Also remember that air-to-air heat pumps are overall less efficient and powerful than air-to-water or geothermal-to-water type heat pumps. Firstly the later ty

Also remember that air-to-air heat pumps are overall less efficient and powerful than air-to-water or geothermal-to-water type heat pumps. Firstly the later typically have a higher power rating. Secondly, if you can lead water around the house and heat via radiators or floor heating you get a much better efficiency.