unit above indoor unit), liquid line lift (outdoor unit
below indoor unit) and hot gas bypass line. Relocate sections
to minimize the length of interconnecting tubing.
!CAUTION
UNIT OPERATION HAZARD
Failure to follow this caution may result in improper
operation.
Do not bury refrigerant piping underground.
Although unit is weatherproof, avoid locations that permit
water from higher level runoff and overhangs to fall onto the
unit.
Figure 3 Service Clearance Dimensional Drawing
LEFT:
Min 18” (457 mm)
requried for service
RIGHT:
Min 18” (457 mm)
requried for service
REAR:
Min 18” (457 mm)
requried for service
Note: Observe requirements for 39” (914 mm) operating clearance
on either Left or Rear coil opening.
FRONT:
42” (1067 mm)
Step 2 — Complete Pre--Installation Checks
CHECK UNIT ELECTRICAL CHARACTERISTIC — Confirm
before installation of unit that voltage, amperage and circuit
protection requirements listed on unit data plate agree with
power supply provided.
UNCRATE 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 damaged or incomplete.
CONSIDER SYSTEM REQUIREMENTS
SConsult local building codes and National Electrical
Code (NEC, U.S.A.) for special installation
requirements.
SAllow sufficient space for airflow clearance, wiring,
refrigerant piping, and servicing unit. See Figure 1 and
2 for unit dimensions and weight distribution data.
SLocate the unit so that the outdoor coil (condenser)
airflow is unrestricted on all sides and above.
SThe unit may be mounted on a level pad directly on the
base channels or mounted on raised pads at support
points. See Tables 1 and 2 for unit operating weights.
See Figure 1 and 2 for weight distribution based on
recommended support points.
NOTE: If vibration isolators are required for a particular
installation, use the data in Figure 1 and 2 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

10 50101340301
Specifications are subject to change without notice.
of condenser coil air inlet to prevent grass and foliage from
obstructing airflow.
Step 4 -- Rig and Mount the Unit
!CAUTION
UNIT OPERATION 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.
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
forcetotheunit.
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 5 — Complete Refrigerant Piping
Connections
!CAUTION
UNIT OPERATION HAZARD
Failure to follow this caution may result in improper
operation.
Do not bury refrigerant piping underground.
!CAUTION
UNIT OPERATION HAZARD
Failure to follow this caution may result in improper
operation.
A refrigerant receiver is not provided with the unit. Do not
install a receiver.
PROVIDE SAFETY RELIEF — If local codes dictate an
additional safety relief device, purchase 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 CAS180/240 has two separate refrigeration systems. If
required, each circuit will require a field-supplied/installed
supplemental relief device.
Table4–EquivalentLengthsforCommonFittings(ft)
Nominal
Tube
OD
Elbows
90Std 90Lrad 90Street 45Std 45Street
3/81.3 0.8 2.2 0.6 1
1/21.4 0.9 2.3 0.7 1.1
5/81.6 12.5 0.8 1.3
3/41.8 1.2 2.9 0.9 1.5
7/821.4 3.2 0.9 1.6
11/82.6 1.7 4.1 1.3 2.1
13/83.3 2.3 5.6 1.7 3
15/842.6 6.3 2.1 3.4
21/853.3 8.2 2.6 4.5
Nominal
Tube
OD
Tees
Branch
Flow
Straight-Thru
No Reduct Reduce 25% Reduce 50%
3/82.6 0.8 1.1 1.3
1/22.7 0.9 1.2 1.4
5/83 1 1.4 1.6
3/43.5 1.2 1.7 1.8
7/841.4 1.9 2
11/851.7 2.3 2.6
13/872.3 3.1 3.3
15/882.6 3.7 4
21/810 3.3 4.7 5
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.
SIZE REFRIGERANT LINES — Select the recommended
line sizes for CAS181/241 and CAS180/240 unit from the
appropriate tables.
Determine the linear length of interconnecting piping
required between the outdoor unit and indoor unit
(evaporator). Consider and identify also the arrangement of
the tubing path (quantity and type of elbows in both lines),
liquid line solenoid size, filter drier and any other
refrigeration specialties located in the liquid line. Refer to
the indoor unit installation 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 4,
Equivalent Lengths for Common Fittings, for usual fitting
types. Also identify adjustments for refrigeration specialties.
NOTE: Equivalent line lengths will vary based on tube
diameter. Calculate equivalent line length for each pipe by
adding equivalent length adjustments to linear lengths for
each pipe.
Enter the appropriate table to select the recommended line
sizes.

