Ok so it has been nearly 20yrs since I've 'winter camped'.
- Single type #27 battery, (I don't recall if I had solar or truck-2-camper charging at that point or not)
- Temps in 20-30's, furnace was mostly on most of the time
- I had not winterized, no water system issues
- Admittedly after spending the night in the snow the next day I left for lower elevation (and less snow)
- Given that 1 day/night of running the furnace and 2000 era lighting would of used up my single battery, I must of had someway of charging the battery
Over the years I hear that most folks just drain their water (blow out excess with air on the city water intake), flush toilet with RV antifreeze and if staying more than 1 day/night have someway to charge the battery (for furnace+lighting) or have more than a single #27 battery (100Ah).
While it seems (and IS) counter productive, cracking the roof hatches and having a window cracked for ventilation to combat condensation is needed. (otherwise you'll find moisture on the windows and on/in the walls)
- Mark0.