Last Updated on June 19, 2025
Replacing your gas boiler with an air source heat pump is a significant investment that can transform your home’s heating efficiency and reduce carbon emissions. Understanding the cost to replace a gas boiler with a heat pump is essential before making the switch, especially in 2025 when new technologies and government grants can affect prices.
This guide breaks down the factors that influence cost, additional home improvements like insulation, and why getting a tailored quote from Eco Happy is a smart first step.
Contents
- 1 How Much Does It Cost to Replace a Gas Boiler with a Heat Pump?
- 2 What Factors Affect the Cost to Replace a Gas Boiler with a Heat Pump?
- 3 Why Is Improving Insulation Important When Replacing a Gas Boiler with a Heat Pump?
- 4 Ready to Discover Your Exact Cost? Request Your Free Air Source Heat Pump Quote Today!
How Much Does It Cost to Replace a Gas Boiler with a Heat Pump?
The overall cost to replace a gas boiler with an air source heat pump depends on several key factors, including the size of your property, the type of heat pump, and the existing heating system.Â
On average, UK homeowners can expect to pay between £8,000 and £18,000 for a full installation, including the removal of the old boiler.
| Cost Factor | Typical Range (GBP) | Notes |
|---|---|---|
| Air Source Heat Pump Unit | £5,000 – £9,000 | Depends on brand, efficiency, and capacity |
| Installation and Labour | £2,000 – £5,000 | Complexity, location, and installer rates |
| Boiler Removal and Disposal | £300 – £600 | Some companies include this in installation price |
| System Modifications (e.g. Radiators or Underfloor Heating) | £1,000 – £3,000 | May be required for heat pump compatibility |
| Additional Insulation Work | £500 – £2,500 | Recommended to maximise heat pump efficiency |
| Grant Contributions (e.g. Heat Pump Grants) | -£4,000 to -£6,000 | Depending on eligibility and schemes available |
Costs vary widely depending on property specifics and installation complexity.
How do running costs compare when replacing a gas boiler with a heat pump?
A common concern is how much electricity an air source heat pump uses and how that compares to gas boiler fuel costs. Although heat pumps consume electricity, they are much more efficient, often delivering 3 to 4 kW of heat for every 1 kW of electricity used.
Understanding heat pump running costs and how efficient they are can help you better estimate your monthly energy bills. Also, the best heat pump brands can provide more efficient units that reduce ongoing costs.
What Factors Affect the Cost to Replace a Gas Boiler with a Heat Pump?
Several elements directly influence the final cost when swapping your gas boiler for a heat pump:
- Property Size and Heating Demand: Larger homes require bigger heat pumps or multiple units. Therefore, knowing what size air source heat pump you would need is vital.
- Existing Heating System Compatibility: Older homes with traditional radiators may need upgrades to larger or more radiators, or installation of underfloor heating to work efficiently. If you are wondering whether you can keep your current radiators or need to replace them, check out our post on using a heat pump with existing radiators for expert advice.
We often get asked, do air source heat pumps work in old houses? The answer is yes, though older properties may require some adjustments like improved insulation or radiator upgrades to maximise efficiency. - Insulation and Property Suitability: Poorly insulated homes lead to higher heat loss, requiring more powerful and costly systems. That being said, it’s important to assess whether your house is suitable for a heat pump.
- Climate Considerations: Homes in colder regions of the UK may require heat pumps that maintain efficiency in low temperatures. Check out our guide on how heat pumps work in cold weather for more insight.
- Installation Complexity: Access to the property, plumbing, and electrical work can affect labour costs.
- Government Grants and Incentives: The UK government offers heat pump grants which can significantly offset costs. One of the most notable is the Boiler Upgrade Scheme (BUS).
Why Is Improving Insulation Important When Replacing a Gas Boiler with a Heat Pump?
Heat pumps work most efficiently when your home retains heat well. Unlike gas boilers, which produce high-temperature heat, heat pumps operate best at lower temperatures. Without good insulation, you risk higher running costs and lower comfort.
Upgrading your loft insulation, cavity wall insulation, and draught-proofing doors and windows can reduce heat loss dramatically.
Improving insulation also helps answer questions such as are heat pumps worth it by ensuring you get the most from your investment.
Ready to Discover Your Exact Cost? Request Your Free Air Source Heat Pump Quote Today!
Don’t leave your heat pump investment to guesswork. Get a free, personalised quote from Eco Happy today and take the first step towards greener, more efficient heating.
Whether you’re a homeowner, landlord, or commercial property manager, our expert team will provide transparent pricing, system advice, and help you maximise available grants.
Request your free air source heat pump quote now and start saving on energy bills while reducing your carbon footprint!
James Elston
Boiler Expert
James Elston is the top boiler replacement and heating expert at Eco Happy. He has over 20 years of experience in the industry, focusing on Gas Safe boiler installations and offering home-heating and energy-saving solutions to homeowners across the UK. From sourcing the most energy-efficient combi boiler to providing specialist heating advice, James ensures that Eco Happy maintains the highest standards and best customer service.