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501 01 3403 01 Specifications are subject to change without notice.
Model: Line Sizes Table Quantity of Line
Sets
CAS181/241 5 1
CAS180/240 6 2
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 subcooling at the
evaporator 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 5 (CAS181/241) and 6 (CAS180/240) for
maximum liquid lift capabilities for line sizes. Reselect the
liquid line tube size if necessary. If maximum available tube
size cannot provide the required lift distance on this
installation, relocate the outdoor unit to reduce the
equivalent line length or the lift requirement.
Suction Riser —
A suction riser condition exists when the outdoor unit is
located 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 produce the minimum refrigerant velocity to ensure
oil return at minimum load conditions.
Check Table 7 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 recommended suction tube
size does not provide necessary minimum flowrates for this
riser.
Table 5 – CAS181/241 Piping Recommendations (Single-Circuit Unit)
R-410A Equivalent Length
Ft 0-38 38-75 75-113 113-150 150-188
m0-12 12-23 23-34 34-46 46-57
Model Typ Linear ft 0-25 25-50 50-75 75-100 100-125
CAS181
Liquid Line 5/85/85/85/85/8
Max Lift 25 50 75 100 125
Suction Line 1-1/81-3/81-3/81-3/81-3/81-5/8
Charge (lbs) 24.3 27.5 30.6 33.7 37.8
CAS241
Liquid Line 5/85/85/85/85/8
Max Lift 25 50 71 77 63
Suction Line 1-1/81-3/81-3/81-3/81-5/81-5/81-5/8
Charge (lbs) 37.8 40.8 44.6 47.8 51.1
Legend:
Length Equiv Equivalent tubing length, including effects of refrigeration specialties devices
Typ Linear Typical linear tubing length, Feet (50% added to linear to define Equivalent Length for this table)
Liquid Line Tubing size, inches OD.
Max Lift Maximum liquid lift (indoor unit ABOVE outdoor unit only), at maximum permitted liquid line pressure drop —
SLinear Length Less than 100 ft: Minimum 2.0F subcooling entering TXV
SLinear Length Greater than 100 ft: Minimum 0.5F subcooling entering TXV
Suction Line Tube size, inches OD
Charge Charge Quantity, lbs. Calculated for both liquid line sizes (where applicable), but only with larger suction line size
(where applicable)
NOTE: For applications with equivalent length greater than 188 ft (57 m) and/0r linear length greater than 125 ft (38 m),
contact your local distributor.

12 50101340301
Specifications are subject to change without notice.
Table 6 – CAS180/240 Piping Recommendations (Two-Circuit Unit)
NOTE: CAS180/240 requires TWO sets of refrigeration piping
R-410A Equivalent Length
Ft 0-38 38-75 75-113 113-150 150-188
m0-12 12-23 23-34 34-46 46-57
Model Typ Linear ft 0-25 25-50 50-75 75-100 100-125
CAS180
Liquid Line 1/21/21/21/21/2
Max Lift 25 50 75 100 125
Suction Line 7/811/811/811/811/8
Charge ea. (lbs) 11.7 13.8 15.7 17.6 19.6
CAS240
Liquid Line 1/21/21/25/81/25/81/25/8
Max Lift 25 50 54 75 60 99 46 95
Suction Line 11/811/811/811/813/813/8
Charge (lbs) A
B
19.3
18.3
21.0
20.3
23.0
22.0
26.0
25.0
25.9
24.9
29.7
28.7
28.0
27.0
32.7
31.7
Legend:
Length Equiv Equivalent tubing length, including effects of refrigeration specialties devices
Typ Linear Typical linear tubing length, Feet (50% added to linear to define Equivalent Length for this table)
Liquid Line Tubing size, inches OD.
Max Lift Maximum liquid lift (indoor unit ABOVE outdoor unit only), at maximum permitted liquid line pressure drop —
SLinear Length Less than 100 ft: Minimum 2.0F subcooling entering TXV
SLinear Length Greater than 100 ft: Minimum 0.5F subcooling entering TXV
Suction Line Tube size, inches OD
Charge Charge Quantity, lbs. Calculated for both liquid line sizes (where applicable), but only with larger suction line size
(where applicable)
NOTE: For applications with equivalent length greater than 188 ft (57 m) and/0r linear length greater than 125 ft (38 m),
contact your local distributor.
Table7–CAS Maximum Suction Pipe Size
Model: Maximum Tube Size
CAS181/241
15/8
15/8
CAS180/240
15/8
15/8
Insulate Suction Lines —
Apply closed-cell tubular insulation to all suction lines
between evaporator coil connection and CAS unit’s suction
service valve.
Hot Gas Bypass —
Hot gas bypass, if used, should be introduced before the
evaporator. (A bypass route that also bypasses the
evaporator circuit may lead to oil trapping in the evaporator
circuit during low load conditions and then to oil slugging as
evaporator load increases.) Model CAS units do not
include a hot gas stub connection; a tee must be
field-supplied and installed in the compressor discharge
line. Run a 1/2-in OD line between outdoor unit and
evaporator coil inlet. Install an Auxiliary Side Connector at
the evaporator between TXV and distributor (follow
instructions for the side connector part). Insulate the hot
gas line.
CAS180/240: Generally only one hot gas bypass system
will be applied on a two-circuit unit. Connect the hot gas
bypass system to Circuit 1 (first-on/last-off, connected to
the evaporator coil’s bottom circuit).
CAS180/240 Piping Connections —
The CAS180/240’s two circuits are designated Circuit 1
and Circuit 2. Circuit 1 is controlled by the thermostat’s Y1
(or TC1) 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. 4 for location of Circuit 1 and Circuit 2 service
valves and field piping connections. Circuit 1 is on the
left-hand side of the service valve compartment; Circuit 2 is
on the right.
When a single piece evaporator coil with two separate
circuits is connected to a CAS180/240, the lower coil circuit
should be connected to the CAS180/240’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).

