BEGINNER’S GUIDE TO

Above: The Grant Aerona3 inverterdriven ASHP achieves Quiet Mark certification as a low-noise heat pump. It also uses the R32 refrigerant, which has a very low global warming potential (GWP) and helps to deliver great efficiency

An air source heat pump (ASHP) is a modern, low-carbon way to heat your home that’s simple and relatively affordable to install versus other types of renewable technology – with potential to deliver savings on household energy bills. A range of factors will contribute to your decision on whether an ASHP will work for you, including the size of the house, insulation levels and the type of emitters you’re using. So, it’s important to do your research before installing an air source heat pump to ensure it will perform effectively for your home and household. This guide will get you started.

What is an air source heat pump?

Powered by electricity, this heating system functions in a similar way to a fridge, but in reverse. In the UK, most ASHPs are air-to-water systems, which is the type we’ll focus on here (the other option is air-to-air).

Air-to-water heat pumps use a fan to extract warmth from the outside air, passing it through a compressor to boost its temperature. This energy is then supplied to a cylinder or thermal store, where it is intelligently distributed to provide space heating and hot water for the home. What makes ASHPs an attractive, efficient option for homeowners is that, for every unit of electricity they use, they can deliver up to four times more heat energy.