Ha, we have a 2014 coach. Several years back I thought I had a problem that the propane was not supposed to run when I had the electric/heat pump selected. Turned out that the propane will run if there is a big enough gap between the selected temp on the thermostat and the actual temperature that the unit is at( I forget what the difference is). Makes sense, heat pumps will only work well when outside is about 32 degrees or greater. The thermostat is smart enough to know when to kick in the propane to assist the electric heat so the coach doesn't freeze up. As the coach comes up close to the set temperature you should see the propane then kick out and if the heat pump will has enough BTU's it will then sustain things on electric only. I was all set to replace the thermostat until one of the then senior members explained this to me. Good Luck...