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The ‘Boiler Upgrade Scheme’ Explained

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The government has announced a new scheme ‘The Boiler Upgrade Scheme’ (BUS) to provide grants to property owners to install low carbon heating systems such as heat pumps.

Latest update - October 2023

What the Net Zero Strategy update means for homeowners heating their homes?

What we know so far:

  • The Boiler Upgrade Scheme (BUS) grant has been increased to £7,500 to enable homeowners money off heat pump installs in England & Wales.
  • The proposed phase-out on the installation of fossil fuel appliances is 2035 this now includes LPG, oil and coal appliances.


Q: What do we do if we’ve already had the application approved at the previous value?

A: If you have already applied for your BUS voucher but not yet had your heat pump installed, you will only be eligible for the original amount of £5,000 for an air source heat pump and £6,000 for ground source heat pump. You are able to revoke your current voucher and reapply after Monday 23 October where you may be able to receive the higher value of £7,500.

You can find out more about BUS here.

What is the Boiler Upgrade Scheme?

The Boiler Upgrade Scheme (previously referred to as the Clean Heat Grant) is the latest iteration of the Government’s financial support of low carbon heating. This scheme is designed to help attain the UK’s net zero emissions target by 2050 by making low carbon technologies more affordable to install by reducing the upfront cost. Previously, this support was provided in the form of the Renewable Heat Incentive (ended March 2022).

This support is aimed at encouraging homeowners in England and Wales to upgrade their current fossil fuelled boiler heating and hot water systems to more energy-efficient heat pumps in an effort to decarbonise their home’s heating . The scheme is expected to run until 2028, and has been earmarked a budget of £450 million over the three years as part of an almost £4bn strategy to help cut carbon emissions.

Note: For those living in Scotland, please click here to find out more about the HES funding. In Northern Ireland, there may be alternative funding available.

How does the Boiler Upgrade Scheme Work?

The Boiler Upgrade Scheme was announced as part of the Government’s Heat and Buildings Strategy and is open to all eligible domestic property owners in England and Wales . The aim of the scheme is to reduce the cost of installing low carbon heating systems to encourage more homeowners to move away from fossil-fuel based systems. Compared to fossil fuel systems such as traditional boilers, low carbon alternatives are typically more costly to install, and this can therefore be a barrier for homeowners looking to change or upgrade their existing system. The most common low carbon alternatives are heat pumps and biomass boilers, with the scheme providing funding for both air source and ground source heat pumps, as well as biomass boilers for off-grid properties.

The BUS operates in the form of a grant voucher which is provided to the installer after installation and commissioning, with the expected amount deducted from the homeowners upfront cost.

Key dates:

1st April 2022 -

  • Low carbon heating systems that are commissioned on or after this date will be entitled to support under the scheme. (Commissioning is the completion of installation and setup of the system).

11th April 2022 -

  • Installers are able to open an account for the scheme with Ofgem, the scheme administrator.

23rd May 2022 -

  • The scheme opens for grant applications and payments.

Watch the video 'Heat Pump Considerations and Expected Costs' for more info about typical heat pump installation considerations, including associated costs:

What funding is available through the Boiler Upgrade Scheme?

The Boiler Upgrade Scheme provides funding in the form of a grant of up to £7,500 to reduce the upfront installation cost of your chosen low carbon system. This grant is applied for by your installer and should be discounted from the total cost of your installation within their quote.

Dependent on your eligibility, you may be able to claim the following:

  • £7,500 off the cost and installation of an air source heat pump
  • £7,500 off the cost and installation of a ground source heat pump (includes water source)
  • £5,000 off the cost and installation of a biomass boiler

It should be noted that for any heat pump to be eligible for the grant, it must have a seasonal coefficient of performance (SCOP) of at least 2.8. It is also important to note that, in this instance, the Government seem to include water source heat pumps to be within the same category as ground source heat pumps.

Biomass boilers are only eligible for this scheme in very limited circumstances, such as if they are in rural locations and in properties that are not connected to the gas grid (heat pumps are eligible either on or off the gas grid). For more information, please check your eligibility through the government website.

Watch the video 'Heat Pump Considerations and Expected Costs' for more info about typical heat pump installation considerations, including associated costs:

Who can apply for the Boiler Upgrade Scheme?

Eligibility Criteria:

You may be eligible if you:

  • live in England or Wales
  • own your property (whether this is a home or a small non-domestic property)

Property eligibility

The property will need to have:

  • a valid Energy Performance Certificate (EPC) with no outstanding recommendations for loft or cavity wall insulation (unless you have an insulation exemption)

You can find and check your EPC certificate through the website.

If you do not have loft or cavity wall insulation, you may still be eligible for the Boiler Upgrade Scheme provided the required installation is fitted prior to installation. Your local renewables installer should be able to inform you further of your homes’ specific eligibility following a consultation.

New build properties and social housing are not currently eligible for the Boiler Upgrade Scheme with the exception of custom-build properties (such as if you are building your own home). Custom new builds do not require an EPC, but must principally be built with the labour and resources of the first owner and must be owned by an individual.

Technology eligibility

For your chosen low carbon technology to be eligible for the scheme, it must:

  • be commissioned on or after 1st April 2022
  • fully replace an existing fossil fuel system (such as oil, gas or direct electric)
  • have an installation capacity of no more than 45kWth (this covers most homes)
  • meet the full space heating and hot water demands of the property

If you are unsure whether your property has the installation capacity required to be eligible for the BUS, contact your local installer and they will be able to inform you further. Your local renewables installer will also be able to advise you whether a low carbon heating system is suitable for your property, and which system is the most efficient for your needs.

Any heat pump must have a seasonal coefficient of performance (SCOP) of at least 2.8

Unfortunately, conventional hybrid systems that use a fossil fuel source are not included in the eligibility for this scheme, and neither are solar thermal heating systems. However, if a hybrid system is installed with a heat pump and solar thermal, then this may be eligible providing the heat pump covers all of the heat and hot water requirements (as there is no specific funding for solar thermal systems themselves).

For further eligibility criteria and exceptions, please review the government legislation and speak to your local renewables installer.

How can I apply for the Boiler Upgrade Scheme?

Application for the Boiler Upgrade Scheme grant is available only to MCS (Microgeneration Certification Scheme) accredited renewables installers and is conducted through Ofgem, the Government’s scheme administrator.

If you believe that you will be eligible for the scheme, contact your local Vaillant MCS accredited installer. From here, the process will be as such:


Your installer will then further advise you on whether your proposed installation is eligible for a grant.


Your installer will then send you a quote for the installation which should include the deduction for the BUS grant.


Your installer will then provide your details to Ofgem, who will then contact you (via email) to confirm that you give consent for the installer to apply on your behalf.


Your installation will then be carried out and completed in line with both the industry standard and the requirements of the Boiler Upgrade Scheme.


The installer will then redeem the grant voucher and receive the grant following the full installation and commissioning. This voucher must be redeemed 3 months of the issue date for an air source heat pump or biomass boiler, and within 6 months of the issue date or 31st March 2028 (whichever is earlier) for a ground source heat pump.


For more legislation-specific information, please find our list of government resources below:

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Page updated 26/10/2023