This year I put together a furnace power outage kit, consisting of a 120V three prong pigtail, a 1000W inverter, some wire nuts and some 12VDC battery cables.

If we lose power but the natural gas service stays on (easily tested at the stove) I can easily turn off the circuit breaker to the furnace, use my multimeter to make sure the wires are cold, and attach the furnace directly to the pigtail.

We then have a number of options, including a gas generator outside with an extension cord, a Very Large Powerbank (freshly charged), or taking a battery out of one of the cars to bring in to run with the inverter. In that case, when that battery gets low, we can reinstall it in the car and run the car to recharge it.

Perhaps this summer I’ll pay an electrician to install a generator transfer switch.

Important notes: At no point will I make or possess a “suicide cord.” And the furnace will be completely disconnected from the house wiring while the pigtail is attached.