Air to air heat pump costs: install, run and grant

In short

Purchase and installation cost

As at July 2026. London and the South East typically run 20 to 30 per cent above these ranges.

Roughly, a 12,000 BTU wall-mounted system breaks down as about £750 for the equipment and about £1,150 for labour, materials, commissioning and F-Gas certification.

What sits inside a proper quote: the indoor and outdoor units, refrigerant pipework, condensate drain, electrical connection, commissioning and the F-Gas certificate. What frequently sits outside it: the dedicated electrical circuit, making good and redecoration, long pipework runs at £200 to £300 extra for loft or cross-floor routing, and scaffolding or access equipment.

Our full UK air conditioning cost breakdown covers this room by room.

The grant, and the catch in the specification

The £2,500 Boiler Upgrade Scheme grant is available in England and Wales where an air-to-air system replaces your existing fossil fuel or direct electric heating and becomes the property's primary heat source. Your boiler comes out; there is no hybrid option.

Critically, scheme rules require an indoor unit in every occupied room. That means the grant-eligible specification is a whole-home system, not a single unit. It changes the arithmetic in a way most cost guides miss.

A larger, grant-eligible system can land at a lower net cost than a smaller one that does not qualify.

Two things to be aware of before you budget on that basis. First, air-to-air systems are not currently covered by the zero VAT relief that applies to some other low-carbon technologies, so confirm the applicable VAT rate with your installer. Second, MCS product certification for air-to-air is still being completed, so check where the grant actually stands before you rely on the £2,500.

Running costs: cooling

At the Ofgem price cap for 1 July to 30 September 2026, electricity is 26.11p per kWh including VAT.

A hot week of evening use in one bedroom, say five hours a night for seven nights, comes to roughly £6 to £7. All-day use across three rooms through a heatwave fortnight is where the bill becomes noticeable.

Inverter models, which vary compressor speed rather than cycling on and off, use materially less than fixed-speed units. Every current mainstream domestic system is an inverter, but it is worth confirming on a budget quote.

Running costs: heating, and the honest comparison

This is the number people actually want, and the honest answer is that it is close.

Efficiency is measured as SCOP, the seasonal coefficient of performance: heat delivered divided by electricity consumed, averaged across a heating season and tested to EN 14825. Air-to-air systems typically return SCOP 3.0 to 4.0.

On a typical three-bedroom semi using around 12,000 kWh of heat a year, that is roughly £900 against roughly £960. A £60 difference, which is inside the margin of error on almost any household.

The break-even point is a SCOP of about 3.5. Above it, you save. Below it, you pay more. Which is why the SCOP of the specific model matters more than the brand on the front of it.

Four things shift the answer. Tariff: a specialist heat pump or time-of-use tariff at 14p to 17p per kWh blended moves air-to-air to roughly 4p to 5p per kWh of heat and comfortably under gas. Standing charges: disconnecting gas removes 29.04p a day, about £106 a year. Insulation: a poorly insulated solid-wall property makes any heat pump look bad because the heat demand itself is the problem. Room coverage: air-to-air only heats rooms with a unit in them, so if you end up running electric heaters in the hall and bathroom the headline efficiency stops meaning much.

Why some systems cost far more to run than expected

If your running costs are well above these figures, the cause is usually one of five things. An undersized unit working at maximum output constantly instead of modulating. An oversized unit short-cycling, hitting temperature and switching off repeatedly. Dirty filters, which is the most common and the easiest to fix, so clean them monthly in season. A standard variable tariff rather than a heat pump or time-of-use tariff. Or treating it like a boiler, switching it on and off for short bursts rather than running it steadily at a lower setting.

Heat pumps of every type reward steady low-output operation. Blasting a cold room to 24°C for an hour is the expensive way to use one.

Servicing and lifespan

Annual servicing runs £80 to £150. Filters are owner-maintainable. A well-installed system should give 12 to 15 years, longer with regular servicing, which compares reasonably with a gas boiler at 10 to 15.

Frequently asked questions