Honeywell Home T10 Pro Smart Guide D'installation page 6

Wiring
NOTES:
1. Use 18- to 22- gauge thermostat wire. Shielded cable is not required.
2. Set the R Slider Tab on the UWP to the up position (1 wire) for 1 transformer
systems or the down position (2 wires) for 2 transformer systems. See "Setting
Slider Tabs" on page 4.
3. Set the U Slider Tab as shown in the diagrams on page 4.
Conventional systems
1H/1C System (1 transformer)
R
Power
Rc
[R+Rc joined by Slider Tab]
Y
Compressor contactor
C*
24VAC common
W
Heat relay
G
Fan relay
1H/1C System (2 transformers)
R
Power (heating transformer)
Rc
Power (cooling transformer)
Y
Compressor contactor
C*
24 VAC common from cooling transformer
W
Heat relay
G
Fan relay
2H/2C System (1 transformer)
R
Power
Rc
[R+Rc joined by Slider Tab]
Y
Compressor contactor (stage 1)
C*
24VAC common
W
Heat relay (stage 1)
G
Fan relay
W2 Heat relay (stage 2)
Y2
Compressor contactor (stage 2)
* 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.
Heat-only System with Fan
R
Power
Rc
[R+Rc joined by Slider Tab]
C*
24VAC common
W
Heat relay
G
Fan relay
Cool-only System with Fan
R
Power
Rc
[R+Rc joined by Slider Tab]
Y
Compressor contactor
C*
24VAC common
G
Fan relay
Hot Water Relay Panel
R
Power
Rc
[R+Rc joined by Slider Tab]
W
Heat Relay
C*
24VAC common
NOTE: If the panel does not provide 24 volts AC
at R and C, set the slider to down position and
wire a separate transformer to Rc and C.
6