Camper Parked; Freezing Overnight; No One Inside

With furnace on and interior temp at 60 degrees, cupboards open our MH would be okay. Except for the drain pipe running sise to side at the very bottom of the floor with only the metal under skin "insulating" it. If you have a pipe like that put $2 worth of antifreeze down the sink.

Low point drains and the like also tend to freeze up on our rig at -10 C, 15 F. A sock or glove over the valve stops that.