How does a heat pump work?

A heat pump consists of four simple components - an evaporator, a compressor, a condenser and an expansion valve.

Just like your domestic fridge working in reverse, the working fluid in the system is converted to gas by evaporation and at the end of the cycle, back to a liquid by compression. The result is an output water temperature of around 35ºC- 45ºC. This is ideal for underfloor heating in a solid floor construction. In this case, for every 1kW of electricity you use to power the system, you get around 4kW out. Heat pumps can achieve a temperature of 60ºC but at a reduced efficiency output of 2.5.

All ground source heat pumps have two parts: a circuit of underground piping outside the house and a heat pump unit inside the house. The outdoor piping system can be installed in either a continuous loop, compact collectors, or in a bore hole – depending on the space available in your garden.

All air source heat pumps have two parts: a heat pump outside the property to extract the free energy, and an indoor unit to provide the hot water.

Watch videos about heat pumps