What are they?
Air source heat pumps absorb heat from outside air. This can then be used to heat radiators, underfloor heating systems, or warm air convectors and hot water in the home.
An air source heat pump extracted heat from outside air in the same way that a fridge extracts heat from its inside. Even when the temperature is as low as -15° C heat can be extracted.
Although heat pumps have some impact on the environment as they need electricity to run, the heat they extract from the ground, air, or water is constantly being renewed naturally.
How they work - the video