You've gotten some good ideas.
Battery and inverter: Get a big inverter, sometimes the starting current for
the fan is larger than the inverter. I found this out with my last furnace.
Never really needed it, but I did try my furnace on the inverter, and the
inverter went off, "low battery". Mighta worked with larger 12 volt cables.
Generator: My favorite, to run the furnace. Problem is the gas engine is
noisy, and won't be polite to run after dark or when kids are supposed to be
sleeping. Chain it down, generators disappear during power cuts.
Vented heater: Well, same problem with your gas fireplace. Only heats one
Infared heater: They make gadgets that screw onto a propane bottle. Either
a gas grill bottle, or a campstove size bottle. Lot better than nothing. And
if the NG is off, too, you have some heat that doesn't depend on the gas
company. I've used infared heaters, they do work.
Portable kerosene heater: These do work. Needs a new wick every year, or
every other year.
Christopher A. Young
Do good work.
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