Is an air source heat pump worth it?

The honest pros and cons of air source heat pumps, who benefits most and when a heat pump might not be the right choice.

For most UK homes, an air source heat pump is worth it, particularly now the £7,500 Boiler Upgrade Scheme grant and 0% VAT have brought the upfront cost close to that of a new boiler. Whether it's right for your home depends on your current fuel, your home's heat loss and how the system is designed.

The pros of an air source heat pump

  • £7,500 grant takes a big chunk off the price.
  • 300 to 400% efficient, so you buy much less energy.
  • Lower bills for homes on oil, LPG or electric heating, and often on gas with a heat pump tariff.
  • Around 70% lower heating emissions than gas, falling further as the grid decarbonises.
  • Long life of around 20 years and low maintenance.
  • Safe: no combustion, no flue, no carbon monoxide.
  • Future-proof: works with solar panels, batteries and smart tariffs.

The cons

  • Higher upfront cost than a boiler before the grant.
  • Space needed for an outdoor unit and hot water cylinder.
  • Radiator upgrades may be needed in some rooms.
  • Running costs depend on design and tariff: a poor install can be expensive to run.
Typical UK semi-detached house suitable for an air source heat pump

Who benefits most from a heat pump?

  • Off-gas homes on oil, LPG or electric storage heaters.
  • Homes with an old boiler due for replacement anyway.
  • Reasonably insulated homes with space for a cylinder.
  • Homes with solar panels, which can power the heat pump directly.

Payback

Against oil, LPG or electric heating, the combination of the grant and lower running costs often means a heat pump pays back its extra cost within a few years. Against gas, the case rests more on the grant, a heat pump tariff and the longer lifespan. Your installer can give you an estimate based on your actual heat demand.

When a heat pump may not suit

A heat pump may not be the best fit if there's nowhere to site the outdoor unit, no possible space for a cylinder, or if the property is very poorly insulated and can't be improved. A survey will tell you, and it's free.

Sources

Grant amounts, VAT rules and eligibility are set by government and the scheme administrators. We check them against these primary sources:

New to the jargon? See the heat pump glossary, or browse the heat pump FAQs.

Questions

The things people ask us first

If yours isn't here, ask on the form and an adviser will answer it on the call.

Is an air source heat pump worth it?
For most homes coming off oil, LPG or old electric heating, yes: running costs usually fall and the £7,500 grant covers much of the installation. Against mains gas the savings are smaller and depend on your tariff and how well the system is designed, but you cut your heating carbon emissions by around 70% or more.
Is an air source heat pump expensive to run?
Not if it's designed well. A heat pump with a SCOP of 3 to 4 uses a third to a quarter as much energy as a boiler. Poorly sized systems or high flow temperatures are the usual cause of high bills, which is why the heat loss survey matters.
Are air source heat pumps noisy?
Modern units are quiet: typically 40 to 55 dB at one metre, similar to a fridge or a quiet conversation. Your installer must complete an MCS noise assessment to confirm the unit meets permitted development limits at your neighbour's nearest window.
What are the disadvantages of air source heat pumps?
Higher upfront cost than a boiler (before the grant), the need for space for an outdoor unit and hot water cylinder, possible radiator upgrades, and lower efficiency in very cold spells. Most of these are addressed by good system design.
Do heat pumps work in cold weather?
Yes. Air source heat pumps extract heat from outside air down to around -20°C and are used widely across Scandinavia. Efficiency dips on the coldest days, which is why a correctly sized system matters, but a well-designed install keeps a UK home warm all winter.
How long does an air source heat pump last?
Around 20 years with an annual service, compared with 10 to 15 years for a typical gas boiler. Most manufacturers offer 7 to 10 year warranties when the unit is fitted by an approved installer.
Get started

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