Honeywell pro Series Professional Install Manual page 7

Heat pumps systems
1H/1C Heat Pump System
R Power
Rc [R+Rc joined by Slider Tab]
Y Compressor contactor
C* 24VAC common
O/B Changeover valve
G Fan relay
2H/1C Heat Pump System
R Power
Rc [R+Rc joined by Slider Tab]
Y Compressor contactor
C* 24VAC common
O/B Changeover valve
G
Fan relay
Aux Auxiliary heat**
E
Emergency heat relay**
L
Heat pump fault input
NOTE: Do NOT use W for heat pump applications. Auxiliary heat must wire to AUX or E.
* This thermostat requires a C-Wire. If a C-Wire is not available, use C-Wire adapter accessory
THP9045A1098.
** If you do not have separate wires for the Aux and E terminals, connect the wire to the Aux terminal.
2H/2C Heat Pump System
R
Power
Rc
[R+Rc joined by Slider Tab]
Y
Compressor contactor (stage 1)
C*
24VAC common
O/B Changeover valve
G
Fan relay
Y2
Compressor contactor (stage 2)
L
Heat pump fault input
3H/2C Heat Pump System
R Power
Rc [R+Rc joined by Slider Tab]
Y Compressor contactor (stage 1)
C* 24VAC common
O/B Changeover valve
G Fan relay
Aux Auxiliary heat**
E
Emergency heat relay**
Y2
Compressor contactor (stage 2)
L
Heat pump fault input
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