Understanding Air Source Heat Pumps

The technology behind heat pumps is not new but is based on that of the refrigerator – yes the one you find in your home kitchen.

Air source heat pumps - how they work

"Heat Pumps take up to 78% of the heating energy from the ambient air."

Air source heat pumps work by absorbing heat from the outside air at low temperature into a fluid (a liquid refrigerant), then passing it through a compressor to increase its temperature. The fluid is then transferred to the heating and hot water circuits of the house. The principle works even in the middle of winter at temperatures as low as -15ºC.

Heat pumps work much more efficiently at lower temperatures than a standard boiler system meaning they are more suitable for under-floor heating systems and use with larger or fan assisted radiators, which give out heat at lower temperatures over longer periods of time.
How Air Source Heat Pumps work
  1. Energy from the outside air is transferred to the liquid refrigerant and circulated through the evaporator.
  2. The heated refrigerant gas is then compressed to reduce its volume but increases its temperature.
  3. The compressed gas enters the condenser surrounded by water from the heating system, where it gives up its heat.
  4. The cooler liquid refrigerant then passes through the expansion valve which reduces the pressure.
Air Source Heat Pumps can work in conjunction with a Solar Thermal system.
Energy consumption and potential savings
  • Your heat distribution system
  • Your fuel costs 
  • Your old heating system
  • Water heating
  • Using the controls
Energy consumption
More than 80% of the energy used at home is for heating and hot water production.

Air Source Heat Pumps energy savings