@Brendan Stratton @Mike Roy Great conversation. Here's my sermon. Heat pumps are 100% better than boilers, furnaces and any other heat source. Why? Well I've personally lived with them as my ONLY heat source for 6 Maine winters and stayed a toasty 70F when it's -25. No, my house isn't a mega-insulted passive-house, it's a 1987 riff on a cape with the original windows and an insulated attic. I have two Fujitsu Halcyons on the first floor of my 1700 sqf house and NO heat source on the second floor and it's always at least 65 upstairs when it's 70 downstairs in the dead of winter. I heat an entire 1200 sqf rental with ONE heat pump and that's worked great for the past 3 winters. I heat a 7 room office with 2 heat pumps. In the rentals, I do install baseboard electric in far away rooms as backup and extra heat if people want to close doors etc. and I prefer to leave legacy heat sources like furnaces in place in case all else fails. Lots of people (ironically, many HVAC and heating 'specialists included) who've never actually tried using them as base load heating will tell you it's not a good idea. For residential contexts, they are wrong. BTUs are BTUs. Solar panels and a clean grid combined with heat pumps is 100% renewable whereas oil gas and propane are destroying our planet at an ever-increasing clip. Plus heat pumps provide AC, dehumidication, air filtration, dust/pollen removal, programability, wifi smart home etc etc. Plus they come with awesome rebates from Efficiency Maine, they can't explode and don't get their fuel from fracking or Middle Eastern monarchies. Two or three heat pumps cost about the same as a boiler, cost less to operate, come with 10 year warranties and provide way more value for residents and planet Earth. Amen.