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Author Topic: AC thermostat wires  (Read 203 times)


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AC thermostat wires
« on: July 03, 2017, 02:40:26 PM »
I am changing from a Dometic ac to a Coleman ac. The Coleman has 4 wires to thermostat, while the Dometic has 2. Has anybody
had to add 2 wires to thermostat before?

Gary RV_Wizard

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Re: AC thermostat wires
« Reply #1 on: July 03, 2017, 03:17:37 PM »
Well, you can't just "add wires" somewhere on a thermostat - they have to connect to the expected function/terminal. You may need a different thermostat, or maybe those extra wires are for a function you don't care about, e.g. hi/Lo fan speed or whatever. What do the instructions say about each wire?

Is it practical to pull a new 4-conductor cable if really needed? Often that is near impossible in an RV.
Gary Brinck
Summers: Black Mountain, NC
Home: Ocala National Forest, FL


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Re: AC thermostat wires
« Reply #2 on: July 03, 2017, 03:35:06 PM »
Does one of the thermostats run on a battery by any chance??  Normally you need at least a minimum of  4 wires as an RV thermostat requires battery (12V) and ground as well as the air conditioner controls. Double check you have the correct thermostat supplied for your expected use.

Once again, makes and models information will help us to help you.
« Last Edit: July 03, 2017, 03:37:29 PM by Alfa38User »
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