Propane heat won't stay on

I have a 5th wheel heartland bighorn.
I turn the propane heat on by pointing it at the AC head unit (it then blows through the floor vents). I also have a single slide thermostat on the wall (not sure if that does anything?)
My heat turns on and it's warm. Will heat to temperature (sometimes) sometimes it just turns off and I have to turn it back on. Lately I've been setting the remote temperature to 5° higher than I want it to be bc that was working for a few weeks. I was told to bypass the AC head unit with 2 wires and put the furnace in its own RV thermostat. Kind of looking for step by step directions.. like, where are these wires? (No I'm not doing it myself, my dad is very handy and has replaced parts in my furnace before and knows campers) but we re not sure the details of this one.


Well-known member
The single slide thermostat is most likely for the thermostat controlled "Fantastic Fan" rooftop fan in the kitchen, My Bighorn also has another thermostat and fantastic fan in the bedroom. This fan cuts on when the thermostat is set for a minimum desired warm temperature, and the ambient temperature exceeds that. The fan should run until the low temperature limit is met, then stop the fan and close the roof lid. There is a power switch on the ceiling fan base that can override the fan function on the ceiling unit, but the thermostat operating the roof vent lid should still work. Additionally, on the roof side of the fan there is a rain moisture sensor that will close the lid and shut off the fan if precipitation is sensed.
You didn't indicate how old your Bighorn is, but the intermittent operation of the furnace may indicate that is needs internal dust out cleaning and/or servicing. There are fire and propane safety devices built into the furnace (such as an air flow detecting sail switch) that can get intermittent over the years.
I rarely use the furnace, opting instead for the electric heater built into the fireplace, or other freestanding electric heaters, along with electric blankets. Saves on propane bills since electric is included into the space rent for me.