Originally Posted By: chaosmagnet
Make sure that your furnace doesn’t need more than 300W.

It's a 3kW (3000 watt) inverter. Both of my furnaces are on a single 15A breaker, so there should be ample capacity for the startup surge current of one. For luck, I'm going to test the inverter with a 13A circular saw -- if it can handle that startup current over and over, I should be okay.