These publications can help you install the air
conditioner or heat pump. You can usually find these at
your local library or purchase them directly from the
publisher. Be sure to consult current edition of each
standard.
National Electrical Code ....................... ANSI/NFPA 70
Standard for the Installation ............... ANSI/NFPA 90A
of Air Conditioning and Ventilating Systems
Standard for Warm Air ........................ ANSI/NFPA 90B
Heating and Air Conditioning Systems
Load Calculation for ............................. ACCA Manual J
Residential Winter and Summer Air Conditioning
Duct Design for Residential ................ACCA Manual D
Winter and Summer Air Conditioning and Equipment
Selection
FOR MORE INFORMATION, CONTACT
THESE PUBLISHERS:
ACCAAir Conditioning Contractors of America
1712 New Hampshire Avenue NW
Washington, DC 20009
Telephone: (202) 483-9370
Fax: (202) 234-4721
ANSIAmerican National Standards Institute
11 West Street, 13th Floor
New York, NY 10036
Telephone: (212) 642-4900
Fax: (212) 302-1286
X - Barometric Fresh Air Damper (Standard)
B - Blank-off Plate
M - Motorized Fresh Air Damper
V - Commercial Room Ventilator - Motorized with Exhaust
E - Economizer (Internal - Fully Modulating with Exhaust
R - Energy Recovery Ventilator - with Exhaust
NOTE: For 0KW and circuit breakers (230/208 Volt) or pull disconnects (460 Volt) applications, insert 0Z in the KW field of model no.
REVISIONS
VOLTS & PHASE
A - 230/208/60/1
B - 230/208/60/3
C - 460/60/3
TABLE 1 – ELECTRICAL SPECIFICATIONS
KW
FILTER OPTIONS
X - 1-Inch Throwaway
(Standard)
W - 1-Inch Washable
P - 2-Inch Pleated
COLOR OPTIONS
X - Beige (Standard)
1 - White
2 - Mesa Brown
4 - Buckeye Gray
5 - Desert Brown
6 - Dark Bronze
X - Front (Standard)
T - Top on WA30 & WA37 Models
3
detaR
/stloV
sledoM
Z0A-203AW
50A
01A
51A
Z0B-203AW
90B
51B
Z0C-203AW
90C
51C
Z0A-273AW
50A
80A
01A
51A
Z0B-273AW
60B
90B
51B
Z0C-273AW
60C
90C
21C
51C
1 Maximum size of the time delay fuse or HACR type circuit breaker for protection of field wiring conductors.
2 Based on 75° copper wire. All wiring must conform to the National Electrical Code and all local codes.
3 These "Minimum Circuit Ampacity" values are to be used for sizing the field power conductors. Refer to the National Electric Code
(latest revision), Article 310 for power conductor sizing.
CAUTION: When more than one field power conductor circuit is run through one conduit, the conductors must be derated. Pay special
attention to note 8 of table 310 regarding Ampacity Adjustment Factors when more than three conductors are in a raceway.
Upon receipt of equipment, the carton should be
checked for external signs of shipping damage. If
damage is found, the receiving party must contact the
last carrier immediately, preferably in writing,
requesting inspection by the carrier’s agent.
GENERAL
The equipment covered in this manual is to be installed
by trained, experienced service and installation
technicians.
The refrigerant system is completely assembled and
charged. All internal wiring is complete.
The unit is designed for use with or without duct work.
Flanges are provided for attaching the supply and return
ducts.
These instructions explain the recommended method to
install the air cooled self-contained unit and the
electrical wiring connections to the unit.
B-203AW
B-273AW
C-203AW
C-273AW
These instructions and any instructions packaged with
any separate equipment required to make up the entire
air conditioning system should be carefully read before
beginning the installation. Note particularly “Starting
Procedure” and any tags and/or labels attached to the
equipment.
While these instructions are intended as a general
recommended guide, they do not supersede any national
and/or local codes in any way. Authorities having
jurisdiction should be consulted before the installation is
made. See Page 3 for information on codes and
standards.
Size of unit for a proposed installation should be based
on heat loss calculation made according to methods of
Air Conditioning Contractors of America (ACCA). The
air duct should be installed in accordance with the
Standards of the National Fire Protection Association for
the Installation of Air Conditioning and Ventilating
Systems of Other Than Residence Type, NFPA No. 90A,
and Residence Type Warm Air Heating and Air
Conditioning Systems, NFPA No. 90B. Where local
regulations are at a variance with instructions, installer
should adhere to local codes.
