According to my files, the standard analog Dometic thermostat is wired as follows:
Fan..........Orange or Tan
Cool.........Yellow
Ground......Black or Green
Furnace.....White
High Fan....Blue
+7.5vdc.....Red
This thermostat looks like this:
I am not sure where the Red gets its 7.5vdc. I would look at the furnace first to see if it's there. If not, it will be in the A/C. According to my install manuals, both the furnace and the A/C are capable of providing the operating voltage for the thermostat.
Important note: IF YOUR UNIT HAS ONE OF THE NEW DOMETIC DIGITAL THERMOSTATS, DISREGARD THE ABOVE INFO. The new Dometic digital control system uses a proprietary signalling system between the thermostat and the appliances. It's uses a cable similar to a phone or computer data cable and it's NOT tapable in the way that we've all worked with the analog thermostats for so many years.
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