Instructions / Assembly

Page 11 of 19
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
Thermostat
The room thermostat should be located on an inside
wall where it will not be subject to drafts, sun exposure,
manufacturer’s instructions enclosed with the thermostat
for general installation procedure. Color-coded insulated
wires (#18 AWG) should be used to connect the thermostat
installation.
Figure 4. Typical Wiring Connections
R
G
W
O
Y1
C
R
G
W
O
Y1
C
THERMOSTAT OUTDOOR UNIT
Red
Blue
Yellow
Orange
White
Green
*
!
CAUTION
required by the indoor thermostat. Refer to the
thermostat installation instructions.
Do not connect connections except when
C
*
“O” connection used only on heat pump models
SINGLE PHASE
L2
L1
GROUND
SCREW
POWER WIRING
208/230-1-60
(75° MIN. WIRE)
POWER WIRING
24V CONTROL WIRING
(NEC CLASS 2)
W1, W2 can be used to stage electric heat accessory on 10,
15 & 20 kW models. 5 And 7 kW heater accessory function
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.
installed and wired at the factory. Duct attachment screws
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.
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 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
the unit in applications where access to the rear panel
is limited.
NOTE:
Table 2. Unit Air Filter Sizes - inches
Unit Model Filter 1 Filter 2
24,30,36 14 x 20 x 1
20 x 20 x 1
42,48,60 20 x 20 x 1
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