Manual 2100-404E
Page6 of 19
DUCT WORK
All duct work, supply and return, must be properly sized
for the design airflow requirement of the equipment. Air
Conditioning Contractors of America (ACCA) is an
excellent guide to proper sizing. All duct work or
portions thereof not in the conditioned space should be
properly insulated in order to both conserve energy and
prevent condensation or moisture damage.
Refer to Table 11 for maximum static pressure available
for duct design.
Design the duct work according to methods given by the
Air Conditioning Contractors of America (ACCA).
When duct runs through unheated spaces, it should be
insulated with a minimum of 1-inch of insulation. Use
insulation with a vapor barrier on the outside of the
insulation. Flexible joints should be used to connect the
duct work to the equipment in order to keep the noise
transmission to a minimum.
A 1/4 inch clearance to combustible material for the first
3 feet of duct attached to the outlet air frame is required.
See Wall Mounting Instructions and Figures 3 and 4 for
further details.
Ducts through the walls must be insulated and all joints
taped or sealed to prevent air or moisture entering the
wall cavity.
FRESH AIR INTAKE
All units are built with fresh air inlet slots punched in
the service panel.
If the unit is equipped with the fresh air damper
assembly, the assembly is shipped already attached to
the unit. The damper blade is locked in the closed
position. To allow the damper to operate, the maximum
and minimum blade position stops must be installed.
See Figure 2.
All capacity, efficiency and cost of operation
information as required for Department of Energy
“Energyguide” Fact Sheets is based upon the fresh air
blank-off plate in place and is recommended for
maximum energy efficiency.
The blank-off plate is available upon request from the
factory and is installed in place of the fresh air damper
shipped with each unit.
CONDENSATE DRAIN
A plastic drain hose extends from the drain pan at the
top of the unit down to the unit base. There are
openings in the unit base for the drain hose to pass
through. In the event the drain hose is connected to a
drain system of some type, it must be an open or vented
type system to assure proper drainage.
CAUTION
Some installations may not require any return
air duct. A metallic return air grille is required
with installations not requiring a return air
duct. The spacing between louvers on the
grille shall not be larger than 5/8 inches.
Any grille that meets the 5/8 inch louver criteria may be
used. It is recommended that Bard Return Air Grille Kit
RG-2 through RG-5 or RFG-2 through RFG-5 be
installed when no return duct is used. Contact
distributor or factory for ordering information. If using
a return air filter grille, filters must be of sufficient size
to allow a maximum velocity of 400 fpm.
FILTERS
A 1-inch throw away filter is suppled with each unit.
The filter slides into position making it easy to service.
This filter can be serviced from the outside by removing
the service door. A 1-inch washable filter and a 2-inch
pleated filter are also available as optional accessories.
The internal filter brackets are adjustable to
accommodate the 2-inch filter by bending the metal tabs
holding the 1-inch filter down. There are two tabs on
each side of the filter.
FIGURE 2
FRESH AIR DAMPER ASSEMBLY
Manual2100-404E
Page7 of 19
INSTALLATION INSTRUCTIONS
WALL MOUNTING INFORMATION
1. Two holes, for the supply and return air openings,
must be cut through the wall as shown in Figure 3.
2. On wood-frame walls, the wall construction must be
strong and rigid enough to carry the weight of the unit
without transmitting any unit vibration.
WARNING
Fire hazard can result if 1/4 inch clearance to
combustible materials for supply air duct is not
maintained. See Figure 3.
3. Concrete block walls must be thoroughly inspected to
insure that they are capable of carrying the weight of
the installing unit.
MOUNTING THE UNIT
1. These units are secured by wall mounting brackets
which secure the unit to the outside wall surface at
both sides. A bottom mounting bracket is provided
for ease of installation, but is not required.
2. The unit itself is suitable for “0” inch clearance, but
the supply air duct flange and the first 3 feet of supply
air duct require a minimum of 1/4 inch clearance to
combustible material. If a combustible wall, use a
minimum of 28½" x 8½" dimensions for sizing.
