American Standard 2A7A8 Assembly instructions

© 2008 American Standard Heating & Air Conditioning
Since the manufacturer has a policy of continuous product
and product data improvement, it reserves the right to
change design and specifications without notice.
11-AC14D1-6
These instructions do not cover all variations in systems nor
provide for every possible contingency to be met in connec-
tion with installation. All phases of this installation must
comply with NATIONAL, STATE AND LOCAL CODES. Should
further information be desired or should particular problems arise
which are not covered sufficiently for the purchaser’s purposes, the
matter should be referred to your installing dealer or local distributor.
A. GENERAL
▲ WARNING:
This information is intended
for use by individuals possessing adequate backgrounds of
electrical and mechanical experience. Any attempt to re-
pair a central air conditioning product may result in
personal injury and or property damage. The manufac-
turer or seller cannot be responsible for the interpretation
of this information, nor can it assume any liability in
connection with its use.
NOTE: THE MANUFACTURER HAS ALWAYS RECOM-
MENDED INSTALLING AMERICAN STANDARD HEATING
AND AIR CONDITIONING APPROVED MATCHED INDOOR
AND OUTDOOR SYSTEMS.
THE BENEFITS OF INSTALLING APPROVED MATCHED
SYSTEMS ARE MAXIMUM EFFICIENCY, OPTIMUM PER-
FORMANCE AND BEST OVERALL SYSTEM RELIABILITY.
Check for transportation damage after unit is uncrated. Report
promptly, to the carrier, any damage found to the unit.
To determine the electrical power requirements of the unit, refer
to the nameplate of the unit. The electrical power available must
agree with that listed on the nameplate.
B. LOCATION AND PREPARATION OF THE UNIT
1. When removing unit from the pallet, notice the tabs on the
basepan. Remove tabs by cutting with a sharp tool as shown in
Figure 2 (see page 2).
2. The unit should be set on a level support pad at least as large
as the unit base pan, such as a concrete slab. If this is not the
application used please reference ALG-APG0*-EN (*latest revi-
sion number).
3. The support pad must NOT be in direct contact with any
structure. Unit must be positioned a minimum of 12" from any
wall or surrounding shrubbery to insure adequate airflow. Clear-
ance must be provided in front of control box (access panels) & any
other side requiring service access to meet National Electrical
Code. Also, the unit location must be far enough away from any
structure to prevent excess roof run-off water from pouring di-
rectly on the unit. When choosing the location of the unit(s), sound
transmission through air and refrigerant lineset should be taken
into consideration. It is recommended to locate unit(s) away from
areas (bedrooms, etc.) where such sound could be objectionable.
4. The top discharge area must be unrestricted for at least
five (5) feet above the unit.
5. When the outdoor unit is mounted on a roof, be sure the roof
will support the unit’s weight. Properly selected isolation is
recommended to prevent transmission to the building structure.
6. The maximum length of refrigerant lines from outdoor to
indoor unit should NOT exceed sixty (60) feet.
7. If outdoor unit is mounted above the air handler, maximum lift
should not exceed twenty-five (25) feet (suction line). If air handler
is mounted above condensing unit, maximum lift should not
exceed twenty-five (25) feet (liquid line).
8. Locate and install indoor coil or air handler in accordance with
instruction included with that unit.
NOTE: Refer to “Refrigerant Piping Software” Pub.
No. 32-3312-0*, and “Refrigerant Piping Manual” Pub.
No. 32-3009-0* (the position of the * denotes latest revision
number).
C. INSTALLING REFRIGERANT LINES
▲ CAUTION:
If using existing refrigerant lines
make certain that all joints are brazed, not soldered.
Condensing units have provisions for braze connections.
Pressure taps are provided on the service valves of outdoor unit for
compressor suction and liquid pressures.
Condensing Units
INSTALLER'S GUIDE
ALL phases of this installation must comply with NATIONAL, STATE AND LOCAL CODES
5 FT.
ABOVE UNIT —
UNRESTRICTED
1
Models: 2A7A8 with AccuLink™and Charge Assist™
IMPORTANT — This Document is customer property and is to remain with this unit. Please return to service information pack
upon completion of work.

PAGE 2 Pub. No. 11-AC14D1-6
INSTALLER'S GUIDE
The indoor end of the recommended refrigerant line sets may be
straight or with a 90 degree bend, depending upon situation
requirements. This should be thoroughly checked out before or-
dering refrigerant line sets.
