We run an electric heater in underbelly. Took wall down so it gets to back of water connects, and have put pieces of insulation in the water connect center. Tonight looks like it will be a rough one. Low in the teens, but winds are blowing 15-30 MPH with gusts up to 40 MPH. The camper does good in just the cold, keeps real warm. But when there is this much wind, you can feel the difference. Since I am taking the wind broadsided, off door side, it gets the cold in around the slide cutouts. Have the furnace set to come on at 70, hasn't kicked on yet. Should be a fun week, 4"-8" snow called for Monday, not to be above freezing until next Saturday, near 0 two nights next week. Guess I will see if the Yeti package works. lol