However, it is generally recommended that a 1-inch
clearance is used for ease of installation and
maintaining the required clearance to combustible
material.
WARNING
Failure to provide the 1/4 inch clearance
between the supply duct and a combustible
surface for the first 3 feet of duct can result in
fire.
3. Locate and mark lag bolt locations and bottom
mounting bracket location. See Figure 3.
4. Mount bottom mounting bracket, if used The supply
air opening would then be 30" x 10". See Figures 3
and 4 for details.
5. Hook top rain flashing under back bend of top. Top
rain flashing is shipped secured to the right side of the
back.
6. Position unit in opening and secure with 5/16 lag
bolts; use 7/8 inch diameter flat washers on the lag
bolts.
7. Secure rain flashing to wall and caulk across entire
length of top. See Figure 3.
8. For additional mounting rigidity, the return air and
supply air frames or collars can be drilled and
screwed or welded to the structural wall itself
(depending upon wall construction). Be sure to
observe required clearance of combustible wall.
9. On side-by-side installations, maintain a minimum of
20 inches clearance on right side to allow access to
heat strips and control panel and to allow proper
airflow to the outdoor coil. Additional clearance may
be required to meet local or national codes.
TOP OUTLET ONLY
1. Remove airframe angles from the back of the unit.
2. Coat angles with two 1/8" beads of silicone as shown.
Silicone is shipped in the control panel. See Figure 5.
3. Secure angles to the top of the unit with 14 screws
provided. Use of prepunched holes provided. Do not
relocate. See Figure 5.
4. After installation duct work, seal around airframe and
duct work to provide a rain tight seal.
5. It is strongly recommended, but not required, that this
unit be installed under a soffit area large enough to
shield the top of the unit. See Figure 6.
WIRING — MAIN POWER
Refer to the unit rating plate for wire sizing information
and maximum fuse or “HACR Type” circuit breaker
size. Each outdoor unit is marked with a “Minimum
Circuit Ampacity”. This means that the field wiring
used must be sized to carry that amount of current.
Depending on the installed KW of electric heat, there
may be two field power circuits required. If this is the
case, the unit serial plate will so indicate. All models
are suitable only for connection with copper wire. Each
unit and/or wiring diagram will be marked “Use Copper
Conductors Only”. These instructions must be adhered
to. Refer to the National Electrical Code (NEC) for
complete current carrying capacity data on the various
insulation grades of wiring material. All wiring must
conform to NEC and all local codes.
Manual 2100-404E
Page8 of 19
The electrical data lists fuse and wire sizes (75ºC copper)
for all models, including the most commonly used heater
sizes. Also shown are the number of field power circuits
required for the various models with heaters.
The unit rating plate lists a “Maximum Time Delay Relay
Fuse” or “HACR Type” circuit breaker that is to be used
with the equipment. The correct size must be used for
proper circuit protection and also to assure that there will
be no nuisance tripping due to the momentary high
starting current of the compressor motor.
The disconnect access door on this unit may be locked to
prevent unauthorized access to the disconnect. To
convert for the locking capability, bend the tab located in
the bottom left hand corner of the disconnect opening
under the disconnect access panel straight out. This tab
will now line up with the slot in the door. When shut, a
padlock may be placed through the hole in the tab
preventing entry.
LOW VOLTAGE CONNECTIONS
These units use a grounded 24 volt AC low voltage
circuit.
The "R" terminal is the hot terminal and the "C"
terminal is grounded.
"G" terminal is the fan input.
"Y" terminal is the compressor input for cooling.
"W1" terminal is the 1st stage electric heat. The
reversing valve must be energized for heating mode.
"W2" terminal is second stage heat (if equipped).
"F" terminal is the ventilation input. This terminal
energizes any factory installed ventilation option.
WIRING — LOW VOLTAGE WIRING
230/208V, 1 phase and 3 phase equipment dual primary
voltage transformers. All equipment leaves the factory
wired on 240V tap. For 208V operation, reconnect from
240V to 208V tap. The acceptable operating voltage
range for the 240 and 208V taps are:
TABLE 4
OPERATING VOLTAGE RANGE
PATEGNAR
V042612–352
V802781–022
NOTE: The voltage should be measured a the
field power connection point in the unit
and while the unit is operating at full load
(maximum amperage operating condition.)
