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2
NOTE: Wiring schematic for the unit is located in plastic bag
on front of control box door.
SELECT UNIT
For Cooling with Electric Heat units see below. For Heat
Pump units see page 5. For Cooling Only units see page 7.
COOLING WITH ELECTRIC HEAT UNITS
Remove Existing Controls
1. Remove ALL 3 wires (yellow, white and orange) from
the fan cycle switch. See Fig. 6.
2. Remove the following wires from the push button switch:
a. Power cord wire from L1.
b. Yellow compressor wire from COMP.
c. Violet heater wire from HTR.
d. Grey heater wire from LS.
e. Black fan motor wire from HI.
f. Red fan motor wire from LO.
g. Pink L2 wire from L2.
3. Remove the thermostat and push button switch controls
and all remaining attached wires and discard. Remove
thermostat bulb and mounting bracket from front of coil
and discard with the thermostat control. See Fig. 7.
Install New Wall Thermostat Controls
1. Remove knockout on control box cover for thermostat
wiring interface. See Fig. 8.
2. Mount wall thermostat control panel to front control box
cover using 3 of the no. 10 hex head screws provided. See
Fig. 9-11.
NOTE: Be sure removable terminal block on control
board is lined up with hole in control box cover from
knockout in previous step.
3. Re-connect wiring to fan/cycle switch. See Fig. 6.
a. Black Hi Fan speed wire to top terminal on fan/
cycle switch.
b. Red Low Fan speed wire to bottom terminal on
fan/cycle switch.
c. Grey Fan wire (factory installed on printed circuit
board from Relay K3, see Fig. 12) to center termi-
nal on fan/cycle switch.
WIRING SCHEMATIC
STANDARD PTAC MODELS
CONTROL PANEL
COVER PLATE
PUSH BUTTON
SWITCH
THERMOSTAT
KNOB
CONTROL BOX
COVER SCREWS
CONTROL PANEL COVER
PLATE ATTACHMENT SCREWS
TEMPERATURE
LIMITER
PUSH BUTTON SWITCH
ATTACHMENT SCREWS
THERMOSTAT CONTROL
ATTACHMENT SCREWS
Fig. 2 — Removing Front Panel
Fig. 5 — Thermostat Control and
Push Button Switch
Fig. 3 — Control Panel Cover Plate
Fig. 4 — Temperature Limiter