The Boiler Upgrade Scheme, explained for cooling

The Boiler Upgrade Scheme (BUS) is the UK government grant scheme for low-carbon heating. Most coverage frames it as a heating story, but there is a cooling angle that matters if your home overheats: the scheme includes a £2,500 pathway for air-to-air heat pumps, which cool in summer and heat in winter from the same unit. This is the only route by which a "cooling" system can be part-funded - and it comes with a firm condition most sales pages gloss over.

The two honest branches

Eligible - you replace your heating. You are eligible for the £2,500 grant when an air-to-air heat pump replaces your fossil-fuel or electric heating and is fitted by an MCS-certified installer. The heat pump then does your heating as well as your cooling, and the old system is decommissioned, not kept alongside it. On this route a system that costs a few thousand pounds installed can come down substantially once the grant is applied.

Not eligible - you keep your heating. If you keep your boiler and add cooling as an extra, that is a cooling-only add-on, and it is not eligible for the £2,500 grant - whatever your current heating type. A private-pay air conditioning unit (a single-split, for example) is a perfectly good answer for one hot room, but it is an F-Gas / REFCOM job with no grant - not MCS, which applies only to the grant-eligible heat-pump route.

The word that decides it is replace. Adding air-to-air and keeping your boiler does not qualify; replacing your heating with it can. (Grant rules as of August 2026 and subject to change.)

Eligible does not yet mean payable. Air-to-air entered the scheme on 28 April 2026, so the grant is law. But only an MCS-certified installer can claim it, and only against a product on the MCS Product Directory - and no air-to-air product is listed there yet, so no compliant voucher can currently be issued. MCS 007 v8.0 brings air-to-air into scheme scope from 5 December 2026. Our honest guide to the £2,500 grant explains what that means for timing your install.

Why the honesty matters here

This is a mis-selling-scarred category. Around 33% of an inner-London borough like Islington sits inside a conservation area, and the incumbents chasing grant clicks often imply the £2,500 is more or less automatic. It is not - eligibility is per-property, it turns on your current heating and your willingness to replace it, and the accreditation has to match the route.

That is exactly the kind of thing worth checking against your specific address rather than a generic promise.

Check your real eligibility

Our free cooling checker pre-fills your home from public property data (EPC and UPRN records) and gives you your real grant position - eligible or not, and why - alongside the right system, the planning position and a net cost. You see it on screen, straightaway, with no phone call and no cold-calling, ever.

Check your home in 60 seconds ▸