These publications can help when installing the heat
pump. They can usually be found at the local library
or purchased directly from the publisher. Be sure to
consult the 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:
ACCA Air Conditioning Contractors of America
1712 New Hampshire Ave. N.W.
Washington, DC 20009
Telephone: (202) 483-9370
Fax: (202) 234-4721
ANSI American National Standards Institute
11 West Street, 13th Floor
New York, NY 10036
Telephone: (212) 642-4900
Fax: (212) 302-1286
ASHRAE American Society of Heating, Refrigeration
and Air Conditioning Engineers, Inc.
Batterymarch Park
P.O. Box 9101
Quincy, MA 02269-9901
Telephone: (800) 344-3555
Fax: (617) 984-7057
Manual 2100-654C
Page 3 of 34
WALL MOUNT GENERAL INFORMATION
HEAT PUMP WALL MOUNT MODEL NOMENCLATURE
W 42 H A – A 10 X X X X X A
MODEL NUMBER
CAPACITY
18 - 1½ Ton
24 - 2 Ton
30 - 2½ Ton
36 - 3 Ton
42 - 3½ Ton
48 - 4 Ton
60 - 5 Ton
Insert “D” for dehumidification with hot gas reheat. Reference Form 7960-702 for complete details.
For 0 KW and circuit breakers (230/208 volt) or toggle disconnect (460V) applications, insert 0Z in the KW field of the model number.
NOTE: Vent options X, B and M are without exhaust capability. May require separate field-supplied barometric relief in building.
H - Heat Pump
SPECIALTY PRODUCTS
(Non-Standard)
VENTILATION OPTIONS
X - Barometric Fresh Air Damper (Standard)
B - Blank-Off Plate
M - Motorized Fresh Air Damper
V - Commercial Ventilator - Motorized with Exhaust
S - Economizer (Std.) - Enthalpy
W - Economizer (Full Flow) - Enthalpy
T - Economizer (Full Flow) - Temperature
R - Energy Recovery Ventilator - Motorized with Exhaust
(See Spec. Sheet S3523)
SHIPPING DAMAGE
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.
REVISIONS
VOLTS & PHASE
A - 230/208/60/1
B - 230/208/60/3
C - 460/60/3
KW
COLOR OPTIONS
X - Beige (Standard)
1 - White
4 - Buckeye Gray
5 - Desert Brown
8 - Dark Bronze
FILTER OPTIONS
X - 1" Throwaway (Standard)
W - 1" Washable
P - 2" Pleated
OUTLET OPTIONS
X - Front
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.
CONTROL MODULES
(See Spec. Sheet S3523)
COIL OPTIONS
X - Standard
1 - Phenolic Coated Evaporator
2 - Phenolic Coated Condenser
3 - Phenolic Coated Evaporator
and Condenser
Size of unit for a proposed installation should be
GENERAL
based on heat loss/gain calculation made according
to methods of Air Conditioning Contractors of America
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
(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.
return ducts.
These instructions explain the recommended method
to install the air cooled self-contained unit and the
electrical wiring connections to the unit.
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
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.
equipment.
Manual 2100-654C
Page 4 of 34
Refer to Maximum ESP of Operation Electric Heat
Table 11 on page 32.
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" 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.
Models W18 and W24 are approved for 0" clearance to
the supply duct. For models W30, W36, W42, W48
and W60, a 1/4" clearance to combustible material for
the first 3' of duct attached to the outlet air frame is
required. See MOUNTING THE UNIT on page 6 and
Figures 3A – D (pages 8 – 11) and Figure 4 (page 12)
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.
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".
Any grille that meets with 5/8" louver criteria may be
used. It is recommended that Bard Return Air Grille
Kit RG-2W through RG-5W or RFG-2W through RFG5W 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.
NOTE: If no return air duct is used, applicable
installation codes may limit this cabinet to
installation only in a single story structure.
FILTERS
A 1" throwaway filter is standard with each unit. The
filter slides into position making it easy to service. This
filter can be serviced from the outside by removing the
filter access panel. A 1" washable filter and 2" pleated
filter are also available as optional accessories. The
internal filter brackets are adjustable to accommodate
the 2" filter by bending two tabs down on each side of
the filter support bracket.
FRESH AIR INTAKE
All units are built with fresh air inlet slots punched in
the service door.
If the unit is equipped with a 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 1).
All capacity, efficiency and cost of operation
information 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.
FIGURE 1
Fresh Air Damper
BLADE IS LOCKED CLOSED
FOR SHIPPING
MIS-938
Manual 2100-654C
Page 5 of 34
INSTALLATION
WALL MOUNTING INFORMATION
1. Two holes for the supply and return air openings
must be cut through the wall as shown in Figures
3A – D.
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.
3. Concrete block walls must be thoroughly inspected
to insure that they are capable of carrying the
weight of the installed unit.
NOTE: Before mounting the heat pump unit,
consideration should be given to the
condensate removal from the outdoor coil
when in heating mode. The unit must be
mounted high enough above grade to ensure
that ice will not build up under the unit and
come into contact with the base of the unit. If
allowed, this could cause damage to the coil
and other base components. Also, be sure
there are no air obstructions to the sides or
front of the unit, such as bushes or fences,
that would inhibit condenser airflow.
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, attached
to skid for shipping, is provided for ease of
installation, but is not required.
2. The unit itself is suitable for 0" clearance, but the
supply air duct flange and the first 3' of supply
air duct require a minimum of 1/4" clearance to
combustible material for model series W30, W36,
W42, W48 and W60. However, it is generally
recommended that a 1" clearance is used for
ease of installation and maintaining the required
clearance to combustible material. See Figures 3A
– D for details on opening sizes.
Minimum Clearances Required to
Combustible Materials
MODELS
W18H/W24H0"0"
W30H/W36H1/4"0"
W42H/W48H/W60H1/4"0"
SUPPLY AIR DUCT
FIRST 3'
CABINET
Clearances Required for Service Access
and Adequate Condenser Airflow
MODELSLEFT SIDERIGHT SIDE
W18H, W24H, W30H, W36H15"20"
W42H, W48H, W60H20"20"
3. Locate and mark lag bolt locations and bottom
mounting bracket location (see Figures 3A – D).
4. Mount bottom mounting bracket.
5. Hook top rain flashing, attached to front - right of
supply flange for shipping, under back bend of top.
6. Position unit in opening and secure with fasteners
sufficient for the application such as 5/16" lag/
anchor/carriage bolts; use 7/8" diameter flat washers
on the bolts.
7. Secure rain flashing to wall and caulk across entire
length of top (see Figures 3A – D).
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 if combustible wall.
9. On side-by-side installations, maintain a minimum
of 20" clearance on right side to allow access to
control panel and heat strips, and to allow proper
airflow to the outdoor coil. Additional clearance
may be required to meet local or national codes.
WARNING
Failure to provide the 1/4" clearance between
the supply duct and a combustible surface
for the rst 3' of duct can result in re causing
damage, injury or death.
Manual 2100-654C
Page 6 of 34
NOTE: Refer to Figures 2 – 7 for dimensions and various mounting configurations.
FIGURE 2
Dimensions of Basic Unit for Architectural and Installation Requirements (Nominal)