As I mentioned in another post, when it is below freezing, I turn the Artic Pac on, fridge and water heater on, set the thermostats to 40 (assuming I am not in it) and have not had a problem. I was in Las Vegas Monday nite and it got down to 19.
Remember, it is the rear furnace which is ducted into the compartments, so be sure it is on, not just the front. I agree, the fireplace keeps things warm until it gets real cold, then the furnaces come on. They are very fuel efficient. I don't leave the fireplace on when I go to bed or when we are not in the mh.
Happy Trails, Forrest
(Forrest and Donna)
2011 Georgetown 378TS
2011 Ford Escape V-6 4X4