The gas line must always be insulated.
▲
C
A
U
TI
O
N:
In scroll compressor applications,
dome temperatures may be hot. Do not touch top of com-
pressor, may cause minor to severe burning.
The units are factory charged with the system charge required
when using fifteen (15) feet of rated connecting line. Unit name-
plate charge is with twenty-five (25) feet of line set.
Final refrigerant charge adjustment is necessary. Use the
Charging Information in the outdoor unit Service Facts.
1. Determine the most practical way to run the lines.
2. Consider types of bends to be made and space limitations.
NOTE: Large diameter tubing will be very difficult to rebend once
it has been shaped.
3. Determine the best starting point for routing the refrigerant
tubing — INSIDE OR OUTSIDE THE STRUCTURE.
4. Provide a pull-thru hole of sufficient size to allow both liquid
and gas lines.
5. Be sure the tubing is of sufficient length.
6. Uncoil the tubing — do not kink or dent.
7. Route the tubing making all required bends and properly
secure the tubing before making connections.
8. To prevent a noise within the building structure due to vibra-
tion transmission from the refrigerant lines, the following precau-
tions should be taken:
a. When the refrigerant lines have to be fastened to floor joists
or other framing in a structure, use isolation type hangers.
b. Isolation hangers should also be used when refrigerant
lines are run in stud spaces or enclosed ceilings.
c. Where the refrigerant lines run through a wall or sill, they
should be insulated and isolated.
d. Isolate the lines from all ductwork.
D. SERVICE VALVE OPERATION
BRASS LIQUID AND GAS LINE SERVICE VALVES
The Brass Liquid and Gas Line Service Valves are factory shipped in
the seated position to hold factory charge. The pressure tap service
port (when depressed) opens only to the field brazing side of the valve
when the valve is in the seated position. The liquid line valve is not
a back seating valve (see WARNING at top of next column).
▲ WARNIN
G
:
Extreme caution should be ex-
ercised when opening the Liquid and Gas Line Service
Valves. Turn valve stem counterclockwise only until the
stem contacts the rolled edge. (See Figures 3 and 5) No
torque is required. Failure to follow this warning will
result in abrupt release of system charge and may result in
personal injury and/or property damage.
BRASS GAS LINE BALL SERVICE VALVE
The Brass Gas Line Ball Service Valve is shipped in the closed
position to hold the factory refrigerant charge. The pressure tap
service port (when depressed) opens only to the field brazing side
when the valve is in the closed position.
The Gas Line Service Valve is full open with a 1/4 turn. See Figure 4.
BRAZING REFRIGERANT LINES
1. Remove lower access cover to access service valves.
2. Before brazing, remove plugs from external copper stub tubes.
Clean internal and external surfaces of stub tubes prior to brazing.
3. Cut and fit tubing, minimizing the use of sharp 90° bends.
4. Insulate the entire gas line and its fittings.
5. Do NOT allow uninsulated liquid line to come in direct contact
with bare gas line.
6. Precautions should be taken to avoid heat damage to
the pressure tap valve core during brazing. It is recom-
mended that the pressure tap port valve core be removed
and a wet rag wrapped around the valve body.
NOTICE: Use care to make sure that no moisture enters pressure
tap port, while wet rag is being used.
NOTICE: Precautions should be taken to avoid heat damage to
basepan during brazing. It is recommended to keep the flame
directly off of the basepan.
7. Use a Dry Nitrogen Purge and Brazing Alloy without flux when
brazing the field line to the copper factory connection. Flow dry
nitrogen into either valve pressure tap port, thru the tubing and
out the other port while brazing.
8. Braze using accepted good brazing techniques.
LEAK CHECK
IMPORTANT: Replace pressure tap port valve core before at-
taching hoses for evacuation.
After the brazing operation of refrigerant lines to both the outdoor
and indoor unit is completed, the field brazed connections must be
checked for leaks. Pressurize through the service valve ports, the
indoor unit and field refrigerant lines with dry nitrogen to 350-400 psi.
