Find out more about the difference between heat pumps and conventional boilers

Heating our homes efficiently has become a hot topic – not least of all because of the rising costs of energy bills but because the climate emergency compels more of us to act.

By 2025, the UK is planning to have begun transitioning out of old, conventional-style heating systems by banning gas boilers in newly build homes. Catering to this fresh demand for renewable energy sources, manufacturers have adapted with hydrogen boilers, hybrid systems and heat pumps to choose from, to name just a few.

But what are the differences between heat pumps and conventional boilers? We’ll be investigating this question, giving you all the pros as well as the cons when it comes to making the switch.


Why are conventional boilers and heat pumps being compared?

Conventional boilers have reigned supreme as a primary means of domestic heating over the course of the past century. That is, until heat pumps came along.

Gas boilers have come under scrutiny as more and more people are making adaptations to their homes and livelihoods to better support the environmental effort. Heat pumps have risen to attention as a result since they do not rely on a fossil fuel to work and they therefore reduce our carbon footprint.

However, heat pumps are complex. They come in many different forms – from ground source and water source to air source and even air-to-water source. The main two types to familiarise yourself with are air and ground source heat pumps.

Air source heat pumps are the most common in the UK and look similar to an air conditioning unit. Ground source heat pumps, meanwhile, require deep piping underground. Both essentially work to transfer heat from one place, either the air of the ground, to another place (our homes) by using a circuit of refrigerant driven by an electric powered compressor.

But now, let’s compare boilers to heat pumps.


Efficiency and emissions

When it comes to maximum efficiency and reduced emissions, heat pumps take the crown.

Gas boilers need gas as fuel to heat the water which runs through the pipes and radiators in our homes. Some portion of heat always manages to escape – on average, the equivalent of 6p per every £1 spent. Plus, they emit carbon dioxide into the atmosphere.

Heat pumps do not need a fossil energy source to work. They simply disperse warmth into cooler areas, rather than generating heat. As a result, the home is kept at an optimal temperature all year round and can provide up to 3 to 4 times more heat than the amount of energy it consumes.

However, the efficiency still hinges on the existing insulation of your home and the individual COP (Coefficient of Performance) rating of the heat pump. Some only have a COP of 3, which fails to meet the efficiency of a conventional boiler while others require underfloor heating or oversized radiators to work efficiently.


Operating costs

The recent fuel crisis is having significant consequences on how we consume energy with gas continuing to creep higher and higher in price. The good news is that you can reduce, if not completely axe, your gas usage with a heat pump.

A study by The Energy Saving Trust found that replacing an old gas boiler with an air source heat pump in a four-bedroom detached home can accumulate savings of between £375 to £425 per year on utility bills.

However, the downside is that electricity isn’t cheap either but at least there are Government schemes to help you: the Renewable Heat Incentive sees homeowners awarded a small sum for heating their homes renewably, and a new Clean Heat Grant is on the way for April 2022 to help with upfront costs.

If you’re able to power your electricity through solar panels, you can also massively reduce your bills and operating costs.


Cost to install

While a heat pump could potentially save you money in the long-run through reduced energy bills, installation costs can run significantly higher than that of a gas boiler.

While heat pumps are earmarked for the future with the Government’s lofty plans to install 600,000 new pumps every year by 2028, many homeowners are deterred by the installation costs.

Gas boilers cost anywhere between £1,000 to £3,500 to buy and install, depending on boiler type, manufacturer and model.

Meanwhile, heat pumps can cost upwards of £10,000. Ground source heat pumps almost double this at around £18,000, which is expected due to the demands of the installation process.


Time taken to heat the home

With a conventional boiler, you’re more likely to experience two extremes in room temperature and the time taken to heat your home. When the temperature plummets outside, our homes become cold until we race to crank up the heating. In a few hours’ time, the house should be well heated, though each room might vary in temperature depending on the size and efficiency of the radiators in each area.

This is vastly different from a heat pump which doesn’t rush to provide heat at the push of a button or tweak of a thermostat. Instead, it keeps the house warm at a comfortable temperature and distributes the heat evenly into each room.

So, while the heat pump won’t see your house plummeting to extremely cold temperatures, it also doesn’t deliver a sudden burst of concentrated heat.


Life Span

A key advantage to heat pumps is that they boast an impressive life span, far outlasting that of a conventional boiler. While a boiler might expect to be replaced every 10 to 15 years, heat pumps have a longevity of 20 to 30 years, providing they are maintained properly.


Space needed for installation

Some boilers take up a cupboard-size space in our homes, and can be considered unsightly boxes.

By contrast, heat pumps live outside and out of mind. However, this also means you need some outdoor space to accommodate it with ground source heat pumps needing a large space to fit its complex web of underground pipes in a borehole – but then once it’s done, you can cover the land.



Both boilers and heat pumps need looking after, and should be serviced once a year by a professional to check their longevity, safety and reliability.


All-in-all, switching to a heat pump is a big decision but an important one if you’re serious about cutting down your energy bills and carbon footprint in the process. If they’re good enough to function in sub-zero temperatures in countries such as Norway, Sweden and Denmark, there’s no reason why they won’t function to great success here in the UK and for your home, too.


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Written by:

Rob Chevasco, Sales Manager, Shrieve Products International Ltd.