Air Source Heat Pumps

An air source heat pump is fitted outside your home, usually near an external wall and can be floor or wall mounted. The external fan extracts heat from the air, even in minus degree temperatures, and converts it into heat for your home. This heat can then be used to heat radiators, underfloor heating systems, or warm air convectors and hot water in your home.

An air source heat pump extracts heat from the outside air in the same way that a fridge extracts heat from its inside. It can get heat from the air even when the temperature is as low as -15° C.

A sunny spot is best, as then the pump doesn’t have to work so hard to warm up the air. That said, it can even absorb heat from the air at sub-zero temperatures, so it could still be suitable even if you’ve only got a very small and shady back yard.

How do air source heat pumps work?

Heat from the air is absorbed at low temperature into a fluid. This fluid then passes through a compressor where its temperature is increased, and transfers its higher temperature heat to the heating and hot water circuits of the house. There are two main types of air source heat pump systems.

Air-to-water
An air-to-water system distributes heat via your wet central heating system. Heat pumps work much more efficiently at a lower temperature than a standard boiler system would. This makes them more suitable for underfloor heating systems or larger radiators, which give out heat at lower temperatures over longer periods of time.

Air-to-air
An air-to-air system produces warm air which is circulated by fans to heat your home. They are unlikely to provide you with hot water as well.

What are the benefits of an air source heat pump?

  • They provide a low carbon footprint for your home or office
  • Heat pumps deliver heat at lower temperatures like -20 C compared to conventional oil and gas boilers
  • Hot water can be heated for both immediate use or later use
  • Contribute to the reduction of energy bills
  • They have a long lifespan with proper care they can be operational for up to 20 years
  • Provides cooling in the summer and heating in the winter
  • No fuel storage is needed
  • High Seasonal Energy Efficiency Rating (SEER)