Dometic thermostat has no power and AC/Furance quit.

[Snowplow]

on our 2019 3120rl the bedroom AC works. But the the AC and Furnace on the main level quit working and there is not power. Shows a code of E1 on thermostat, any Ideas?? thanks Snowplow.

[Mikendebbie]

From my thermostat “owners manual sheet” (1 page front and back)…
E1 - loss of communication between CT thermostat and module board. LCD will cycle between E1 and previous mode setting. System will shut down.

I will try to search for an answer because the sheet does not offer a solution.
Found this posted by Rohrman a while back.

Perform system reset…but this is not correct for my (and yours) thermostat..still looking…but here is this.
Make sure the CCC 2 thermostat is in the OFF mode.
Simultaneously press the MODE and ZONE buttons. The LCD will display “IniT” and all available zones.
Release the MODE and ZONE buttons.
Press the ON/OFF button to exit system set up.

[Snowplow]

Thanks, I have been reading on that about wires coming off etc, and the stats are not very good, it did this a couple of times before but always came back on. Now its just showing that code and I don't any info on the AC units or thermstats. Just the furnance. thanks Dale

[Mikendebbie]

Ignore that stuff I posted above. Do a forum search “dometic thermostat reset” and lots of threads come up. I just read one…the fix in that post was “shut down all power and waited 5 minutes. Problem solved”

I think if you read thru the various post you will find the correct reset procedure for future reference.

[Snowplow]

I believe a wire is broken or lose or the stat is bad . I will do more searching tomorrow. thanks for the help

[DQDick]

Don't forget there are two ends to the cord. The other end plugs into the board in the AC unit it'self. I had the AC unit serviced once and they knocked the plug out up there and there was no furnace or air until it got plugged back in.

[Snowplow]

Thanks for all the input on my furnace and A/C not working on the main floor. I found that the ground wire from the thermostat had came out of the connector on top the A/C unit. I removed the cover and the foam cover in the a/c and all the wires are there and I found the wire. The wiring is just tossed in there and not secured, plus it was poorly wire. A ten year good have done a better job. Not impressed with this trailer or the company.