Have RV Questions? Ask an RV Mechanic Online.
Take the cover off and give me the part number of your thermostat. And what this is in........thanks!
That is the board number, but not the RV Comfort part number. It may be on the rear. You might try taking this loose from the wall and CAREFULLY pulling the wiring out of the wall to get to the connections. These can be either a plug or just cap splice connectors. See if they all look good. I suspect that this is just a defective thermostat and not a loose connection, but you need to check. Also you might check up in the ceiling connections which you should be able to access once you remove the ceiling grill. If you can get me the part number, that would help. It should start with a 7 or 8 and be 4 numbers and then a letter and then 3 or 4 more numbers. I may be able to identify it from the number and colors of the wiring and plug or if it has loose wiring. That way I could direct you in some tests if you have a 12 VDC test light. All follow ups are included in our fee.
The part number should be on the rear of the whole unit once you remove it from the wall. Attach a photo of the back and wiring if you don't see it. I am attaching a link to one it might be. http://getrvparts.com/coleman-8530a3451-rv-air-conditioner-heat-pump-thermostat/
Then I suspect that the thermostat is defective somehow. You would ask for that part number 8530-348. Hook it up the same way. It should be under warranty and I would ask the dealer you got it from. Perhaps don't take it out yet. They frown on you doing your own repairs!