Furnace / thermostat problem

[Lab lover]

2016 FC 26U. No problems after 23 trips the first 2 years. The month after the warranty expired the thermostat stopped working. It appears to turn on and respond to the input buttons-see photo below, and the furnace will quickly bring the temp up to the desired temperature. But as the temp slowly falls over the following hours the furnace doesn't kick back on unless I turn the thermostat off and back on again several times. As this process is repeated, the blower will come on for a minute or so but the furnace doesn't light. If I repeat this turning off/on the furnace will finally come on after the 5th or 6th try. Tanks are full, valves open. Oven and stove work fine. All fuses and switches look fine. "Reset" procedure doesn't change anything. Opened the furnace compartment and blew it out with a compressor-no change. Any suggestions?

Baby it's cold outside!

[OTRA15]

Sorry for your troubles! I would disconnect from shore power, and turn off the 12-volt circuit breaker for the furnace and stat if there are two breakers. There may also be a 12-volt breaker for the A/C and stat control circuit?

Wait 10 seconds and flip all breakers back on, and do the Dometic hard reboot of the stat again per Dometic manual that came with your AS paperwork. Make sure the date and time are set correctly +/-. Plug back in to shore power at any time.

"Dometic stat hard reboot" threads in case there are any new ideas there:

https://www.google.com/search?q=Dome...=airforums.com

Are your batteries fully charged? On shore power what is the battery voltage on your monitor? [should be 13.7 +/-] After unplugging and waiting an hour, what is the battery voltage percentage? [should be 12.7 +/-] Any chance your battery charger/converter is failing?

Are all the other 12-volt functions working correctly?

Good luck,

Peter