pointrow - Since it is a rental house just run with extension cords. You will need to put a male and female plug in your furnace so it can be run on extension cord. That way your not back feeding breaker box. Something we did for 3 different houses is run a permanent wire from outside the back porch to the furnace. We put a 110 outlet at the furnace and a 110 plug outside with enough extra wire to be able to pull it out a few feet to plug into a generator. We then wired the furnace to a 110 plug and outlet (which technically may not be 100% electrical code) so if there is an outage we wheel the generator up, plug it in, then go to the furnace and unplug from house wiring to emergency. It's 100% effective at isolating the generator.If you have a furnace with a condensation pump make sure there are provisions for it as well. I would echo the other folks sentiment: NEVER NEVER connect a generator to the wiring without a disconnect.
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How do you hook your generator to your house?
