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AmyCGoose
Jan 24, 2010, 09:09 AM
I am trying to change out an old thermostat to a programmable one. I have the Robertshaw 9520 and I am trying to install a Hunter 44110. Here is what I am working with:
Robertshaw has 7 wires.
C=brown wire= common wire for non-battery systems
R=red wire=24V
Y1=yellow wire=AC compressor
E=black wire=Emergency Heat
G=green wire=Fan
W2=white wire=Heating
B=blue wire=reversing valve
Hunter has 5 terminals.
G=fan=will attach green wire
Y=AC compressor=will attach yellow wire
W=heating=will attach white wire
RC and RH=connected by a jumper=will attach red wire
That leaves me with the brown, common wire which I will tape off, but what do I do with the black, emergency heat wire and the blue reversing valve wire? Can I use the Hunter thermostat or will I have to purchase a different one?

hvac1000
Jan 24, 2010, 09:14 AM
I do not believe the thermostat you bought will work. I believe you need a heat pump stat 2 stage for heat or them setting

AmyCGoose
Jan 24, 2010, 09:56 AM
I do not believe the thermostat you bought will work. I believe you need a heat pump stat 2 stage for heat or em setting

Thanks for your speedy reply!