Most people have a gas boiler in their home. Around three-quarters of UK households used a gas boiler as their main source of heating in winter 2025. But as gas prices have soared over the past few years, many people have looked at air-source heat pumps as a potential alternative.
Air-source heat pumps work very differently from a standard boiler. While the term “heat pump boiler” is common in searches, heat pumps aren’t boilers. They don’t burn anything to heat up the water. Instead, they pull warmth from the outside air and channel that into the heating system.
Gas boilers can provide quick hot water at the flick of a switch. But air-source heat pumps are more efficient, generally last longer, and can be more cost-effective once installed.
How Long Do Heat Pumps and Gas Boilers Last?
Expected Lifespan of an Air Source Heat Pump
An air source heat pump will typically last 15 to 20 years when correctly designed, installed, and maintained. Some systems may even last 20+ years. However, components such as the compressor, fan, pumps, or controls may require repair or replacement during that time.
Expected Lifespan of a Modern Condensing Gas Boiler
A modern condensing gas boiler won’t last as long as a heat pump. Usually, you can expect it to last 10 to 15 years when installed correctly and serviced regularly.
That said, it’s not uncommon for a good-quality boiler to remain operational for longer. The issue is that efficiency and reliability decline as components age.
Why Heat Pumps Can Outlast Gas Boilers
It all comes down to simplicity. Heat pumps have fewer combustion-related components: no burner, no flue, no combustion chamber. Because they work solely by pulling the heat from the air, they have a much lower operating temperature, reducing stress on the system.
Some of the components can still fail. But replacing a compressor, pump, fan, or even electronic controls is easier and can keep the system going for longer.
Which Is More Reliable?
Neither system is inherently more reliable.
Gas boilers are currently easier to repair simply because there are more available gas engineers. Heat pumps, on the other hand, have a longer overall service life. If you have a reliable heat pump repair service, an air source heat pump can be the better option.
The main problem with heat pumps is that they must be correctly sized for the home’s heating requirements. An undersized pump can struggle to supply enough heat, while an oversized unit may switch on and off too frequently.
Read more: How Heat Pumps Compare to Traditional HVAC Systems
Maintenance and Servicing Requirements for Longevity
Annual Gas Boiler Safety Checks and Common Repairs
Gas boilers require an annual safety check in rented properties. However, it’s sensible for all homeowners to book an annual check. The engineer will check combustion, the flue, safety devices, seals, pressure, and signs of leaks or corrosion.
If necessary, they’ll replace any broken or worn-out parts.
Cleaning and Protecting Air Source Heat Pump Fan Units
Air source heat pumps pull in outside air. That can mean leaves, vegetation, snow, and other obstructions can block the inflow. It’s important to regularly inspect the unit, clearing any debris.
Annual professional servicing is also recommended. The service should include coils, fan blades, filters, refrigerant pressure, electrical connections, water pressure, controls, and system performance. Homeowners should not open, dismantle, or pressure-wash the unit.
Heat Pump vs Gas Boiler Warranties
Warranties vary considerably by manufacturer and installer. Most modern gas boilers come with extended guarantees of 5-10 years when installed and registered correctly.
Heat pump warranties may be shorter, although extended warranties of 5–7 years are available through approved installers. Always check whether the warranty covers parts, labour, the compressor, controls, and the hot-water cylinder.
Can I Easily Replace a Gas Boiler With a Heat Pump?
Sometimes, but it’s rarely a like-for-like swap.
Many UK homes now use an air source heat pump as their primary source of heating. But it’s not exactly the same as the previous gas boiler.
The installer must complete a heat-loss calculation and assess the existing radiators and pipework. Some radiators may need enlarging because heat pumps generally circulate cooler water than boilers.
There must also be a suitable outdoor location, sufficient electrical capacity, and, unlike with a combi boiler, space for a hot-water cylinder.
The initial investment in a heat pump can seem sizeable. In England and Wales, homeowners can get a £7,500 grant as part of the Boiler Upgrade Scheme.
Which System Offers the Best Long-Term Investment?
Installation and Replacement Costs
Currently, air source heat pumps are more expensive to install. The typical air source heat pump installation costs around £12,000 before grants compared to around £3,700 for a gas boiler.
After the grant, however, the cost narrows substantially. Air-source heat pumps also tend to last longer and may have lower running costs.
Efficiency and Running Costs
A new gas boiler typically achieves around 85% efficiency in real-world use. A well-designed heat pump typically supplies three to four units of heat for every unit of electricity consumed. However, in the UK, electricity is substantially more expensive than gas, so more efficiency is not always cheaper.
Savings are more likely if replacing an old boiler or using a heat-pump tariff than replacing a new boiler model.
Long-Term Value
Heat pumps have a potentially longer life span, much higher efficiency, and lower emissions. With the grant scheme, they’re also comparable in price. Gas boilers have a lower upfront cost, simpler replacement, and currently have a larger repair network.
Heat pumps offer a stronger long-term investment when the property is suitable and installation is properly designed.
Which Heating System Is Right for Your Home?
There is no universal winner. A gas boiler is familiar, relatively inexpensive to replace, and easy to repair. A heat pump costs more upfront but can last longer, use far less energy, and offer better value over time. What matters is how well either system suits your home.
If you are curious about heat pumps but not quite ready to commit, come and see one in action at our Premium Heating, Plumbing & Cooling showroom. You can take a closer look, speak to our team, and get straightforward answers to your questions before deciding whether it is time to leave your gas boiler behind.