BASEPAN TAB REMOVAL
2
LIQUID LINE SERVICE VALVE
3

Pub. No. 11-AC14D1-6 PAGE 3
INSTALLER'S GUIDE
8. Close valve on HCFC-22 supply cylinder. Close valves on
manifold gauge set and remove refrigerant charging hoses from
liquid and gas pressure tap ports.
NOTE: A 3/16" Allen wrench is required to open liquid line
service valve. A 1/4" Open End or Adjustable wrench is
required to open gas line valve. A 3/4" Open End wrench is
required to take off the valve stem cap.
9. The liquid line shut-off valve can now be opened. Remove shut-
off valve cap. Fully insert hex wrench into the stem and back out
counterclockwise until valve stem just touches rolled edge (ap-
proximately five [5] turns) observing WARNING statement on
page 2. See Figure 3.
10. Replace liquid service pressure tap port cap and valve stem
cap. These caps MUST BE REPLACED to prevent leaks. Re-
place valve stem and pressure tap cap finger tight, then tighten an
additional 1/6 turn.
11. The gas valve can now be opened. For a ball type gas valve,
open the gas valve by removing the shut-off valve cap and turning
the valve stem 1/4 turn counterclockwise, using 1/4" Open End or
Adjustable wrench. See Figure 4. For brass gas line service valve
opening, follow 9 and 10 above. See Figure 5.
12. The gas valve is now open for refrigerant flow. Replace valve
stem cap to prevent leaks. Again, these caps MUST BE RE-
PLACED to prevent leaks. Replace valve stem and pressure tap
cap finger tight, then tighten an additional 1/6 turn. See Figure 4.
If refrigerant lines are longer than 15 feet and/or a different
size than recommended, it will be necessary to adjust system
refrigerant charge upon completion of installation. See the unit
Service Facts.
E. ELECTRICAL CONNECTIONS
▲ WARNING:
When installing or servicing
this equipment, ALWAYS exercise basic safety precau-
tions to avoid the possibility of electric shock.
1. Power wiring and grounding of equipment must comply with
local codes.
2. Power supply must agree with equipment nameplate.
3. Install a separate disconnect switch at the outdoor unit.
4. Ground the outdoor unit per local code requirements.
5. Provide flexible electrical conduit whenever vibration trans-
mission may create a noise problem within the structure.
6. The use of color coded low voltage wire is recommended to
simplify connections between the outdoor unit, the AccuLink™
control and the indoor unit.
Table 1 — NEC Class II Wiring
NOTE: The maximum total cable length for the entire Comfort
Control communicating system is 500 ft. 18 AWG.
7. Mount the AccuLink™ control in accordance with instruction
included with the AccuLink™ control. Wire per appropriate hookup
diagram (included in these instructions).
F. COMPRESSOR START-UP
After all electrical wiring is complete, SET THE ACCULINK™
CONTROL SWITCH IN THE OFF POSITION SO COMPRES-
SOR WILL NOT RUN, and apply power by closing the system
Use soap bubbles or other leak-checking methods to see that all field
joints are leak-free! If not, release pressure; then repair!
SYSTEM EVACUATION
NOTE: Since the outdoor unit has a refrigerant charge, the gas and
liquid line valves must remain closed.
1. Upon completion of leak check, evacuate the refrigerant lines and
indoor coil before opening the gas and liquid line valves.
2. Attach appropriate hoses from manifold gauge to gas and
liquid line pressure taps.
NOTE: Unnecessary switching of hoses can be avoided and
complete evacuation of all lines leading to sealed system can be
accomplished with manifold center hose and connecting branch
hose to a cylinder of HCFC-22 and vacuum pump.
3. Attach center hose of manifold gauges to vacuum pump.
4. Evacuate until the micron gauge reads no higher than
350 microns.
5. Close off valve to vacuum pump and observe the micron gauge.
If gauge pressure rises above 500 microns in one (1) minute, then
evacuation is incomplete or system has a leak.
6. If vacuum gauge does not rise above 500 microns in one (1)
minute, the evacuation should be complete.
7. With vacuum pump and micron gauge blanked off, open valve
on HCFC-22 cylinder and charge refrigerant lines and indoor coil
with vapor to tank pressure of HCFC-22 supply.
NOTE: DO NOT VENT REFRIGERANT INTO THE
ATMOSPHERE.
