5
Terminal Designator Descriptions
SC, S1, S2
– Remote sensor or outdoor sensor
RC, RH
– 24 VAC hot
C
– 24 VAC common
Y1
– 1st stage cool, 1st stage heat for heat pumps
Y2
– Second stage cool for 2-compressor systems. Second stage heat for 2-compressor heat pump systems.
G
– Fan
W1/O/B
– Configurable
W1
– 1st stage heat for non-heat pump systems
O
– Cool active reversing valve
B
– Heat active reversing valve
W2
– 2nd stage heat for 1 compressor heat pump and non-heat pump
AUX
– Humidifier or dehumidifier
Note:
Not all terminals are used in every model.