We are snowbird ing in reverse, went from Central FLA, to PA. Made it in before the snow! I was under the false impression, that I needed 110v to run the furnace, (I have had experience with AC and reverse cycle AC for heat). Well, I left the thermostat set on furnace, and 50 degrees, when we left. When we got to our first stop in the 30's, but it was nice and warm inside! We have left it set that way for the entire trip, and it is nice to come into a nice warm RV after setting up in the evening! As stated make sure registers and such are not covered, and you will be OK!