Five (5) wires should be run from thermostat subbase to
the 24V terminal board in the unit. A five conductor, 18
gauge copper, color-coded thermostat cable is
recommended. The connection points are shown in
Figure 8.
LOW VOLTAGE CONNECTIONS
FOR DDC CONTROL
Fan OnlyEnergize G
Cooling ModeEnergize Y, G
1st Stage HeatingEnergize W1
2nd Stage HeatingEnergize W1, W2
(if employed)
VentilationEnergize G, F
TABLE 5
THERMOSTAT WIRE SIZE
remrofsnarT
AVALFeguaGeriW
553.2
TABLE 6
WALL THERMOSTAT
tatsomrehTserutaeFetanimoderP
mumixaM
ecnatsiD
teeFnI
eguag02
eguag81
eguag61
eguag41
eguag21
54
06
001
061
052
750-3048
3511D0225HT
850-3048
1511D0225HT
060-3048
)544-0211(
taeHegats1,looCegats1
elbammargorP-noNcinortcelE
revoegnahclaunaMrootuA
taeHegats2,looCegats2
elbammargorP-noNcinortcelE
revoegnahclaunaMrootuA
taeHegats3;looCegats3
cinortcelEelbammargorP-noN/elbammargorP
lanoitnevnoCroPH
revoegnahclaunaMrootuA
Manual2100-404E
Page9 of 19
FIGURE 3
MOUNTING INSTRUCTIONS
Manual 2100-404E
Page10 of 19
FIGURE 4
WALL-MOUNTING INSTRUCTIONS
SEE FIGURE 3 – MOUNTING INSTRUCTIONS
FIGURE 5
WALL-MOUNTING INSTRUCTIONS
SEE UNIT DIMENSIONS, FIGURE 1,
FOR ACTUAL DIMENSIONS
SEE FIGURE 1 FOR
DUCT DIMENSIONS
Manual2100-404E
Page11 of 19
FIGURE 6
COMMON WALL-MOUNTING INSTALLATIONS
Manual 2100-404E
Page12 of 19
FIGURE 7
ELECTRIC HEAT CLEARANCE
Side section view of supply air duct for
wall mounted unit showing 1/4 inch
clearance to combustible surfaces.
WARNING
A
minimum
the supply air duct and combustible materials. This is required
for the first 3 feet of ducting.
It is important to insure that the 1/4 inch minimum spacing is
maintained at all points.
Failure to do this could result in overheating the combustible
material and may result in a fire causing damage, injury or death.
of 1/4 inch clearance must be maintained between
Manual2100-404E
Page13 of 19
FIGURE 8
LOW VOLTAGE WIRING
Manual 2100-404E
Page14 of 19
START UP
IMPORTANT INSTALLER NOTE
For improved start-up performance, wash the indoor coil
with a dishwasher detergent.
HIGH PRESSURE SWITCH
The WA372 models are supplied with a remote reset
high pressure switch. If tripped, this pressure switch
may be reset by turning the thermostat off then back on
again.
THREE PHASE SCROLL COMPRESSOR
START UP INFORMATION
Scroll compressors, like several other types of
compressors, will only compress in one rotational
direction. Direction of rotation is not an issue with
single phase compressors since they will always start
and run in the proper direction.
However, three phase compressors will rotate in either
direction depending upon phasing of the power. Since
there is a 50-50 chance of connecting power in such a
way as to cause rotation in the reverse direction,
verification of proper rotation must be made. All three
phase units incorporate a phase monitor to ensure proper
field wiring. See the Phase Monitor section in this
manual.
PHASE MONITOR
All units with three phase compressors are equipped
with a 3 phase line monitor to prevent compressor
damage due to phase reversal.
The phase monitor in this unit is equipped with two
LEDs. If the Y signal is present at the phase monitor
and phases are correct the green LED will light.
If phases are reversed, the red fault LED will be lit and
compressor operation is inhibited.
If a fault condition occurs, reverse two of the supply
leads to the unit. Do not reverse any of the unit factory
wires as damage may occur.
SERVICE HINTS
1. Caution homeowner to maintain clean air filters at all
times. Also, not to needlessly close off supply and
return air registers. This reduces airflow through the
system, which shortens equipment service life as well
as increasing operating costs.
