Now that we finished our summer trip, looking at possible ski trips in the Barth this winter (staying in resort parking lots). Has anybody done any very cold nights in their barth off the grid? Also, at Mt Hood I couldn't get my heater to fire via the batteries. The fan would run but not set off the sail switch enough to turn the gas on. Granted my house batteries are a bit old but even with the generator running it wouldn't fire. At the next place we had electric, she fired right up. Anybody know how much juice is needed or what I should check to see. Fan seemed to be just as loud as when on electric.