Two of the differences between heat pump (Air Conditioning) and furnace heating are
1: Heat pumps do not work well when tempertures drop below a set point, above freezing, (I thiknk 40 degrees)
In fact heat pumps can be damaged if they are started below a cut off temp (around freezing, I do not know the exact temp)
2: Heat pumps do not heat the basement on the Motor home. The Furnace may heat the basement, or parts of it, specifically the parts with water tanks and/or hoses in them. I recall when I was in the desert there were a couple of times I took a shower, it was rather chilly out so the furnace was running and the cold water you usually get when you first turn on the flow... .Was quite warm.