2. Check all power fuses or circuit breakers to be sure
they are the correct rating.
3. Periodic cleaning of the outdoor coil to permit full
and unrestricted airflow circulation is essential.
Verification of proper rotation must be made any time a
compressor is change or rewired. If improper rotation is
corrected at this time there will be no negative impact on
the durability of the compressor. However, reverse
operation for over one hour may have a negative impact
on the bearing due to oil pump out.
NOTE: If compressor is allowed to run in reverse
rotation for several minutes, the compressor's
internal protector will trip.
All three phase ZR3 compressors are wired identical
internally. As a result, once the correct phasing is
determined for a specific system or installation,
connecting properly phased power leads to the same
Fusite terminal should maintain proper rotation
direction.
Verification of proper rotation direction is made by
observing that suction pressure drops and discharge
pressure rises when the compressor is energized.
Reverse rotation also results in an elevated sound level
over that with correct rotations, as well as, substantially
reduced current draw compared to tabulated values.
The direction of rotation of the compressor may be
changed by reversing any two line connections to the
unit.
SEQUENCE OF OPERATION
Cooling—Circuit R-Y makes at thermostat pulling in
compressor contactor, starting the compressor and
outdoor motor. The G (indoor motor) circuit is
automatically completed on any call for cooling
operation or can be energized by manual fan switch on
subbase for constant air circulation. On all 230 volt
units, there is a one-minute off delay on the blower
motor. 460 volt models do not have an off delay. On a
call for heating, circuit R-W1 make at the thermostat
pulling in heat contact for the strip heat and blower
operation. On a call for second stage heat, R-W2 makes
bringing on second heat contactor, if so equipped.
Manual2100-404E
Page15 of 19
COMPRESSOR CONTROL MODULE
The compressor control module is optional on the
models covered by this manual. The compressor control
is an anti-short cycle/lockout timer with high and low
pressure switch monitoring and alarm relay output.
Alarm Relay Output
Alarm terminal is output connection for applications
where alarm relay is employed. This terminal is
powered whenever compressor is locked out due to HPC
or LPC sequences as described.
Adjustable Delay On Make And Break Timer
On initial power up or any time power is interrupted to
the unit, the delay on make period begins, which will be
2 minutes plus 10% of the delay on break setting. When
the delay on make is complete and the high pressure
switch (and low pressure switch if employed) is closed,
the compressor contactor is energized. Upon shutdown,
the delay or break timer starts and prevents restart until
the delay on break and delay on make periods have
expired.
During routine operation of the unit with no power
interruptions the compressor will operate on demand
with no delay.
High Pressure Switch and Lockout Sequence
If the high pressure switch opens, the compressor
contactor will de-energize immediately. The lockout
timer will go into a soft lockout and stay in soft lockout
until the high pressure switch closes and the delay on
break time has expired. If the high pressure switch
opens again in this same operating cycle, the unit will go
into manual lockout condition and the alarm relay circuit
will energize. Recycling the wall thermostat resets the
manual lockout.
Low Pressure Switch, Bypass, and Lockout
Sequence
If the low pressure switch opens for more than 120
seconds, the compressor contactor will de-energize and
go into a soft lockout. Regardless the state of the low
pressure switch, the contactor will reenergize after the
delay on make time delay has expired. If the low
pressure switch remains open, or opens again for longer
than 120 seconds the unit will go into manual lockout
condition and the alarm relay circuit will energize.
Recycling the wall thermostat resets the manual lockout.
NOTE: Both high and low pressure switch controls are
inherently automatic reset devices. The high
pressure switch and low pressure switch cut out
and cut in settings are fixed by specific air
conditioner or heat pump unit model. The
lockout features, both soft and manual, are a
function of the Compressor Control Module.
ADJUSTMENTS
Adjustable Delay on Make and Delay on Break
Timer
The potentiometer is used to select Delay on Break time
from 30 seconds to 5 minutes. Delay on Make (DOM)
timing on power-up and after power interruptions is
equal to 2 minutes plus 10% of Delay on Break (DOB)
setting:
0.5 minute (30 seconds) DOB = 123 second DOM
1.0 minute (60 seconds) DOB = 126 second DOM
2.0 minute (120 seconds) DOB = 132 second DOM
3.0 minute (180 seconds) DOB = 138 second DOM
4.0 minute (240 seconds) DOB = 144 second DOM
5.0 minute (300 seconds) DOB = 150 second DOM
During routine operation of the unit with no power
interruptions, the compressor will operate on demand
with no delay.
