I have insulated my waterlines with tube foam and insulated the water heater and battery compartments which helps. Winter camping means keeping propane tanks filled and the batteries charged to keep the furnace running. No generator but we have a 4 gauge wire from the alternator to the house batteries so we can run the truck to recharge. Also, while the truck is running, we crank up the heat and blow heat into the tc through the window tunnel so we charge and heat at the same time. TC furnace is usually set to 60 and we leave certain cabinet and access doors open for heat to circulate in those areas. Never had a problem. Just have to keep on top of battery charging
