Barn conversion with Mitsubishi Ecodan air source heat pump

Air source heat pumps: a buyer’s guide

Find out whether your home is suitable for an ASHP with this comprehensive guide

By Hugh Metcalf | 1 September 2020

Learn more about how air source heat pumps work, the running and installation costs and whether this renewable heat source is the right choice for your home.

You may be considering changing a gas boiler heating system for an air source heat pump. These low-carbon heating systems are estimated to help lower your home’s carbon footprint by up to 50 per cent.

air source heat pump outside of modern home - green homes grant - grand designs

Photo: Viessman’s Vitocal 300a air source heat pump offers a modern aesthetic for style-conscious homes

How do air source heat pumps work?

Grand Designs’ own Kevin McCloud once described the air source heat pump as a ‘reverse fridge’, which offers a frame of reference for how an air source heat pump operates.

Heat is absorbed from the outdoor air at a lower temperature into a fluid, before being compressed to raise its temperature. This higher temperature heat can then be passed to the hot water and heating of your home.

Air source heat pumps can be one of two varieties: air-to-water heat pumps are the most common in the UK, transferring the heat into water which can then be used for traditional home heating elements; while air-to-air heat pumps work with a circulation system to heat the air itself. The latter is not included in the Renewable Heat Incentive scheme.

how an air source heat pump works

Image: Adobe Stock