
7
Step 5. Label the Wires with Tags
Carefully disconnect and label the wires from your old themostat one wire at a
time, using the label (label 1 )provided.
Step 4. Take a photo
Take a picture of the wires connected to the terminal of your old thermostat. You
may need to reference this photo later on.
Terminal designation:
Terminals What it means
RC 24VAC primary for cooling
RH 24VAC primary for heating
W1 1st stage Primary heating relay / Aux heat
W2 2nd stage Secondary heating relay / Aux heat
Y1 1st stage Primary cooling compressor contactor
Y2 2nd stage Secondary cooling compressor contactor
GFan relay
C24VAC common*
O/B Changeover valve for heat pumps
SWiring Module Connection
*Multiple use reserved, including but not limited to: emergency heat
line, humidifier control