For years the Boiler Upgrade Scheme (BUS) only paid towards heat pumps that heat water for radiators or underfloor heating. That has changed. The scheme now includes a grant towards an air-to-air heat pump, the type of system most people simply call air conditioning. The Energy Saving Trust puts it plainly: air-to-air heat pumps are sometimes referred to as air conditioning.
The headline figure on GOV.UK is £2,500 towards an air-to-air heat pump. That is a real help on the cost of a whole-home system, but it is not a discount on any air conditioning you like. The grant exists to replace fossil-fuel heating, and every condition follows from that. This guide sets out the rules, who doesn’t qualify and how the application works. It is general information, not financial advice.
How much the grant is, and for what
The scheme runs in England and Wales. GOV.UK lists three amounts:
| System | Grant |
|---|---|
| Air source heat pump (air-to-water) | £7,500 |
| Ground source heat pump | £7,500 |
| Air-to-air heat pump | £2,500 |
Until March 2027 there is also an extra £1,500 for an air source or ground source heat pump in a home heated by oil or LPG with no mains gas connection. That top-up is for air-to-water and ground source systems, not air-to-air. The grant amounts are set in law in The Boiler Upgrade Scheme regulations (SI 2026/390).
The conditions for air-to-air
An air-to-air system only qualifies if all of these are true:
- It replaces your existing fossil-fuel heating. Gas, oil, LPG or direct electric heating comes out, and the heat pump becomes the heating system.
- It meets the home’s full heating demand. Every heated room needs to be covered. A single unit in the lounge, with the boiler still doing the rest, won’t qualify.
- It is not an add-on alongside a boiler. Hybrid systems, where a heat pump works with a boiler, are excluded.
- It is in a home. The air-to-air grant is for domestic properties.
- It is designed and installed by an MCS-certified installer and meets the scheme’s standards, such as minimum efficiency.
In practice that usually means a multi-split or several split systems sized room by room, with a heat loss calculation behind them. It also means thinking about hot water, because an air-to-air heat pump heats air, not your taps and shower. If the boiler goes, hot water needs another source, such as an electric cylinder.
Want it done properly? AirCon Doctor installs, repairs and services air conditioning and heat pumps across London and the South East, from our base in East Grinstead. We’re an F-Gas certified company and NICEIC approved. Get a fixed-price quote.
Who doesn’t qualify
GOV.UK’s eligibility page lists several exclusions that apply to the whole scheme:
- most new build properties, including homes a developer is still building;
- social housing;
- a property that has already had government funding for a heat pump or biomass boiler (one grant per property);
- replacing a low-carbon system, such as swapping one heat pump for another;
- hybrid heat pump systems.
You must own the property. And for air-to-air specifically, a cooling-led install that leaves the boiler in place is the most common reason a project falls outside the grant. That’s fine: plenty of people want air conditioning for summer comfort and keep their boiler. They just pay for it without BUS.
How to apply: your installer does it
You don’t fill in an application form yourself. GOV.UK’s how to apply page says the installer applies on your behalf through Ofgem. The steps are:
- Contact MCS-certified installers and ask for quotes. GOV.UK has a find a heat pump installer page.
- The installer checks and confirms your eligibility.
- You agree a quote. The grant is taken off the price you pay and shown on the quote and invoice.
- Ofgem contacts you to confirm the installer is acting for you. Ofgem or MCS may check the installation later.
The heat pump must be commissioned within 120 days of the application, so don’t sign up for a grant months before you are ready to start.
Is air-to-air the right choice for the grant?
The air-to-air grant is smaller than the air-to-water one, but an air-to-air system can suit homes where radiators are small, where cooling matters, or where a wet system would be disruptive to install. An air-to-water system keeps your radiators and heats hot water, and attracts the larger grant. Our guide to the difference between heat pumps and air conditioning goes further.
We are MCS certified and can design either type. For air-to-water systems our price range is £8,000–£16,000 at 0% VAT on homes, before the £7,500 grant. For air-to-air we survey first, because the grant only works if the design covers the whole home. We then give you a fixed-price quote with the grant shown.
Quick answers
Can I get the £2,500 grant for one air conditioning unit?
Not if your boiler or other fossil-fuel heating stays. The system must replace that heating and meet the home’s full heating demand.
Do I apply to Ofgem myself?
No. Your MCS-certified installer applies on your behalf. Ofgem then contacts you to confirm the installer is acting for you.
Can landlords get the grant?
GOV.UK says you must own the property, and that properties you rent to tenants and second homes can qualify. The air-to-air grant is for homes only. Social housing is excluded.
Is the oil and LPG top-up available for air-to-air?
No. The extra £1,500 until March 2027 applies to air source (air-to-water) and ground source heat pumps in homes heated by oil or LPG with no mains gas.
Related services
More advice
- Heat Pump vs Air Conditioning: What’s the Difference?
- Air Source Heat Pump Cost UK 2026: Complete Guide
- 0% VAT on Air Conditioning and Heat Pumps: What HMRC Says
- Air Conditioning in Winter: Using Heat Pump Mode Effectively
- All advice
This guide is general information, checked against the sources linked on 30 October 2026. It isn’t legal, tax or financial advice. Rules, grants and product ranges change, so check the current position before you rely on it.