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Refer to Figure 10 for information concerning side and bottom
supply and return air duct openings.
BAROMETRIC RELIEF / FIXED OUTDOOR AIR
INTAKE DAMPER ASSEMBLY
This damper assembly is shipped inside of the return air
compartment. It serves as a barometric relief damper on units
with economizer or as a fixed outdoor air intake damper on
units less economizer.
On units with bottom return, install the damper assembly over
the opening in the
side return air duct cover. (See Figure 2.)
Remove the adhesive backed label covering this opening
before installing the damper assembly.
On units with side return, install the damper assembly in the
return air ductwork as close to the unit as possible. Cut an
opening 11-1/2" high by 17-1/2" wide in the ductwork to
accommodate the damper device.
Attach the damper assembly into position by drilling six (6)
holes, 9/64" dia. (#26 drill), using the holes in the hood flanges
as a template and secure with the screws provided.
On units less economizer, adjust the damper to the desired air
flow opening by moving the damper bracket (inside of the hood)
to one of the 3 positions provided. Position 1 will allow
approximately 25% recirculated air flow, position 2
approximately 15% and position 3 approximately 10%. A screw
on each side of the hood secures this bracket in place.
CONDENSATE DRAIN
Plumbing must conform to local codes. Use a sealing
compound on male pipe threads. Install a condensate drain line
from the 3/4" female connection on the unit to spill into an open
drain.
NOTE: The condensate drain line MUST be trapped to provide
proper drainage. See Figure 3.
COMPRESSORS
The compressors are mounted on springs which have been
tightened down for shipment only. After the unit is installed,
back out the compressor bolts until the sleeve clears the top
grommet.
FILTERS
2" filters are supplied with each unit. 1" replacement filters may
be used with no modification to the filter racks. Filters must
always be installed ahead of the evaporator coil and must be
kept clean or replaced with same size and type. Dirty filters will
reduce the capacity of the unit and will result in frosted coils or
safety shutdown. Minimum filter area and required sizes are
shown in Table 4.
SERVICE ACCESS
Access to all serviceable components is provided by the
following removable panels:
•
Compressor compartment
•
Burner compartment (Two panels)
•
Blower compartment
•
Main control box
•
Filter compartment
Refer to Figure 10 for location of these access panels.
CAUTION: Make sure that all screws are replaced on the unit
to maintain an air-tight seal.
THERMOSTAT
The room thermostat should be located on an inside wall
approximately 56" above the floor where it will not be subject
to drafts, sun exposure or heat from electrical fixtures or
appliances. Follow manufacturer’s instructions enclosed with
thermostat for general installation procedure. Seven color
coded insulated wires (#18 AWG) should be used to connect
thermostat to unit.
POWER AND CONTROL WIRING
Field wiring to the unit must conform to provisions of the
National Electrical Code, ANSI / NFPA No. 70 (in U.S.A.),
current Canadian Electrical Code C22.1 (in Canada) and/or
local ordinances. The unit must be electrically grounded in
accordance with NEC and CEC (as specified above) and/or
local codes. Voltage tolerances which must be maintained at
the compressor terminals during starting and running
conditions are indicated on the unit Rating Plate and Table 1.
The internal wiring harness furnished with this unit is an integral
part of a UL and C.G.A. design certified unit. Field alteration to
comply with electrical codes should not be required.
A fused disconnect switch should be field provided for the unit.
The switch must be separate from all other circuits. Wire entry
at knockout openings require conduit fittings to comply with
NEC (in U.S.A.), CEC (in Canada) and/or local codes. Refer to
Figure 10 for installation location. If any of the wire supplied
with the unit must be replaced, replacement wire must be of
the type shown on the wiring diagram. Refer to Table 9 for
electrical data.
Electrical line must be sized properly to carry the load. USE
COPPER CONDUCTORS ONLY. Each unit must be wired with
a separate branch circuit fed directly from the meter panel and
properly fused.
CAUTION: When connecting electrical power and control wir-
ing to the unit, waterproof type connectors MUST
BE USED so that water or moisture cannot be
drawn into the unit during normal operation. The
above waterproofing conditions will also apply
when installing a field-supplied disconnect switch.
Refer to Figure 4 for typical field wiring and to the appropriate
unit wiring diagram for control circuit and power wiring
information.
FIG. 2 - BAROMETRIC RELIEF / FIXED OUTDOOR
AIR DAMPER ASSEMBLY
FIG. 3 - RECOMMENDED DRAIN PIPING
It is recommended that, in Canada, the outlet duct be provided
with a removable access panel. It is recommended that this
opening be accessible when the unit is installed in service, and
of a size such that smoke or reflected light may be observed
inside the casing to indicate the presence of leaks in the heat
exchanger. The cover should be attached in a manner ade-
quate to prevent leakage.
530.18-N10Y
4
Unitary Products Group