An air source heat pump is a type of heat pump that uses the outside air as a heat source or heat sink to heat or cool an interior space.

An air source heat pump (ASHP) is a system which transfers heat from outside to inside a building, or vice versa. Under the principles of vapor compression refrigeration, an ASHP uses a refrigerant system involving a compressor and a condenser to absorb heat at one place and release it at another.