Our aspen trail furnace runs on propane and has a heater duct that warms the underbelly. If you use an electric heater along with the propane furnace to heat the interior. The propane furnace will not run as much, cutting back on heating the underbelly.
I was told by the seller that it could tolerate temps in the high twenties at night as long as the daytime temperatures get above freezing..
Be sure to drain your city water connection hose so that you don't end up with a hose full of frozen water in the morning.
Pat & Barb
2019 5.3L ECOTEC3 V8 Chevy Silverado 1500
2016 Aspen Trail 1900RB