Page 12 of 22
507635-05
Issue 2245
Use only copper conductors.
If any of the original unit wiring is replaced, the same size
and type wire must be used.
If 208 Volt is supplied, transformer connection
must be changed
SINGLE PHASE POWER SUPPL
Y
GROUND
LUG
CONTACTOR
FIELD-SUPPLIED FUSED
OR CIRCUIT BREAKER
DISCONNECT
Figure 3. 208 / 230 Line Voltage Wiring
Thermostat
The room thermostat should be located on an inside
wall where it will not be subject to drafts, sun exposure,
or heat from electrical fixtures or appliances. Follow the
manufacturer’s instructions enclosed with the thermostat
for general installation procedure. Color-coded insulated
wires (#18 AWG) should be used to connect the thermostat
to the unit. A minimum of five wires are required for proper
installation.
Duct System
The duct system should be designed and sized according
to the methods in the Air Conditioning Contractors of
America (ACCA) manual that is most appropriate to the
installation application.
A closed return duct system shall be used. This shall not
preclude use of economizers or outdoor fresh air intake. It
is recommended that supply and return duct connections
at the unit be made with flexible joints.
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.
The unit is shipped ready for horizontal flow (side duct
connections) or downflow (bottom duct connections). All
units are equipped with a drain pan overflow switch that is
installed and wired at the factory. Duct attachment screws
are intended to go into the duct panel flanges. Duct to unit
connections must be sealed and weather proofed.
For horizontal duct systems:
1. Remove the duct covers on side of the unit. They can
be discarded.
2. Install the duct system to the unit.
For downflow duct systems:
1. Remove the duct covers on side of the unit. Keep the
screws and the covers as they will be re-installed later.
2.
Remove the downflow duct covers located inside unit.
Remove the four screws securing each cover. Remove
the covers from the unit. They can be discarded.
3. Remove screws located between the supply and
return air openings that attach the blower deck to the
base pan. These screws can interfere with bottom duct
connections or roof curb seals. Discard these screws.
4. Install the duct system to the unit.
5. Re-install the duct covers removed in Step 1.
Filters
Air filters are not supplied with the unit. A field-provided air
filter must always be installed ahead of the evaporator coil
and must be kept clean or replaced. Dirty filters will reduce
the airflow of the unit.
An optional filter rack kit may be purchased separately
for installation inside the unit’s coil compartment. Air filter
sizes are shown in Table 2 for use with filter rack kit.
The filter rack must be installed prior to installation of
the unit in applications where access to the rear panel
is limited.
NOTE:
Unit Model
Filter 1
Filter 2
24,36
14 x 20 x 1
20 x 20 x 1
48,60
20 x 20 x 1
Table 2. Unit Air Filter Sizes - inches
A Photocatalytic Oxidation (PCO) air purification system
is available as a field-installed accessory for this product.
A wiring harness for the installation of this accessory
has been factory installed. If this accessory is going to
be installed, it becomes critical that the system filter be
installed ahead of this unit’s return. Therefore, see the
PCO accessory for filter requirements, plan the installation
of filter ahead of this unit, and
do not use the internal
filter rack described above
.
Condensate Drain
Drain lines should be hand-tightened only. Do not use
tools to tighten fitting into drain.
CAUTION
This package unit is equipped with a 3/4” FPT coupling
for condensate line connection. Plumbing must conform
