I guess I was trying to say its efficiency breaks down and isn't competitive with basic electric baseboard heat at some temperature below zero celcius (not sure what the break-even point is). I didn't think people in Alaska would be using that for home heating, is that a thing? The norm here is gas heat and the odd electric baseboard home which broken down elsewhere by another commenter is approximately 10x the price of gas heating.

> I guess I was trying to say its efficiency breaks down and isn't competitive with basic electric baseboard heat at some temperature below zero celcius (not sure what the break-even point is).

At the 'break down point' an air source heat pump (HP) is no worse than a baseboard heater: in both cases the COP is basically 1.0. So you might as well go with the HP as it'll be more efficient for probably the majority of the year.

You can get gas furnaces that are 'dual fuel': they'll run the HP refrigerant through the exchange and circulate the conditioned air, and once it's "too cold" switch to gas.

If you're going to buy a only-cooling AC unit, then spending a little more on a heat-cool HP is probably a smart idea. There's a payback period, and it depends on the price of your electricity and fossil fuel (NG, propane).

And apparently Fujitsu's work better in F but the same in C. I always thought these were display-only settings.