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4. 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. 20) to center termi-
nal on fan/cycle switch.
4. Re-connect the following wires to control board. See
Fig. 20.
a. Violet heater wire to Heat2 on relay K2A1.
NOTE: The male piggy back terminal is not used. This
terminal may either be removed or pinched back to fit the
connector onto Heat2 relay terminal.
b. Pink L2 wire to L2 (brass post terminal) on relay
K2Al.
c. Power Cord wire (Ll) to L1 (brass post terminal)
on relay K2.
d. One of the 2 black reversing valve wires to RVS
(no polarity).
e. Remaining black reversing valve wire to L2 (brass
post terminal) on relay K2A1.
NOTE: Black reversing valve wires are molded together
in a 2-wire bundle.
5. Connect the following wires from the control board to the
Outdoor Frost Control (OFT):
a. Red wire from Heat1 on relay K2 to terminal 2 of
OFT.
b. Yellow wire from COMP of relay K1 (with piggy
back male terminal) to yellow wire already
attached to terminal 3 of OFT. Attach both wires
back on to terminal 3 of OFT.
6. Secure control board ground wire (green) to ground
screw on control box door with power cord and chassis
ground wires. See Fig. 13.
7. Remove coil filter. Install Indoor Coil Freeze Thermostat
(IFT) into coil.
a. Use a pen to make an opening in the fins 4-in. from
the right side of the coil between the second and third
tube from the top to install freeze sensor (Fig. 14).
b. Push freeze sensor into opening made in Step 7a.
c. Bend clip on scored line and install in fins (the curved
notches will lock clip in place) next to sensor to hold
sensor in place in the coil. See Fig. 15.
8. Replace filter (indoor coil freeze thermostat will be locat-
ed in the coil behind the filter).
9. Dress wires using wire ties provided.
10. Close the control box door and secure by re-attaching
screws saved earlier. See Fig. 3.
11. Reinstall plastic control panel cover using the 2 screws
removed earlier. See Fig. 3.
Install Labels and Schematics
1. Remove old wiring schematic label and install new wir-
ing schematic label in same location. See Fig. 16.
2. Install conversion label to front of control box. See
Fig. 16.
3. Install Hi Speed/Low Speed label next to fan cycle switch
on side of control box. See Fig. 17.
NOTE: Fan cycle switch now becomes a speed selector
switch and selects whether the fan runs in high speed or
low speed. It is recommended to set the switch to low fan
speed for maximum sound comfort.
Fig. 19 — Cut Blue Wire from Terminal 1
PINK (L2 ON K2A1)
VIOLET (HEAT2 ON K2A1)
PLAIN POWER CORD
(L1 ON K2)
RED WIRE
(HEAT1 ON K2)
YELLOW WIRE
(COMP ON K1)
GREY FAN WIRE
BLACK WIRE FROM
REVERSING VALVE
TO RVS
(NO POLARITY)
BLACK WIRE FROM REVERSING
VALVE TO L2 ON K2A1
(NO POLARITY)
K1
K2
K2A1
Fig. 20 — Typical Wall Thermostat Interface Board Terminal Connections (Heat Pump Control Board Shown)