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STEP #3
WIRE CONNECTIONS
Page 4
If the terminal designations on your old
thermostat do not match those on the
new thermostat,
refer to the chart below,
or the wiring diagrams that follow.
* C may not be used on all systems.
** O/B is used if your system is a Heat Pump.
Wire from the
old thermostat
terminal marked
Function
Install on the
new thermostat
connector marked
G or F
Fan
G
Y1, Y or C
Cooling
Y1
W1, W or H
Heating
W1,O,B
W1,O,B**
Power
Rh, R, M, Vr, A
R
C
O/B
C *
Common
Rev. Valve
Y2
Y2
W2
W2
2nd Stage Cool
2nd Stage Heat
RS+5
RS+5
Remote 5vdc
RS
RS
Remote Sensor Signal
RS G
GND
Remote Sensor Ground
CK1
CK2
Dry Contact Switch 1
Dry Contact Switch 2