We never had a problem while under way, though were always driving in daytime. At night while camped during colder weather, we would hang a comforter tucked under the cabover bed and let it hang down thereby isolating the driver compartment from the living area. Doing this were able to keep coach warm with a small elec. heater at night and not have to use propane. I think if you were driving in extreme temperatures, this would work to keep the driver compartment warm/cool also.
Ed (N4RWU) & Becky Taylor
Mistie (Walks 4-down)