CAP 1/4 TURN ONLY
COUNTERCLOCKWISE
FOR FULL OPEN
POSITION
VALVE STEM
GAS LINE CONNECTION
UNIT SIDE
OF VALVE
PRESSURE TAP PORT
GAS LINE BALL SERVICE VALVE
4
GAS LINE SERVICE VALVE
5
AccuLink™ Control Wiring
WIRE SIZE MAX. WIRE LENGTH
18 AWG 250 FT

PAGE 4 Pub. No. 11-AC14D1-6
INSTALLER'S GUIDE
REFRIGERANT CIRCUIT
Liquid Pressure Too High
Liquid Pressure Too Low
Suction Pressure Too High
Suction Pressure Too Low
Liquid Refrig. Floodback TXV System
I.D. Coil Frosting
Compressor Runs Inadequate or No Cooling
ELECTRICAL
Compressor & O.D. Fan Do Not Start
Compressor Will Not Start But O.D. Fan Runs
O.D. Fan Won’t Start
Compressor Hums But Won’t Start
Compressor Cycles on IOL
I.D. Blower Won’t Start
SYSTEM FAULTS
P - Primary Causes S - Secondary Causes
P
P
P
S
S
PS
S
S
S
S
P
S
S
S
P
P
P
S
S
S
S
S
S
S
P
P
P
S
P
P
S
S
S
P
P
P
P
P
P
P
P
P
P
S
S
S
S
P
P
PP
P
S
S
PSPSS S S S
S
S
P
P
P
P
P
S
P
P
POWER SUPPLY
HIGH VOLTAGE WIRING
COMPR. IOL
RUN CAPACITOR
START CAPACITOR
START RELAY
CONTACTOR CONTACTS
LOW VOLTAGE WIRING
CONTROL TRANSFORMER
CONTACTOR COIL
LOW VOLTAGE FUSE
STUCK COMPRESSOR
INEFFICIENT COMPRESSOR
REFRIGERANT UNDERCHARGE
REFRIGERANT OVERCHARGE
EXCESSIVE EVAP. LOAD
NONCONDENSABLES
RESTRICTED O.D. AIRFLOW
O.D. AIR RECIRCULATION
TXV STUCK OPEN
SUPERHEAT
RESTRICTED I.D. AIRFLOW
REF. CIRCUIT RESTRICTIONS
O.D. FAN SPEED SWITCH
TROUBLESHOOTING CHART — WHAT TO CHECK
B
BK
Y2
Y1
O
R
D
W1
W3
G
W2
B
D
B
R
D
X2
Y2
Y1
O
AccuLink™
COMFORT
CONTROL
24VAC HOT
24VAC
Common
DATA
AccuLink™
INDOOR
UNIT
AccuLink™
OUTDOOR
UNIT
FIELD WIRING DIAGRAM
COMMUNICATING INDOOR UNIT – COMMUNICATING OUTDOOR UNIT
6
main disconnect switch. This will activate the compressor sump
heat (where used). Do not change the AccuLink™ control switch
until power has been applied for one (1) hour. Following this
procedure will prevent potential compressor overload trip at the
initial start-up.
G. OPERATIONAL AND CHECKOUT PROCEDURES
Final phases of this installation are the unit Operational and
Checkout Procedures which are found in this instruction on
page 7. To obtain proper performance, all units must be operated
and charge adjustments made in accordance with procedures
found in the Service Facts.
NOTE: Perform a final unit inspection to be sure that factory
tubing has not shifted during shipment. Adjust tubing if necessary
so tubes do not rub against each other when the unit runs. Also be
sure that wiring connections are tight and wire routing is secure.
H. SEACOAST SALT SHIELD
BAYSEAC001 (Seacoast Kit) is available for application on units
installed within one mile of salt water, including seacoasts and
inland waterways.
I. TROUBLESHOOTING CHART
NOTE: For non-communicating systems use
24-volt harness accessory BAYACHP024A.

Pub. No. 11-AC14D1-6 PAGE 5
INSTALLER'S GUIDE
DIRECTION FOR CHARGE ASSIST™
NOTE: Outdoor Temperature (ODT) must be between 65°F
and 100°F.
Be sure to set Dip Switches for Line Length and Lift before
entering Charge Assist™ Mode. (See Subcool Charging Table
Corrections for Line Length and Rise in the Service Facts for the
outdoor unit.)
