... replaced my hot water heater with a heat pump heater ...
What's a heat pump?
An air conditioner that can reverse itself.
I keep hearing we will all need to buy them to save the world, but I still don't know how the fuck they work.
I read somewhere you have to buy bigger radiators to run on a heat pump, and that's about all I know about them.
Kind of like a refrigerator, but in reverse.