Peter W. wrote:

We have a small 30A @ 240 VAC emergency generator. When it is in use, we
run it to a 30A double-pole breaker in the panel, shutting off the main
breaker at the same time. That will cover the freezer, refrigerator,
boiler a few lights and other miscellaneous items as needed, without
having to wire or unwire anything. The feed from the generator is 6/3 SJO
cord, and the unit itself is grounded to a properly installed 8' ground
rod. The three times we have had to use it for more than a couple of
hours, it has worked nicely. Usually, we run a single-ended extension cord
to our neighbors for their refrigerator as well.

Yes, we have a much smaller generator. We have only used it once for an
extended outage. It was WONDERFUL to have it, though. We ran extension
cords all through the house, and ran the refrigerator, freezer, cell phone
chargers and the furnace.

Since the events where this has been needed are so rare, having to rewire
the furnace is not a big deal. I'm more worried about the gas valve
thermocouple going out in the middle of the night.

Jon