[psomers]

OK. I can see I'm dealing with a couple of smart fellows. My little pea brain thinks if you blown air into (heated space) living area and that area was completely sealed, that area would be somewhat pressurized. Yea, I know a lot of leaks but the air would want to leak at point of least resistance. Underneath storage would be at a slight vacuum to me would be least resistance.
Living in Alabama don't know why I even think about it. In the four years of owning this camper and my previous nine campers I rarely use furnace. We go to Gulf Shores right after Christmas for two months and electric space heater is more than enough.