R – 24 VAC hot
C – 24 VAC common
W1/O/B – Configurable
W1 – 1st stage heat for non-heat pump systems
O – cool active reversing valve
B – heat active reversing valve
Y1 – 1st stage cool, 1st stage heat for heat pumps
W2 – 2nd stage heat for 1 compressor heat pump and non-hp, 3rd stage heat for 2 compressor heat
pump systems
Y2 – 2nd stage cool for 2 compressor systems, 2nd stage heat for 2 compressor heat pump systems
G – Fan
W3 – 3rd stage heat for non-hp systems and 1 compressor heat pump systems
Terminal Designator Descriptions
1
ST
Cool
2
ND
Cool
1
ST
Heat
2
ND
Heat
3
RD
Heat
Heat/Cool
Y1,G
YI,Y2,G
W1,G*
W1,W2,G*
W1,W2,W3,G*
Heat Pump (One Compressor)
Y1,G,O
Y1,G,O
Y1,G,B
Y1,W2,G,B
Y1,W2,W3,G,B
Heat Pump (Two Compressors)
Y1,G,O
Y1,Y2,G,O
Y1,G,B
Y1,Y2,G,B
Y1,Y2,W2,G,B
Dual Fuel (One Compressor)
Y1,G,O
Y1,G,O
Y1,G,B
W2
W2,W3
Dual Fuel (Two Compressors)
Y1,G,O
Y1,Y2,G,O
Y1,G,B
Y1,Y2,G,B
W2
Emergency Heat (Heat Pump Only)
N/A
N/A
W2,G
W2,W3,G
N/A
* G not energized when configured as a gas/oil system
The SC5812 thermostat is configurable for all systems . The configuration directly affects the outputs .
Use the output chart to correctly configure and wire the thermostat to your system .
SC5812 Output Chart
