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Brokezitnow's avatar
Brokezitnow
Explorer
Aug 11, 2022

wiring a coleman thermostat

Any help would be appreciated. I had an Atwood thermostat in a 2003 jayco designer camper.
The atwood thermostat has died.
I bought a Coleman mach thermostat For now i want to hook up the Mach thermostat for air conditioning
The old thermostat had 7 wires coming out of the wall.
3 wires came from the furnace as follows:
1 red supplying 12 v current{a smaller diameter wire}
1 white {common}
1 white larger wire

There is another bundle enclosed in a gray sheath. They are small diameter thermostat wires
1 red {power}
1 blue{compressor)
1 green (fan)
1 white (common)

The new thermostat has the following:
B(12volt-)Blue
R(12 volt+)Red
Y(Cooling)Yellow
W(heat)
GH(High fan) Green
GL(Low fan)Gray)

What wire do I hook together to be able to use the air conditioner?