top of page

Air Source Heat Pumps - the basics

Updated: Mar 4

Air source heat pumps are far more environmentally friendly and much cheaper to run than traditional gas boilers, however the initial outlay is higher. They work by transferring heat from the outside to the inside of a building. This is done by utilising a refrigerant system, much like the reverse of the fridge in our kitchen. They rely on a compressor and condenser to absorb heat in one space and release it in another. The system functions as a heat exchanger.

Heat captured outside the home is compressed, condensed and then distributed inside the home using hot water in radiators and under floor heating, and in some cases using hot air. They’re far more efficient than traditional gas boilers, but heat water to a lower temperature, so you may need to adjust heating programmer times and invest in insulation, underfloor heating and/or bigger radiators to maintain the heat that feels right in your home.

Unlike a combination gas boiler, an air source heat pump can’t provide hot water on demand. You’ll need a hot water cylinder to ensure you have hot water ready for showers etc when you need it. If you’re short on space indoors but still considering an air source heat pump, you may find the Sunamp compact thermal storage system of interest.

What are the alternatives to air source heat pumps?

Biomass heating systems, electric heating and solar thermal panels also offer low-carbon alternatives to traditional gas powered central heating. Find out more about them on generating renewable energy at home on Energy Saving Trust website.

Domestic Renewable Heat Incentive (RHI)

The Boiler Upgrade Scheme (BUS) supports the decarbonisation of heat in buildings. It provides upfront capital grants to support the installation of heat pumps and biomass boilers in homes and non-domestic buildings in England and Wales. 

Acting on behalf of property owners, installers can apply for: 

  • £7,500 off the cost and installation of an air source heat pump 

  • £7,500 off the cost and installation of a ground source heat pump, including water source heat pumps 

  • £5,000 off the cost and installation of a biomass boiler 

£450 million of grant funding is available over three years from 2022 to 2025.

For further sources of infomation, please download our Home Energy Directory.


bottom of page