Dometic thermostat E1 error

[craig2fly]

The thermostat shows the E1 error, the fan, ac and the furnace won’t work. The power, fuses and circuit breakers all seem to be ok. Does anyone know what the problem may be? This is a 2013 Thor Palazzo

[The Gritz Carlton]

You have two identical post going here on this same issue...be sure to check both of them. Remove rooftop shroud and check all wiring terminations...especially the green ground wire. Remove wires and clean contact surfaces.

[Peterrrr]

Loss of communication between the thermostat and module board. Here is the manual for your thermostat.

[The Gritz Carlton]

I read all that too Peterrr...lots of chatter going on. Another guy had same issue and tracked it down to deteriorated exterior wiring.

[craig2fly]

The furnace and roof ac unit are 2 separate units controlled by one Dometic thermostat. Where is the module board located that controls both of these units on a 2013 Thor Palazzo? There are only 3 wires at the thermostat ,red-white-green. Just started using this forum, any help is appreciated.

[TurnerFam]

I would also try a simple measure/test to start: simply switch 'off' your 12v switch at the entry door, for a moment, then back 'on'. Sometimes, like computers, a reboot is a simple solution.

[16ACE27]

Originally Posted by craig2fly

The furnace and roof ac unit are 2 separate units controlled by one Dometic thermostat. Where is the module board located that controls both of these units on a 2013 Thor Palazzo? There are only 3 wires at the thermostat ,red-white-green. Just started using this forum, any help is appreciated.

I've never seen an RV thermostat with only 3 wires attached, even the battery powered ones.

Check out this thread:

http://www.thorforums.com/forums/f4/...rade-2100.html

[Peterrrr]

I am assuming your Palazzo has the Dometic Single Zone TStat (similar to the two that my 2014 had, because the model I had, had two furnaces). I am also assuming you checked the 12v fuse for appliances, but they should be good as you have a display on the Tstat. There are only 3 wires from that Tstat, DC pos, DC neg, and comms. They run to the control box accessible after removing the air return cover of the Air Conditioner. The furnace DC wires run up there also. The furnace DC neg could be spliced into the Tstat DC neg before the Tstat wires run into the control box. There could also be a connector before the control box. Try wiggling the wires going into the connector(if present) or into the control box. Could be corrosion as a result of moisture. Good luck.