When it comes to modern heating, there’s one option that probably comes to mind: an air-to-water heat pump. It may sound technical, but the results could be more efficient than older heating systems at keeping your home at a comfy temperature.
A report funded by the UK government found that air source heat pumps were three times more efficient than gas boilers and worked in cold weather conditions.1 Read on to find out how this smart heating system works and what it could do for your household.
Air-to-water and air-to-air heat pumps explained.
You’ve probably heard of an air source heat pump? In its broadest sense, it’s a system that absorbs heat from the outside air. There are two main types: air-to-water and air-to-air. Both options extract warmth from the air, even in the chilly British winter! It’s how they deliver that heat that differs.
Air-to-water heat pump.
Let’s start with the most popular option – an air-to-water heat pump (which is what we offer). An air-to-water heat pump takes that warm air and transfers it to your home's wet central heating system.
It basically heats the water that circulates through your radiators or underfloor heating. However, it can also provide hot water for your taps, bath, and shower. See it as a potential replacement for your traditional gas or oil boiler. The only significant difference is that you'll need a water cylinder for your hot water. Plus, you may also need to upgrade some radiators to really boost energy efficiency.
Air-to-air heat pump.
Then there’s an air-to-air heat pump. You could liken the process more to an air conditioning unit. This system extracts heat from the outside air and blows warm air directly through the fans in your room.
While air-to-air heat pumps are great for heating individual spaces, and can even provide cooling on sweltering summer days, they don’t usually heat your domestic hot water. So, you'd need a separate system for that. This type of heat pump is often better suited to smaller properties. Alternatively, they can be an extra heating source rather than a whole-home solution.
Ground source heat pump.
There’s also a ground source heat pump, which works by extracting heat from the ground below. This type of system relies on a network of pipes buried beneath your garden. These pipes collect heat from the soil. The temperature underground is generally more stable than above, so a ground source heat pump could be more energy efficient year-round. Find out more about ground source systems.
Check out our air source heat pump collection, we specialise in air-to-water systems.
The clever mechanics of an air-to-water heat pump.
An air-to-water heat pump operates on the same principle as your fridge – just reverse it! Instead of pushing heat out, it pulls it in. Now, we'll break down how this smart system warms your home:
Grabs heat from the air. The unit sits quietly outside your home and draws in air from its surroundings. Inside, there’s a special refrigerant liquid. Even in super chilly temperatures, there's still heat energy in the air, and this refrigerant absorbs that low-grade warmth. This is the "heat pumps air" part.
Boosts heat. Once the refrigerant has absorbed enough heat, it warms up and transforms into a gas. The gas goes into a compressor, which – you’ve guessed it – compresses the gas. Did you know that compressing a gas significantly increases its pressure? As a result, it also raises the temperature significantly.
Transfers heat to water. Now the gas is super hot, it flows into a heat exchanger. Then, it transfers the heat to the water in your central heating system and your hot water cylinder. This completes the "air to water" process, leaving you with warm water in your radiators and hot taps.
And repeat… After transferring heat, the gas cools down again and condenses back into a liquid. Then, it flows through an expansion valve, lowering pressure and temperature even further. Finally, it’s ready to absorb more heat from the outside air and start the cycle all over again. This clever, continuous cycle is what an air-to-water heat pump is all about.
Could an air-to-water heat pump benefit your home?
An air-to-water heat pump isn't just a new heating system; it's an upgrade that could benefit your home for years to come.
Greater energy efficiency around your home.
Heat pumps are highly regarded for their efficiency. The reason for this is because they're simply moving existing heat, and not generating it by burning fuel. This means that an air-to-water heat pump could be more cost-effective than an older, less efficient heating system (think electric panel heating). However, you’ll need to take into account fuel prices and factors like home insulation.
Improve your carbon footprint.
For many UK homeowners, one of the biggest drivers toward heat pumps is the environmental impact. An air-to-water heat pump could significantly reduce your home's carbon emissions because it doesn’t burn fossil fuels. This is particularly important as the UK electricity grid continues to decarbonise and turn to more renewable energy sources.
Enjoy consistent, cosy warmth.
Unlike boilers that usually fire up intermittently, a heat pump provides a steady lower-level heat. This steadiness can lead to a more consistent, comfy temperature around your home. And another thing. Those hot and cold spots you can sometimes experience with traditional heating are less of an issue with a heat pump, But again, your home’s insulation and other factors need to be taken into account too.
Hone your energy use.
As the UK gradually moves away from fossil fuels, heat pumps are a cornerstone of this transition. Investing in an air-to-water heat pump now has the potential to future-proof your home. Aligning with national energy goals could make your property more desirable for buyers seeking out greener homes. Plus, with ongoing government support like the Boiler Upgrade Scheme (BUS)2, perhaps now is a good time to make the switch.
How much does an air-to-water heat pump cost?
It’s true, the upfront cost of installing an air-to-water heat pump can be higher than a traditional boiler. But think of it as a long-term investment that’ll help improve your carbon footprint. In the UK, the typical cost for an air source heat pump installation can range from £8,000 to £15,0003, depending on your property size and requirements.
You could be eligible for government support.
But there’s good news – government support is available! The government's Boiler Upgrade Scheme2 offers eligible homeowners in England and Wales a grant of £7,500 towards the cost and installation of an air source heat pump. Eligibility usually requires you to own the property, be replacing a fossil fuel system, and have a valid Energy Performance Certificate (EPC). Learn more about the Boiler Upgrade Scheme.
Important points to consider.
It's also worth noting what you'll typically need for an air-to-water heat pump system:
An outdoor unit. This is the part that extracts heat from the air. It needs to be outside your property, usually on the ground with sufficient space for airflow.
An indoor hot water cylinder. Unlike some combi boilers, air-to-water heat pumps need a hot water cylinder. This is so it can store heated water for your taps and showers. We'll help assess the right size for your home.
Good home insulation. For any heating system to work optimally, good insulation is key. Heat pumps work best in well-insulated homes, as they provide heat consistently at a lower temperature. Ensuring your loft and walls are well-insulated will help your heat pump run as efficiently as possible, keeping your home warm and your bills down.
We can help you choose the right air-to-water heat pump.
Currently, all our heat pumps are air-to-water systems, so we have several models to choose from. We can also help you understand the total cost, taking into account any grants you're eligible for, after a detailed home survey.
Ready to explore your options and get a clearer picture of your specific home needs? Find out more about our air source heat pumps and how to buy a heat pump.
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