Learning Thermostat with Remote Cell Control

[candlewickproperties]

I just spent a few hours on the phone with NEST, trying to replace a DOMETIC thermostat with a NEST third generation. I want to be able to remotely turn on the AC, and have very reliable wifi. It turn out that the voltage on my system is likely 12v, and NEST requires a minimum of 24 volt. I followed a likely wiring connection scheme from NEST +7.5 (red wire) to Rc, Cool (yellow wire) to Y1, FURnace (White wire) to W1, FAN (Brown wire) to G (NOTE I LEFT HI FAN (Blue wire) taped and disconected, and GND (green wire) to C. When I connected the green wire to C without the NEST connected, it runed on the AC, which I thought was strange. Given the NEST thermostat was not connected (I was just making connections tot he back plate) it made me think I had some other wire in the wrong place. So I am off to check line voltage, and about to call it not compatible. Wondering if anyone else had a recomendation for a learning thermostat I can use for an RV with a remote control app in the google store. Note I could wire in a 24 volt power supply, but that seems like anotehr thermostat would be easier. A similar post can be found here:

https://heartlandowners.org/archive/index.php/t-55058.html

 

[danemayer]

If you have a coach that's 2010 or older, it may have a 12V thermostat that's analog in nature and the conversion might be possible.

If you have a newer coach with the Dometic Single Zone LCD, or the Dometic Comfort Control, I think they use 5V to signal a controller and operate relays. Never heard of anyone successfully changing one out to anything else.