see camper heating and members projects
http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/25966285.cfmMy personal experience , when it gets below zero, it can be a different ball game. Above zero most units can used with some basic mods and common sense.
I have found a non basement camper a lot easier to deal with in cold temps because I can keep things heated if my furnace suffers a malfunction by using a Mr. Buddy portable propane heater.
If you use a basement model camper and the furnace stops working , you'll have no way (unless you make some kind of major modification)to heat the basement using a back up heater.
Something to think about in camper designs.
My furnace actually heats the entire area under my kitchen sink and bathroom sink without having to open cabinet doors, including my dump valves. It's simply heat generated from the box structure of the furnace that radiates throughout the cabinets. All water lines are protected with no mods.
Try to keep interior water lines away from outside walls. Insulate them if need be.
Wrap the dump valve with insulation. Keep a hair dryer handy.
I wrap my change-over valve (regulator) , if that freezes gas flow will stop, it might also crack . If either happens, gas flow stops. Again a hair dryer will thaw a freeze but a cracked regulator has to changed. I carry a spare.
Cassette toilet , like the one used in Northstar campers, can be used with windshield washer fluid so things don't freeze. Cassettes are self contained systems and do not rely on the campers water system . It can be left alone and used that way in an unheated camper.
My personal choice next time round for winter use would be a Northstar. Its a more simple camper to use in the winter.
A simple test to see how tight any camper is......Close everything up and see how easy to open the rear camper door.
Now close the door and turn on the fantastic fan , listen the motor labor , now open the rear door , it should be more difficult to open and you will hear the difference in the fans motor.
Good luck in your decision, Bob