Friedrich RT4 Thermostat User Manual


 
6
Replace the old labels with the enclosed new labels:
Replacing Wiring Labels
Old New Type
F, G G Fan control relay
B B Heat active reversing valve
Y, Y6 Y Cooling control
H, W, 4 W
Heating control
C C Transformer, common side
M, 4, RH, RS, R R Transformer, hot side