DrewE wrote:
Have you compared the power usage of the furnace vs. the electric blanket? I would guess that the electric blanket would use more power than the furnace typically. A pair of golf cart batteries generally should easily power the furnace (as needed) for one night and still have a decent charge left in the morning.
Yes I have and just checked the numbers to verify. Furnace demands 10 Amps when running while the blanket/inverter is at 7 Amps. The big unknown is at a given air temp what will be the hourly cycle time of each? Either way once the temps hit freezing not running the furnace is no longer an option due to potential wet bay freezing.
My one Cracker Barrel parking lot overnight boondock with low temps was in the mid to low 50's. With the electric blanket we were very comfortable and didn't need the furnace. If I recall my volt numbers started out at 12.6VDC and woke up with 12.2VDC or so after a 6 hour run time.
Personally if temps dip into the low 40's or 30's I'm giving serious consideration to running the generator (if allowed) with space heaters to supplement the furnace. Below freezing I'm in a campsite with hookups. I prefer a cool bedroom at night but that's just too cold for me.