Terminal Cross Reference
Old
Sensi
Heat Pump
thermostat… thermostat…
RC
RC*
Power for cooling
RH, R
RH*
Power for heating
C, X, B**
C
Common wire
W, W1, W/E,
W/E
1st stage aux/
Aux/E, E
emergency heat
W2***
W2
2nd stage aux/
emergency heat
Y, Y1
Y
1st stage compressor
Y2
Y2
2nd stage compressor
G
G Fan
O, B**, O/B
O/B
Heat pump
changeover valve
L
L
Heat pump diagnostic
* If the old thermostat has separate RC and RH wires, clip the RC/RH jumper
on the back of the thermostat.
** Label “B” as “C” only if the old thermostat also had a wire on “O”.
If there is no wire on “O” – label the wire “B”.
*** On Heat Pump systems with separate W2 and E wires, label both wires W/E
(2 wires on one terminal).
For Heat Pump Systems
