Connect portable propane heater to LP tank on board?

Thanks for the wealth of info! Moisture would be a concern given everyone's allergies... And I wouldn't want to take chances with CO.

The coach has a single 12v marine battery, 660 CCA. I don't mind draining it by morning with the furnace, as I can then use the generator and have the chassis battery to get rolling. The only thing left is to figure out where to pile all the extra blankets lol.