I did not mean we are using a 500 watt heater on battery power. The camper is parked in our driveway and I am running a 500 watt heater from our house electricity. My point was the 1700 BTU output of the electric heater on low easily keeps the camper 30 degrees above freezing. This makes me believe an order of magnitude increase in BTU from the furnace (18,000 BTU) would be plenty.
Definitely will try the camper and garage pod on the Isuzu NRR and see how things sit. The time and effort that have gone into the camper and garage make the truck itself a small part of the build if we did have to switch. It would take less than a day to do a complete switch including the under truck boxes and backup camera system if we were to find a 20 foot flatbed GMC T-7500 (they do exist but always seem to be on the other side of the country).
