Air-to-Air Heat Pumps Explained: Who Can Get the £2,500 Grant?

What to know first

These are the main points to understand before comparing air-to-air heating with other options.

An air-to-air heat pump may work well in a compact home without radiators. However, the grant is not simply a rebate on any wall-mounted air-conditioning unit. The installation must be designed as the home’s heating system and meet Boiler Upgrade Scheme rules.

The main questions are whether warm air can reach every room, how hot water will be produced and whether the equipment can be installed with the necessary permissions.

What changed in 2026?

Ofgem now lists a £2,500 grant for eligible air-to-air heat pumps. The updated rules apply to applications “properly made” from 28 April 2026. This means Ofgem must have the required information, owner consent and identity checks before treating the application as complete.

The scheme is installer-led. A Microgeneration Certification Scheme (MCS)-certified installer applies and must show the grant as an upfront reduction on the quote and invoice.

The temporary £9,000 off-gas-grid uplift, available from 21 July 2026 to 31 March 2027, applies to qualifying air-to-water and ground-source systems. It does not apply to air-to-air heat pumps.

Source status note: Energy Saving Trust’s consumer page, last updated on 16 July 2026, still says the air-to-air grant is not yet available. Ofgem’s live scheme information and Version 5.1 guidance show that qualifying applications have been covered since 28 April 2026. This article follows Ofgem’s operational position, checked on 20 August 2026.

Expert insight

“The grant changes the upfront calculation, but design remains the main test. A one-room unit may heat one space; the scheme requires whole-home space-heating capacity.”

Giles Crosse

Energy Editor

Experienced editor, journalist and communications consultant specialising in consumer energy and low carbon technologies.

• Editor and campaign author for Shell, EDF Energy and Good Energy.
• Consultant to the United Nations and contributor to the World Economic Forum.
• Journalist for Reuters, the BBC, The Economist and The Guardian.

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How does an air-to-air heat pump work?

An outdoor unit takes heat from the air and transfers it through pipes containing refrigerant — a fluid that carries heat — to indoor fan units. One outdoor unit may serve several rooms, while some homes use ductwork or an all-in-one unit.

Many systems can reverse the process for cooling. They recirculate indoor air, so the home still needs normal ventilation.

The comparison reflects current Energy Saving Trust technical information and Ofgem grant values. Individual products and designs vary.

Energy Saving Trust states:

Who can get the £2,500 grant?

The main conditions are:

• The installation must be at an eligible residential property in England or Wales.

• It will usually replace fossil-fuel or direct-electric heating. Existing heat pumps cannot normally be replaced through the scheme.

• A fossil-fuel boiler cannot remain as part of a hybrid system.

• The air-to-air heat pump must meet the full space-heating demand on its own.

• The complete design must meet the home’s space-heating and hot-water needs. Permitted non-fossil appliances, such as an immersion heater, may contribute.

• The installer and installation must meet MCS requirements.

• Social housing, including shared ownership, and most new-build homes are excluded. Some qualifying self-builds may be eligible.

• Previous public funding for the same installation may prevent eligibility.

The installer submits the evidence, but Ofgem decides whether the application and later grant claim meet the rules. Reading the conditions does not amount to pre-approval.

Good to know

A single-room price does not prove grant eligibility. The installer must certify a system capable of heating the whole property.

Which homes may suit an air-to-air system?

This matrix is a starting point, not an eligibility decision.

Energy Saving Trust identifies smaller homes and flats as possible candidates, while noting that equipment location, hot water and the number of indoor units need consideration. Planning and ownership restrictions remain separate questions.

Property type alone is not decisive. An installer should complete a room-by-room heat-loss calculation, which estimates how much heat each space loses in cold weather. The equipment plan should also cover indoor fan noise, visible units and refrigerant-pipe routes.

What might it cost, and what about hot water?

Energy Saving Trust’s page, updated on 16 July 2026, gives indicative costs of about £1,900 for one room and £3,700 for a three-bedroom semi-detached home. These are not fixed prices. A grant-eligible whole-home system may need several indoor units, electrical work, longer pipe runs, decoration or separate water heating.

The £2,500 is deducted from the eligible installation price; it is not paid to the owner. Compare itemised quotes covering equipment, installation, hot water and the grant.

Hot-water options include a cylinder with an immersion heater, an electric shower, point-of-use heaters or a dedicated heat-pump water heater. The overall design must meet the home’s space-heating and hot-water demand without relying on fossil fuel.

Bills cannot be predicted with certainty. Energy Saving Trust says UK performance data remains limited and that results depend on the heating being replaced, the system design and how it is used.

MCS gives a similar warning:

Ask installers to show the heat demand, expected electricity use, tariff and indoor-temperature assumptions behind their estimates. Cooling adds electricity use and should be considered separately.

What permissions and electrical checks may be needed?

In England, many domestic installations are permitted development if they meet all applicable conditions. These cover the MCS 020(a) planning standard, which includes a noise assessment, as well as outdoor-unit size and position. Extra restrictions apply to listed buildings, scheduled monuments and some conservation-area locations. A permitted-development installation cannot be used solely for cooling.

Wales updated its permitted-development rules on 1 June 2026. They also refer to MCS 020(a), siting and noise, and permit systems used for heating or for heating and cooling. Ask the local planning authority where the position is uncertain.

Good to know

Planning permission and freeholder consent are separate. A lease may require written consent for wall openings or an outdoor unit even when planning permission is unnecessary.

The installer should check the electricity supply and establish whether the local electricity-network company — the distribution network operator — needs notification or advance approval. Building Regulations or building-control requirements may also apply.

How does the grant application work?

1. Check the basic fit. Consider the layout, hot-water needs, outdoor-unit position and any planning, landlord or freeholder restrictions.

2. Get several MCS quotes. Compare certified installers using the same whole-home requirements. Ofgem and Energy Saving Trust both recommend obtaining multiple quotes.

3. Review the design. Check the heat-loss assessment, indoor-unit plan, hot-water arrangement, performance estimate and itemised £2,500 deduction.

4. Let the installer apply. Ofgem contacts the property owner for consent and identity checks. The owner normally has 14 calendar days to respond.

5. Track the voucher deadline. An air-to-air voucher lasts three months. It cannot be extended, although the installer may make a new application if it expires.

6. Complete and certify the work. The installer tests and signs off the system to MCS requirements, supplies the handover documents and asks Ofgem to pay the grant.

Ofgem consent allows the installer to make the scheme application. It is not the private installation contract. Check deposits, cancellation terms, warranties, complaints arrangements and the installer’s approved consumer-code membership before paying.

What support applies elsewhere in the UK?

The Boiler Upgrade Scheme covers England and Wales. As checked on 20 August 2026, Home Energy Scotland lists no grant for air-to-air systems, although other Scottish support exists. In Northern Ireland, households can check current schemes with the free NI Energy Advice service.

Key takeaways

• The £2,500 grant is live in England and Wales for qualifying applications from 28 April 2026.

• It is an installer-applied discount, not a payment to the owner.

• The heat pump must cover the home’s full space-heating demand.

• Hot water normally needs a separate non-fossil solution.

• Smaller homes may be good candidates, but layout and permissions matter.

• Costs and bill savings are property-specific, not guaranteed.

Frequently asked questions