Air to Air Heat Pump Grant: The £2,500 BUS Category Explained

A £2,500 government grant now covers air-to-air heat pumps under the Boiler Upgrade Scheme — and an air-to-air heat pump is the same underlying equipment as a split-system air conditioner. That overlap is the actual story here: the same unit that cools your bedroom in summer can now come with a grant toward it, if your home qualifies.

Grant details last verified: 31 August 2026, against Ofgem’s Boiler Upgrade Scheme guidance.

What the grant actually covers

As of 28 April 2026, the Boiler Upgrade Scheme (England and Wales) offers:

Heating system	Grant amount
Air-to-air heat pump	£2,500
Air source heat pump (air-to-water)	£7,500
Ground source heat pump	£7,500
Water source heat pump	£7,500
Biomass boiler	£5,000

The £2,500 air-to-air category is new — previously, air-to-air wasn’t grant-eligible under this scheme at all. It’s smaller than the £7,500 figure most heat pump coverage focuses on, because air-to-air only heats the room’s air, not your water — but for a piece of equipment most homes only knew as “air conditioning,” a dedicated grant category is the genuinely new part of this story.

The eligibility rule most coverage leaves out

Before assuming your home qualifies for the £2,500 air-to-air route specifically, know this: it’s ring-fenced to homes currently on direct electric heating — storage heaters and the like — not homes on gas, oil, or LPG. If your home has a gas boiler, the air-to-water route (£7,500) is generally the one you’d actually qualify for, not air-to-air. This distinction matters because most of the coverage of the £2,500 figure doesn’t mention it, and it’s the difference between a genuinely relevant grant and one that doesn’t apply to your situation at all.

A few other things worth knowing before assuming you qualify:

• England and Wales only. Scotland and Northern Ireland run their own, separate schemes with different rules and amounts — check the equivalent scheme for your nation rather than assuming these figures apply.
• You don’t apply for the grant directly. Your installer applies on your behalf and deducts it from the quoted price upfront.
• The installer must be MCS-certified, and a member of an approved consumer code (RECC or HIES). This isn’t optional paperwork — it’s how the grant gets paid at all. See our guide to finding a reliable installer for how to check this properly.
• Get quotes from at least three installers, same as with any heat pump installation — the grant is a discount on the job, not a reason to skip comparing quotes.

The distinction that actually matters: air-to-water vs air-to-air

Most UK heat pump installations funded through the Boiler Upgrade Scheme are air-to-water systems — they extract heat from outside air and use it to heat water, which then runs through radiators, underfloor heating, or your hot water cylinder. This is a direct, like-for-like replacement for a gas boiler, and it’s what most installers default to. The catch: a standard air-to-water system generally can’t cool your home without extra equipment most installations don’t include — things like fan-coil units, or underfloor heating specifically designed and rated for cooling rather than just heating. Retrofitting cooling onto an existing radiator-based system isn’t a simple software toggle.

Air-to-air heat pumps work differently: they extract heat from outside air and blow conditioned air directly into a room, exactly the way a split-system air conditioner does — because it genuinely is the same underlying technology. Run in reverse, that’s efficient cooling, typically with a coefficient of performance (COP) of 3–4 in cooling mode, meaning 3–4 units of cooling for every unit of electricity used.

If you’re not sure which type you have, or which type an installer is quoting you, ask directly — “air-to-water” and “air-to-air” are the exact terms to use.

Who this is actually worth considering for

If you don’t have any heat pump yet and want heating and cooling from one system: an air-to-air heat pump is genuinely worth putting on your shortlist alongside a standard air-to-water system, especially if you’re in a warmer part of the UK or a room that struggles in summer regardless of season. Weigh it against a traditional gas boiler replacement (air-to-water, no cooling) and against a portable AC unit (see our portable air conditioner buying guide) bought separately for just the room that needs it.

If you already have an air-to-water heat pump for heating and hot water: the practical route to adding cooling usually isn’t retrofitting that system — it’s adding air-to-air units in the specific rooms that need it, most commonly a bedroom or living room. That’s a separate, additional installation, not an upgrade to what you already have.

Either way, this is the same underlying category of product covered in our comparison of portable AC, split systems, evaporative coolers and fans — an air-to-air heat pump is a permanently installed split system, discussed here specifically for the heating-and-cooling and grant angle rather than as a standalone product category.

Finding an installer

Any installer you use must be MCS-certified for the grant to apply. Octopus Energy’s Trusted Partners network is one starting point for finding a vetted installer offering air-to-air heat pumps and air conditioning — but get quotes from at least two or three installers regardless of where you start, the same advice that applies to any heat pump installation.

This guide is general information to help you weigh up the option — always get a proper site assessment from a certified installer before committing, and see our disclaimer for the full picture.