There are eight factors that you'll need to consider before purchasing your heat pump for home heating. However, we can simplify these factors into one general rule of thumb.
For instance, you'll need to install one tone air condition capacity for every 500ft. to 600ft. of the conditioned floor. Most heat pump sizes are determined by BTUs (British Thermal Units), and one ton equals 12.000 BTU/h or 3.5 kW.
Thus, if you have a 1000 sq. ft. home, then you'll need a 30000 BTU/h heat pump, a 2.5-ton heat pump, or an 8.79 kW heat pump. You could get the 7.6-11KW Energy Efficient Air Source Heat Pump
for House Heating and Cooling with a 220V to 240V Power supply.