To enter Charge Assist™ Mode, press the MODE button for at
least one (1) second. The on-board LEDs will indicate if the system
is capable of continuing. For a detailed description of on-board
LEDs and their function, see the Charge Assist™ Procedure
(18-AC72D1-*) contained in the Outdoor Unit (the position of the
* denotes the latest revision number).
The system will take approximately 12-20 minutes to stabilize
before the charge can be checked by Charge Assist™. Once the
system is stabilized, watch to see which LED turns on next. If the
system charge is correct, the “CHARGED” LED will turn on and
remain on for one (1) hour. Once charged, the system will exit
Charge Assist™ and control will return to the Comfort Control.
If the system charge is low, the “ADD” LED will turn on and stay
on up to one (1) hour or until enough refrigerant is added to reach the
required system charge level and turn on the “CHARGED” LED.
When the “ADD” LED is on, the charging solenoid output will be
active. This feature works to automatically control refrigerant
flow with BAYCAKT001.
If the system charge is high, the “REC” LED will turn on and the
unit will exit Charge Assist™. You must recover refrigerant from
the system before re-entering Charge Assist™.
For instructions on the Charge Assist™ tool BAYCAKT001, see
the Installer's Guide 18-HH15D1-* (the position of the * denotes
the latest revision number).
CHARGE ASSIST™ CHARGE ASSIST™ PORT
78
For additional information on manual charging, please see the Service Facts shipped with the outdoor unit.
NOTE: Charge Assist™ port is
designed for liquid refrigerant charging.

PAGE 6 Pub. No. 11-AC14D1-6
INSTALLER'S GUIDE
From Dwg. 21D152862 Rev. 20
2A7A8 OUTLINE DRAWING
NOTE: ALL DIMENSIONS ARE IN MM (INCHES).
MODELS BASE FIG. A B C D E F G H J K
2A7A8030C 4 1 1045 (41-1/8) 946 (37-1/4) 870 (34-1/4) 7/8 3/8 152 (6) 98 (3-7/8) 219 (8-5/8) 86 (3-3/8) 711 (28)
2A7A8036C 4 1 1045 (41-1/8) 946 (37-1/4) 870 (34-1/4) 7/8 3/8 152 (6) 98 (3-7/8) 219 (8-5/8) 86 (3-3/8) 711 (28)
2A7A8048C 4 1 1045 (41-1/8) 946 (37-1/4) 870 (34-1/4) 1-1/8 3/8 152 (6) 98 (3-7/8) 219 (8-5/8) 86 (3-3/8) 711 (28)
2A7A8060C 4 1 1045 (41-1/8) 946 (37-1/4) 870 (34-1/4) 1-1/8 3/8 152 (6) 98 (3-7/8) 219 (8-5/8) 86 (3-3/8) 711 (28)

Pub. No. 11-AC14D1-6 PAGE 7
INSTALLER'S GUIDE
8. Supply registers and return grilles
open and unobstructed ................................................... [ ]
9. Return air filter installed .................................................. [ ]
10. AccuLink™ control is accurate.
Check against a reliable thermometer.
Adjust per instructions with AccuLink™ control ............. [ ]
11. Is correct speed tap being used?
(Indoor blower motor)...................................................... [ ]
12. Operate complete system in each mode
to insure safe operation. ................................................. [ ]
1. Refrigerant Line, Leak checked ...................................... [ ]
2. Suction Lines and Fittings properly insulated ................ [ ]
3. Have all Refrigerant Lines been secured
and isolated properly? .................................................... [ ]
4. Have passages through masonry been sealed?
If mortar is used, prevent mortar from coming into
direct contact with copper tubing .................................... [ ]
5. Verify tightness of all electrical connects ....................... [ ]
6. Observe outdoor fan during on cycle for
clearance and smooth operation .................................... [ ]
7. Indoor coil drain line drains freely.
Pour water into drain pan................................................ [ ]
CHECKOUT PROCEDURE
After installation has been completed, it is recommended that the entire system be checked against the following list:
MOUNTING HOLE LOCATION
NOTE: ALL DIMENSIONS ARE IN MM (INCHES).
From Dwg. D152989 Rev. 2

Pub. No. 11-AC14D1-6
02/08
Technical Literature - Printed in U.S.A.
American Standard Heating & Air Conditioning
Troup Highway
Tyler, TX 75707-9010