few years ago i towed my trailer up in the woods a few days early to hunt season, and went home. Didn't notice i had nudged the themostat, and i really don't use the heater, so didn't pay attention. Till i went back up and found i had no battery from the fan running.
in the 20 years i have had the trailer, used the heater maybe twice.
running a couple of burners on the stove, or one of those little coleman portable heaters for a few minutes has always worked. I always have a window open, mainly cause i like it, but also because of co concerns.
