Dometic HeatPump Constant Run

[HammerGeek]

Sometime in the night, our front Dometic HeatPump decided to declare independence from the rest of the RV. It is not communicating with the thermostat (Micro-Air Easy Touch 357) and is running constantly in heat in what I think is slow fan mode. I don't know for sure, but it does not appear to be Max heat. I think if it was running in Max heat we would be burning up by now. The air coming out of the register is warm, just not sure it is as warm as normal. But that is a guess.
The only way I can get it to shut off is to open (turn off) the breaker. When I shut (turn on) the breaker, it comes back on.
The rear Dometic HeatPump is operating as normal using the same thermostat.
My first thought is that there is a communication or 12vdc problem that is preventing communication between the control board and the thermostat.
Any thoughts or troubleshooting tips?

[HammerGeek]

Well....I can't believe it was this simple. I'm a computer guy and the "ON/OFF" test is always one of the first things we try. I had turned the breakers off and back on but that didn't fix it. I didn't want to take the thermostat off the wall because it was difficult and I was afraid I might break it. Well..I got it off (without breaking it), unplugged it and plugged it back in. Shazam! It works now.

[wamcneil]

Glad you got it working.
Sounds like it was a sketchy contact in the data cable?
Turning off the breaker only interrupts power to the compressor and fan. The rest of the unit is 12v.
There's also a button sequence to restart the thermostat that's worth a try in cases like that.
Cheers,
Walter