DUCTWORK
Ductwork should be designed and sized according to the methods
in Manual Q of the Air Conditioning Contractors of America (ACCA).
A closed return duct system shall be used. This shall not
preclude use of economizers or outdoor fresh air intake. The
supply and return air duct connections at the unit should be
made with flexible joints to minimize noise.
The supply and return air duct systems should be designed for
the CFM and static requirements of the job. They should NOT
be sized to match the dimensions of the duct connections on
the unit.
CAUTION: When fastening ductwork to side duct flanges on
unit, insert screws through duct flanges only. DO
NOT insert screws through casing.
Outdoor ductwork must be insulated and water-
proofed.
Refer to Dimensions and Clearances Figure for information
concerning side and bottom supply and return air duct openings.
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 below.
COMPRESSORS
For units with reciprocating 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 the Physical Data table.
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 Dimensionsand Clearances Figure 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.
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 9 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 the
Electrical Data Table.
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 the Typical Field Wiring Figure and to the appropriate
unit wiring diagram for control circuit and power wiring
information.
FIG. 2 - 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 adequate
to prevent leakage.
530.18-N10Y
4
Unitary Products Group