Typical Settings for Dual Unit Installation:
Unit 1: DOB set at 2 minutes, and DOM is 132 seconds
Unit 2: DOB set at 4 minutes, and DOM is 144 seconds
PRESSURE SERVICE PORTS
High and low pressure service ports are installed on all
units so that the system operating pressures can be
observed. Pressure tables can be found later in the
manual covering all models. It is imperative to match
the correct pressure table to the unit by model number.
Manual 2100-404E
Page16 of 19
TROUBLESHOOTING
ledoM
1
detaR
MFC
1
detaR
PSE
dednemmoceR
egnaRwolfriA
203AW
000,104.003,1– 039
173AW
001,103.053,1–039
FAN BLADE SETTING DIMENSIONS
Shown in the drawing below are the correct fan blade
setting dimensions for proper air delivery across the
outdoor coil.
Any service work requiring removal or adjustment in the
fan and/or motor area will require that the dimensions
below be checked and blade adjusted in or out on the
motor shaft accordingly.
FIGURE 9
FAN BLADE SETTING
AIRFLOW
TABLE 7
FAN BLADE DIMENSION
ledoMAnoisnemiD
203AW
273AW
52.1
MIS-1724
The suction line temperatures in Table 8 are based upon
80ºF dry bulb/67ºF wet bulb (50 percent R.H.)
temperature and rated airflow across the evaporator
during cooling cycle.
TABLE 9
INDOOR BLOWER PERFORMANCE
CFM AT 230 VOLTS
deepShgiHdeepSwoL
lioCyrDlioCteWlioCyrDlioCteW
"A"
.P.S.E
O
HnI
2
0.593,1513,1059539
1.043,1072,1039519
2.582,1091,1019588
3.502,1001,1558038
4.011,1000,1008557
5.500,1078------
TABLE 10
RATED CFM AND ESP
273AW,203AW
REMOVAL OF FAN SHROUD
1. Disconnect all power to unit.
2. Remove the screws holding both grills – one on each
side of unit – and remove grills.
3. Remove screws holding fan shroud to condenser and
bottom – 9 screws.
4. Unwire condenser fan motor.
5. Slide complete motor, fan blade, and shroud assembly
out the left side of the unit.
6. Service motor/fan as needed.
7. Reverse steps to reinstall.
REFRIGERANT CHARGE
The correct system R-22 charge is shown on the unit
rating plate. Optimum unit performance will occur with
a refrigerant charge resulting in a suction line
temperature (6 inches from compressor) as shown in
Table 8.
TABLE 8
SUCTION LINE TEMPERATURES
detaR
sledoM
203AW000,195–6566–46
273AW001,195–7546–26
wolfriA
F°59
.pmeTDO
F°28
.pmeTDO
1 Rated CFM and ESP on high speed tap
TABLE 11
MAXIMUM ESP OF OPERATION
ELECTRIC HEAT ONLY
ledoMteltuOtnorFteltuOpoT
deepS
WK
Z0A
50A
80A
01A
51A
Z0B
60B
90B
51B
Z0C
60C
90C
51C
woL
deepS
05.
05.
05.
54.
53.
05.
04.
05.
03.
05.
05.
04.
53.
hgiH
deepS
05.
05.
0
5.
05.
04.
05.
05.
05.
54.
05.
05.
05.
54.
woL
05.
54.
---
53.
---
05.
---
04.
---
05.
---
04.
---
Manual2100-404E
Page17 of 19
deepS
hgiH
deepS
05.
05.
---
05.
---
05.
---
54.
---
05.
---
54.
---
TABLE 12
COOLING PRESSURE
Outdoor Temperature °F
riAnruteR
ledoM
203AW
273AW
Low side pressure ± 2 psig
High side pressure ± 5 psig
Tables are based upon rated CFM (airflow) across the evaporator coil and should be found under section titled
"Refrigerant Charge" elsewhere in manual. If there is any doubt as to correct charge being in the system, the
charge should be removed, system evacuated and recharged to serial plate instructions.