Honeywell Home T10 Pro Smart Guide D'installation page 7

Conventional systems
Power open Zone valve
R
Power from transformer
Rc
[R+Rc joined by Slider Tab]
W
Valve
C*
24VAC common
NOTE: If the valve uses Y for power close, the thermostat needs to be configured for a radiant heat system
without cooling.
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 and the system uses Y and G, 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.
Series 20 Zone valve
(power open and power closed)
R
Power from transformer
Rc
[R+Rc joined by Slider Tab]
W
Power open valve (usually B)
Y
Power close valve (usually W)
C*
24VAC common
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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