13
501 01 3403 01 Specifications are subject to change without notice.
Circuit 1
Connections
Circuit 2
Connections
CKT
1
CKT
1
CKT
2
CKT
2
Figure 4 CAS180/240 Service valve Locations
Plan the Circuit 1 and Circuit 2 tubing segments carefully,
mark each segment and check constantly as piping
systems are assembled to avoid piping errors.
CAS180/240 unit cannot be field-piped as a
single-circuit/tandem system.
Connecting FAS to CAS180/240: TheFASfancoilin
sizes 15, 20 and 25 ton is a face-split coil design that also
has its circuits designated as 1 and 2. See Fig.5. Note that
the lower coil segment changes as the arrangement of the
FAS changes. In a vertical arrangement, the FAS’s lower
coil segment is segment 2; this segment should be
connected to the CAS180/240’s Circuit 1. In a horizontal
arrangement, the FAS’s lower segment is now segment 1;
this segment should be connected to the CAS180/240’s
Circuit 1.
Note that refrigerant suction piping should be insulated.
FAS
Arrangement
Cooling
Stage
FAS Coil
Segment
Connect to
CAS180/240
Vertical Y1
Y2
2
1
Circuit 1
Circuit 2
Horizontal Y1
Y2
1
2
Circuit 1
Circuit 2
Install Filter Drier(s) and Moisture Indicator(s) —
Every unit MUST have a filter drier in the liquid line.
CAS180/240 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.
CAS units include one (CAS181/241) or two (CAS180/240)
R--410A-duty filter drier(s), shipped in cartons attached to
the unit basepan. Remove the filter 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.
Figure 5 Typical Evaporator Coil Connections (FAS)
FIRST ON/LAST OFF = 2
VERTICALINSTALLATION
FIRST O N/LA ST OF F = 1
HORIZONTAL INSTALLATION
1
2
2
1
Table8–R--410A-dutyFilterDrier(s)
Model-Size Qty
Liquid
Line OD
Desiccant
Volume
Part
Number Ref
CAS181 15/8-in 30 cu. in. KH43LS087
CAS241 15/8-in 30 cu. in. KH43LS087
CAS180 21/2-in 16 cu. in. KH43LS085
CAS240 21/2-in 16 cu. in. KH43LS085
Installation of liquid line moisture indicating sightglass in
each circuit is recommended. Locate the sightglass(es)
between the outlet of the filter drier and the TXV inlet.
Refer to Table 9 for recommendations on refrigeration
specialties.
Table 9 – Refrigerant Specialties Part Numbers.
LIQUID LINE
SIZE (in.)
LIQUID LINE
SOLENOID VALVE (LLSV)
LLSV
COIL
SIGHT
GLASS
FILTER
DRIER
1/21179872 1179874 1179877 provided with unit
see Table 8
5/81179873 1179874 1179878
CAS180/240 units require TWO sets of parts.

