Heat pump vs boiler: find the right heating solution for you.

Boiler vs heat pump

Kitting out any home calls for decisions, big and small. And whether you should opt for a heat pump or a new boiler is likely to be one of the bigger ones. 

So, to help you choose, we’ve explored the essential factors to consider. Whether you’re aiming for reduced heating costs, energy efficiency or a lower carbon footprint, read our comprehensive guide to finding the right solution for your home.

What heating systems are available in the UK?

The good old gas boiler (now increasingly thought of as not-so-good where the environmental impact is concerned) is by far the most common form of domestic central heating, relied upon by around 74% of households in England and Wales.1 

But now heat pumps are on the rise. They work best in homes that are well insulated, and to reap maximum benefits may require the adaptation of existing radiators or underfloor heating. They can also keep you cool in summer, as well as warm in winter, and may be able to provide you with hot water. And heat pumps look set to become even more common, thanks to the government’s ambitious target to install 600,000 of them a year by 2028.2

There are two kinds to choose from: air source heat pumps and ground source heat pumps. We’ll come on to the differences between them later – but currently the air source variety are the more popular of the two.3 

That said, other heating systems are available, including:

  • Oil – the fuel for which you’ll need to buy in bulk, requiring a storage tank that sits outside your home.

  • Liquid Petroleum Gas (LPG) – which, like oil, is a fossil fuel, so not a sustainable option.  

  • Electric – given that electricity is currently more expensive per unit than gas, this is a more viable choice if you generate your own – for example, via solar panels.4

  • Renewable – including biomass, which it can be argued is a form of renewable energy, since it relies on the growing of greenhouse gas-absorbing plants or trees, before being harvested and used as fuel.5

Let’s start with the two most popular options around. 

Air source heat pump vs gas boiler.

Price-wise, while costs vary you can expect to pay about £3,700 for a straightforward gas boiler replacement with thermostatic radiator valves.6

For an air source heat pump, the upfront cost rises to around £14,0007, though with a grant of £7,500 from the Boiler Upgrade Scheme, that’s less of a difference than it first appears.

Running costs.

How much an air source heat pump can save you on your energy bills depends on the kind of traditional boiler you’re replacing. In the case of an old G-rated gas boiler, that can be around £340 a year.7 

By comparison, a brand new A-rated gas boiler may actually be cheaper to run than an air source heat pump, though only by about £14 a year.7 And of course the heat pump can offer you big benefits in reducing your carbon footprint. Talking of which… 

Carbon emissions. 

For CO2, an air source heat pump’s lower-carbon credentials can amount to a saving of about 2,900 kg/year for a G-rated boiler. For an A-rated boiler, it’s a still-impressive 1,900kg/year.7 


Gas boilers are suited to all types of properties, including flats. Not surprisingly given how long they’ve been around, they’re quick and straightforward to install, usually in just a few hours. And of course there are plenty of qualified and experienced gas engineers out there ready to do it. 

Heat pumps, on the other hand, require a garden or outside space, because the main unit sits outside your home. And since they’re relatively new, at least for now there are fewer qualified installers around. Lucky for you, if you choose to buy a heat pump with us, professional installation by E.ON is included.

Heat pump explainers: What a heat pump installation looks like.

Learn about how an air source heat pump works and how we would install a heat pump in your home. A heat pump is an energy-efficient solution that can provide heating and cooling for your home.

Air source heat pump vs oil boiler.

Running costs.

In comparison with an oil boiler, an air source heat pump wins hands down. Again, the kind of boiler you’re replacing makes a big difference, but there are certainly savings to be made – around £510 with a G-rated oil boiler, and £65 on an A-rated one.7   

Carbon emissions.  

As you might expect against a fossil fuel like oil, the carbon savings are significant too. They range from about 4,400 kg/year for a G-rated oil boiler, to 2,900 kg/year for an A-rated model.7


If you currently have an oil boiler, chances are you have an outside tank for storing the oil. And since outside space is a must-have for a heat pump, your home may be ideal for making the switch. 

Air source heat pump vs LPG boiler.

Running costs.

The savings you stand to make by switching from an LPG boiler to air source heat pump are similar to an oil boiler. Again, about £510 for a G-rated one, and as much as £100 for an A-rated boiler.7

Carbon emissions. 

The annual CO2 savings are slightly less than with an oil boiler, but still well worthwhile. They come in at around 3,400 kg/year for an old G-rated LPG boiler, and 2,200kg/year for a more efficient A-rated version.7


As with an oil boiler, since an LPG model requires you to have a tank outside your home, switching to an air source heat pump could well be a viable option. 

Air source heat pump vs ground source heat pump.

They’re two bits of kit based around a similar idea. Namely, taking the heat from the environment and bringing it inside via a heat exchanger, in a way that creates less carbon than many other forms of heating.8

The biggest difference is right there, in the name. While an air source heat pump extracts heat from the air (yes, even when it’s chilly), a ground source heat pump takes it out of the ground. It’s an example of geothermal energy, and it’s harnessed by sinking boreholes, underground pipes and pumps into the earth on your property. Learn more about how air source heat pumps work

Which heating system is right for your home?

If you’re thinking of making changes to your central heating system, the rising popularity of heat pumps makes them well worth considering. But whilst in many ways they’re the more eco conscious option, there is no denying they’re better suited to some homes than others. 

So, while you weigh up which option is right for your circumstances, remember that upgrading to a more efficient boiler can also help you to save energy and reduce emissions. 

To find out more, get a quote for a new energy-efficient gas boiler now. And while you’re at it, why not get a quote for an air source heat pump too?

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Published 23/04/2024