Working like an air conditioning unit in reverse, an Air Source Heat Pump absorbs heat from the outside air. A fan draws the air over a type of heat exchanger called an evaporator, which contains a refrigerant liquid. As the evaporator is warmed by the air being drawn across it, the refrigerant liquid boils and evaporates into a refrigerant gas. This gas is then sucked into a compressor where it is compressed to a high pressure and forced through a small orifice, gaining lots of energy in the form of heat. This heat is then transferred to your central heating system by another heat exchanger called a condenser to heat your hot water, radiators, underfloor or swimming pool. The refrigerant that has been depleted of its heat is then sent back to the evaporator, to start the cycle of absorbing heat from the air all over again.
Heat pumps can be used for cooling however you would need an alternative emitter which can get very costly, we don’t tend to install those systems often due to the associated cost.
