I finally tested my heat pump's real efficiency after 3 winters of doubt

I kept hearing heat pumps were the future but mine struggled every January. Last month I strapped a power meter to the unit in my Minneapolis garage and tracked it for 14 days straight. The numbers surprised me, it pulled 3.2 kWh of heat for every 1 kWh of electricity even at 10 degrees outside. That's way better than the gas furnace in my old place which basically turned every dollar into warm air and a big bill. My skepticism came from a 2018 installer who swore I needed backup resistance coils, and I paid $800 for them and never once needed them. I also checked the defrost cycle logs, it only ran 4 times during that whole stretch. If you're on the fence about swapping your furnace, what data convinced you one way or the other?

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alexbennett21d ago

...so what was the actual balance point you hit with it? I've got a similar setup here in Maine and my unit starts struggling below 15 degrees no matter what the marketing says. The 3.2 COP at 10 degrees is solid, but I'm wondering how much of that is because your garage is insulated and sealed versus a typical drafty setup. My bigger question though is this: did you factor in the defrost cycles eating into that COP when you did the math, because those little bastards suck down power like crazy even if they only ran 4 times total. I tracked mine once and each defrost cost me about 1.5 kWh just to melt ice, which basically nukes any savings on a cold week.