Below tables outlines detail standard wire color codes on Honeywell T87F Thermostat and HVAC.

Wire Color Code Description/Function

Red
Green
Yellow
White
Yellow
Orange
Blue

R
G
Y
W
P
O
B

24VAC Control Power
Fan
Cooling
Heating
Compressor (Heat Pump)
Cooling Aux (reversing valve fail to heat)
Heating Aux (reversing valve fail to cool)



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