14 50101340301
Specifications are subject to change without notice.
Figure 6 Location of Sight Glass(es) and Filter Driers
Typical CAS181/241 Systems
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
Figure 7 Location of Sight Glass(es) and Filter Driers
Typical CAS180/240 Systems
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
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. 6) or 2 filter driers and sight glasses
may be installed at B locations (see Figs. 6 and 7).
Select the filter drier for maximum unit capacity and
minimum 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 Figs. 6 & 7) between the condensing
unit and the evaporator coil. Locate the solenoid valve at
the outlet end of the liquid line, near the evaporator coil
connections, with flow direction arrow pointed at the
evaporator coil. Refer to Table 9. (A liquid line solenoid
valveisrequiredwhentheliquidlinelengthexceeds75ft
[23 m].) This valve prevents refrigerant migration (which
causes oil dilution) to the compressor during the off cycle,
at low outdoor ambient temperatures. Wire the solenoid in
parallel with the compressor contactor coil (see Figs. 6 &
7). This means of electrical control is referred to as
solenoid drop control.
Capacity Control Liquid Line Solenoid Valve: Evaporator
capacity control via liquid solenoid valve is not recommended
for use with CAS models.
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.
Figure 8 Typical Piping Connection Assembly
Factory
High-Flow
A
ccess Port
Service Valve
with Stem Cap
Field Service
Access Port
(Schrader core)
Sweat
Connection
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 2-3 in-lbs
(23-34 N-cm).

15
501 01 3403 01 Specifications are subject to change without notice.
Evacuation/Dehydration —
Evacuate and dehydrate the connected refrigeration
system(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.
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
pressure than standard R--22 systems. Do not use
R--22 service equipment or components on R--410A
refrigerant equipment.
!WARNING
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
cylinders. These cylinders areavailablewithandwithout
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 removing 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
recommended 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
intothehighsideofeachCAScircuitthroughtheliquid
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
factory 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, Recover, Recycling, and Reclamation for
liquid charging procedures.
Example:
CAS240
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 6 (CAS180/240):
Liquid 1/2in
Suction 1-1/8in.
Charge
Circuit 1: 23.0 lbs (at 75-ft linear length)
Circuit 2: 22.0 lbs
80% of Operating Charge:
Circuit 1: 0.80 x 23.0 = 18.4 lbs
Circuit 2: 0.80 x 22.0 = 17.6 lbs
Factory Shipping Charge: 15 lbs
Field-Charge
Circuit 1: 18.4 -- 15 = 3.4 lbs
Circuit 2: 17.6 -- 15 = 2.6 lbs
For linear line lengths longer than 125 ft (38 m), contact
your local distributor for system charge value.
Step 1 — 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
instructions shipped with the accessory.
Step 2 — Complete Electrical Connections
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal
injury or death.
Do not use gas piping as an electrical ground. 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 (National
Electrical Code); ANSI/NFPA 70, latest edition (in
Canada, Canadian Electrical Code CSA [Canadian
Standards Association] C22.1), and local electrical codes.
!WAR N ING
NOTE: Check all factory and field electrical connections
for tightness. Field-supplied wiring shall conform with the
limitations 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 convenience outlet. If an always-energized
convenience outlet operation 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

16 50101340301
Specifications are subject to change without notice.
disconnect switch operation of the convenience 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 compressor
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
wiring 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
contactor C or optional disconnect switch. These leads are
for factory run-test purposes only; remove and discard
before connecting field power wires to unit connection
points. Make field power connections directly to line
connection pressure lugs only.
FIRE HAZARD
Failure to follow this warning could cause in personal
injury, death and/or equipment damage.
Do not connect aluminum wire between disconnect
switch and condensing unit. Use only copper wire.
(See Fig. 9.)
!WARNING
Figure 9 Disconnect Switch and Unit
COPPER
WIRE ONLY
ELECTRIC
DISCONNECT
SWITCH
ALUMINUM
WIRE
Units Without Factory-Installed Disconnect —
When installing units, provide a disconnect switch per NEC
(National Electrical Code) of adequate size. Disconnect
sizing 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.
Units with Factory-Installed 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.
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. 10 for power wiring
connections to the unit contactor and terminal block and
equipment ground.
Provide a ground-fault and short-circuit over-current
protection device (fuse or breaker) per NEC Article 440 (or
local codes). Refer to unit informative data plate for MOCP
(Maximum 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
transformer must be rewired by moving the black wire with
the



