Help!

[StanlieS]

I replaced this Dometic 13 k btu AC with a Furrion Chill-cube unit. Since the old T stat worked both furnace and AC via control in the AC unit my T stat shows an error E1 and heat will not work. I purchased a new two wire T stat but the wiring from old config is a three wire (+)(-)12vdc and a return to old AC. Then there was a two wire to furnace. The wire going to furnace is reading 12 vdc now. Does anyone know how to connect the propane furnace to work off of new T stat?

 

[TheLooks]

It is a bit more complex then that. I would guess you had the Dometic CT which operates by digital signal not voltage. The one wire you mention is the communication wire. If you retained the old control box in the old AC, it should work. The control box is what communicates with the thermostat and turns things on and off. The AC unit is "dumb" it just does what the control box tells it. E-1 is a loss of communication. That one wire in the middle is not hooked up right. It does not have voltage on it. I believe that error code is common on other Dometic thermostats as well.

 

[TheLooks]

Pictures please of the thermostat.

 

[StanlieS]

Update: After tracing the wiring out from the old AC to T stat and wiring from Furnace I decided just to jump 2 wire low voltage cable going to furnace and it turned furnace on and off. Rewired these to new two wire T stat and I’m up and running. Old AC controls must have had a relay output that controlled furnace depending on the mode of the old T stat. Happy Camper!

 

[TheLooks]

Yes, that is why the control box must match the thermostat. But it is simply a loop that and old fashioned thermostat will work like a switch....good job.