But do go on about how I don't know enough.
Modern heat pumps do fine well below 0 degrees Celsius. Here's one that's great to -15 C and okay down to -25 C[0]. If you search cold-climate heat pumps, you'll find plenty of information about how modern heat pumps are fine in most the temperatures you'll find in most of the US (including up north).
(I have heard that a lot of them are still only available in Europe, but you can definitely find some in the US.)
"Below 0° Fahrenheit, heat pumps can still heat your home with more than twice the efficiency of gas heating or standard electric heating (such as electric furnaces and baseboard heaters). They’ve been tested and approved as far north as the Arctic Circle, and are popular options in very cold countries like Finland and Norway."
Finland has over 60% heat pumps.
And heat pumps, just to be clear, work by generating a temp difference. The main problem is the efficiency and that drops also because there is a heating cycle needed for the air intake.
How many models did you actually research yourself?
So his point still stands.
That's basically explaining that you did zero basic research.
And I'm not a kid fyi.
Learn to Google and learn to do research
My whole new housing estate have heat pumps.
And I told you before already about Finland. And if you don't know what Finland is: it's a cold country in Europe.
Why do you even respond if you don't know enough about heat pumps?