-in. female spade connector from the 230-v
connection and moving it to the 208-v



-in. male terminal
on the primary side of the transformer. Refer to unit label
diagram for line-side information.
Figure 10 Power Wiring Connections
11 13
L1 L2 L3
CTB1
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
Affix the crankcase heater warning sticker to the unit
disconnect switch.
Convenience Outlets —
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. Tag-out
this switch, if necessary.
!WAR N ING
A non--powered convenience outlets is offered on CAS
models and provide a 125-volt GFCI (ground-fault
circuit-interrupter) duplex receptacle rated at 15-A behind a
hinged waterproof access cover, located on the end panel
oftheunit.SeeFig.11.
Non-powered type: This type requires the field installation
of a general-purpose 125-volt 15-A circuit powered from a

17
501 01 3403 01 Specifications are subject to change without notice.
source elsewhere 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 power supply conductors into the bottom of
the utility box containing the duplex receptacle.
Figure 11 Convenience Outlet Location
Convenience
Outlet
GFCI
Control Box
Access Panel
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal
injury or death.
Using unit-mounted convenience outlets: Units with
unit-mounded 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.
!WARNING
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
approximately 1/2--in (13 mm) under screw heads are
exposed. 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. 12. 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.
Figure 12 Weatherproof Cover Installation
All Units —
Voltage to compressor terminals during operation must be
within voltage range indicated on unit nameplate. See
Table 10. On 3-phase units, voltages between phases must
be balanced within 2% and the current within 10%. Use the
formula shown in the legend for Tables 10 and 11, Note 5
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 warranty.
Field Control Wiring —
CAS unit control voltage is 24v. See Fig. 13 (CAS181/241)
and Fig. 14 (CAS180/240) for typical field control
connections 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
according to the specific construction details of the indoor
section (air handler or packaged fan coil). Fig. 13
(CAS181/241) and Fig. 14 (CAS180/240) depict typical
connections to a FAS fan coil unit. Plan for field
connections carefully and install control wiring correctly per
the project plan. Additional components and supplemental
transformer accessory may be required.
The CAS unit requires an external temperature control
device. This device can be a thermostat (field-supplied) or
a thermostat emulation device provided as part of a
third--party Building Management System.
Thermostat —
Install an approved accessory thermostat according to
installation instructions included with the accessory. Locate
the thermostat accessory on a solid wall in the conditioned
space to sense average temperature in accordance with
the thermostat installation instructions.

18 50101340301
Specifications are subject to change without notice.
The CAS181/241 is a single-circuit, two--stage cooling unit.
Select a two—stage cooling thermostat, with or without
supplemental heating as needed.
The CAS180/240 is a dual--circuit, two-stage cooling unit.
Select a two—stage cooling thermostat, with or without
supplemental heating as needed.
Select a thermostat cable or equivalent single leads of
different colors with minimum of five leads for CAS181/241 or
six leads for CAS180/240 unit. Check the thermostat
installation instructions for additional features which might
require additional conductors in the cable.
Forwirerunsupto50ft.(15m),useno.18AWG
(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 minimum). For over 75 ft. (23 m), use no. 14 AWG
insulated wire (35C minimum). All wire sizes larger than
no. 18 AWG cannot be directly connected to the thermostat
and will require a junction box and splice at the thermostat.
Figure 13 Typical Remote Thermostat Connections
CAS181/241
Note 1: Typical multi-function marking. Follow manufacturer’s configuration
instructions to select Y2.
Note 2: Connect only if thermostat requires 24-vac power source.
Note 3: Connect W1 and W2 if supplemental heaters are installed
Field Wiring
(Note 1)
(Note 2)
(Note 3)
(Note 3)
Figure 14 Typical Remote Thermostat Connections
CAS180/240
Note 1: Typical multi-function marking. Follow manufacturer’s configuration
instructions to select Y2.
Note 2: Connect only if thermostat requires 24-vac power source.
Note 3: Connect W1 and W2 if supplemental heaters are installed
Field Wiring
(Note 1)
(Note 2)
(Note 3)
(Note 3)
Control Circuit Wiring —
Control voltage is 24 v. See Figs. 13 and 14 and the unit’s
label diagram for field--supplied wiring details. Route
control wires through the opening in unit’s end panel to the
connection in the unit’s control box.
Control Transformer Wiring —
On multi voltage units, check the transformer primary
wiring connections. See Fig. 15 or refer to the unit’s label
diagram.
If the unit will be operating at 208-3-60 power, remove the
black wire (BLK) from the transformer primary connection
labelled “230” and move it to the connection labelled “208”.
See Fig. 15.
Figure 15 Control Transformer Wiring

