An air source heat pump is a renewable energy system that heats your home by extracting free warmth from the outside air, even on cold winter days, down to -25°C. It works just like a fridge in reverse, moving heat from the air outside into your radiators and hot water cylinder.

By replacing traditional gas or oil boilers, air source heat pumps help UK homes switch to low-carbon, sustainable heating. Because they don’t rely on burning fuel, they’re considered renewable and play a growing role in the UK’s move toward net zero

Unlike gas or oil boilers that create heat by burning fuel (combustion), air source heat pumps use electricity to transfer existing heat from outside air into your home (heat transfer). This process is highly efficient, with typical heat pumps providing 3-5 units of heat for every 1 unit of electricity used, far outperforming most modern boilers. Heat pumps operate at lower flow temperatures, delivering a gentle, steady warmth through radiators or underfloor heating for all-day comfort. The journey is simple: outside air passes through an evaporator, where R290 refrigerant absorbs its heat and is then compressed, releasing that heat into your home via a condenser, before cycling back through an expansion valve ready to start again.

Yes, air source heat pumps are among the most efficient ways to heat a UK home. Their Coefficient of Performance (COP) measures how much heat they generate from each unit of electricity, typically 3-5 times more than they consume. Seasonal performance (SCOP) remains impressive throughout the year. Good home insulation maximises this efficiency, ensuring you get the best value from your system. Compared to old electric heaters or boilers, heat pumps use less energy overall, lowering both bills and emissions.

Most UK homes can accommodate an air source heat pump, but suitability depends on more than just available space. As covered above, insulation levels and plumbing infrastructure both play a role in how efficiently the system will run, and we will assess both as part of your survey.

Beyond that, you will need:

• A small outdoor space for the unit, roughly the size of a washing machine, with reasonable airflow around it
• A dedicated indoor spot for a hot water cylinder

Once everything is in place, the system runs quietly and reliably at around 35 to 47 dB, no louder than a quiet conversation. Our survey process is designed to identify everything your home needs upfront, so there are no surprises once installation begins.

Yes. InstaGen air source heat pumps are designed for the UK climate and operate efficiently even at sub-zero temperatures (down to -25°C).

No. Most modern air source heat pump systems, including the InstaGen Heat Pump, are quieter than a typical gas boiler; operating at around 35-47 dB.

Our heat pumps have just been certified by Quiet Mark – recognition of exceptionally low-noise systems.

Sometimes. During your survey, we assess your existing radiators. In some cases, they’re suitable as is; in others, we may recommend a few upgrades for the most efficient operation.