19
501 01 3403 01 Specifications are subject to change without notice.
Table 10 – Unit Wire/Fuse or HACR Breaker Sizing Data
UNIT
SIZE
CAS
NOMINAL
POWER
SUPPLY
VOLTAGE
RANGE
COMPRESSOR NO C.O. or UNPWRD C.O.
No. 1 No. 2 OFM POWER SUPPLY DISCONNECT SIZE
V--Ph--Hz Min Max RLA LRA RLA LRA Qty
FLA
(ea) MCA
FUSE or
HACR
BRKR FLA LRA
181
180
208/230--3--60 187 253 25.0 164 25.0 164 31.5 60.8/60.8 80/80 63/63 337/337
460--3--60 414 506 12.2 100 12.2 100 30.8 29.9 40 31 206
575--3--60 518 633 9.0 78 9.0 78 30.7 22.4 30 23 162
241
240
208/230--3--60 187 253 30.1 225 30.1 225 41.5 73.7/73.7 100/100 76/76 462/462
460--3--60 414 506 16.7 114 16.7 114 40.8 40.8 50 42 236
575--3--60 518 633 12.2 80 12.2 80 40.7 30.3 40 31 168
Legend and Notes for Table 10
LEGEND:
BRKR --- Circuit breaker
CO --- Convenient outlet
FLA --- Full Load Amps
LRA --- Locked Rotor Amps
MCA --- Minimum Circuit Amps
Protection
NEC --- National Electrical Code
RLA --- Rated Load Amps
UNPWR CO --- Unpowered convenient outlet
NOTES:
1. In compliance with NEC requirements for multimotor and
combination load equipment (refer to NEC Articles 430 and
440), the overcurrent protective device for the unit shall be
fuse or HACR breaker. Canadian units may be fuse or cir-
cuit breaker.
2. The MCA values are calculated in accordance with The
NEC. Article 440.
3. Motor RLA and LRA values are established in accordance
with Underwriters’ Laboratories (UL). Standard 1995.
4. The 575---v units are UL, Canada---listed only.
5. 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 de-
termine the percentage of voltage imbalance.
Example: Supply voltage is 230-3-60
%VoltageImbalance =100x
max voltage deviation from average voltage
average voltage
AB = 224 v
BC=231v
AC = 226 v
Average Voltage =
(224+231+226)
=
681
33
=227
Determine maximum deviation from average voltage.
(AB) 227 – 224 = 3 v
(BC)231–227=4v
(AC)227–226=1v
Maximum deviation is 4 v.
Determine percent of voltage imbalance.
%VoltageImbalance =100 x
4
227
=1.76%
This amount of phase imbalance is satisfactory as it is below the
maximum allowable 2%.
IMPORTANT: If the supply voltage phase imbalance is more than 2%,
contact your local electric utility company immediately.

20 50101340301
Specifications are subject to change without notice.
PRE-START-UP
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.
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage.
Do not attempt to start the condensing unit, even
momentarily, until the following steps have been
completed. Compressor damage may result.
CAUTION
!
System Check
1.The electrical power source must agree with the unit’s
nameplate rating.
2.Check all air handler(s) and other equipment auxiliary
components. Consult the manufacturer’s instructions
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 “Preliminary
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
energize 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
operating charge listed in the Physical Data table (Tables 1
through 2. Allow high and low side pressures to equalize
before starting compressor. If pressures 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.
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.
CAUTION
!
START-UP
CAS Units: T:he 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 preliminary 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.Re--check 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.
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 in 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
direction. CAS units are equipped with a Comfort Alert
Diagnostic Module (CADM). Alert Code 7 indicates reverse
power 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 pressure
fittings.
2.Energize the compressor.
3.The suction pressure should drop and the liquid pressure
should rise, as is normal on any start--up.