The Best Air Source Heat Pumps 2023

✔ The Grant Aerona³ R32 is the best air source heat pump overall

✔ The LG Therma V R32 Monobloc still works when it’s -25°C outside

✔ An air source heat pump typically cuts your carbon footprint by 44%

If you're looking to buy an air source heat pump, you'll find a huge number of options in every category. It can be overwhelming.

Fortunately, we can help. Our team of four experts have spent 29 hours analysing 22 top heat pumps from 19 industry-leading manufacturers, judging them on seven factors including cost, efficiency, power, and warranty length.

If you want to harness the power of a heat pump, just fill in this form and our trusted installers will be in touch.

Best for cost: Grant Aerona³ R32

The best air source heat pump on the market right now is the Grant Aerona³ R32. And luckily for all of us, it’s also the best value model around, at just £6,018 before installation.

Grant’s product is the cheapest high-quality heat pump around, yet its peak efficiency rating is still an astounding 479%, meaning it produces 4.79 units of heat for every unit of electricity it uses.

Most heat pumps’ peak efficiency ratings fall between 300% and 400%, making this a special machine – and it’s the lightest on our list too, weighing in at a svelte 120kg.

The average price of a heat pump is between £7,000 and £13,000, so this a bargain.

If you're interested in the best heat pump around – or any of the other excellent contenders on this list – just pop your details in this short form, and talk directly to qualified heat pump suppliers near you.

Grant Aerona³ R32: pros & cons

Best for efficiency: Dimplex System H6 HTi70

If you have a medium-sized house, Dimplex's latest market-leading product is a must-have.

With a table-topping efficiency rating of 572%, this machine is five times better than a gas boiler, on average.

At its best, it's also significantly better than the average air source heat pump, which usually peaks at 350%.

Its maximum output of 8kW is low compared to the other top heat pumps out there, but will be more than enough for most homes.

Dimplex System H6 HTi70: pros & cons

Best for cold climates: LG Therma V R32 Monobloc

If you live in below-freezing conditions, it’s a massive relief not to have to go outside and fix the heating when it’s dangerously cold.

Fortunately, even though heat pumps work by absorbing warmth from the air outside, LG’s best model is still able to function happily at temperatures as low as -25°C.

Considering the industry average is -10°C, that's extremely impressive.

So when the snow and icy winds sweep in at full power, you can wrap up with a hot drink, safe and comfortable in the knowledge that your heat pump will keep you warm.

LG Therma V R32 Monobloc: pros & cons

Best for swimming pools: HydroPro ECO 12

With a maximum power of 12 kW and a hugely impressive peak efficiency rating of 480%, this heat pump from the appropriately named HydroPro is the perfect way to keep your pool water nice and warm.

After all, heat pumps take warmth from the air to heat your water – so why not your pool water?

A swimming pool heat pump usually costs around £3,500, but with the HydroPro, you can save money and ensure that getting into your pool is an enjoyable experience – not a chilly chore.

HydroPro ECO 12: pros & cons

Best for power: Vaillant flexoTHERM 400v

This behemoth of a machine can provide you with heating and hot water in the blink of an eye, reaching temperatures of 65°C in no time.

Considering a hot shower comes in around 40°C to 45°C, that should be more than enough.

Vaillant’s model has a peak power of 19 kW, compared to the industry average of 5 kW – so if you have a particularly large house, this is the heat pump for you.

It also has a high efficiency rate, meaning it’ll still heavily reduce your carbon footprint, despite using more energy than most heat pumps.

Vaillant flexoTHERM 400v: pros & cons

Best for warranty: MasterTherm UK BoxAir Inverter

This Welsh firm has positioned itself excellently for the ongoing air source heat pump revolution.

MasterTherm offers a model that’s typically five times as efficient as a typical gas boiler for an extremely reasonable price.

Throw in an unbeatable seven-year warranty – with no strings attached – when the industry average is five, and enough power to comfortably heat the average three-bedroom house, and you’ve got an excellent machine you can rely on.

MasterTherm UK BoxAir Inverter: pros & cons

Best for high temperature: Daikin Altherma 3 H HT

Thanks to this Japanese company, UK homes can now buy heat pumps that supply water at temperatures up to 70°C – the same level as gas boilers.

This is a whole level above the temperature most heat pumps can provide, which hovers around 50-55°C.

You can choose between Daikin's wall-mounted unit with a separate hot water cylinder (which many gas boiler owners will already have), or a single, floor-standing unit with an integrated hot water cylinder.

This heat pump is more expensive than some machines, but it's much simpler to install – and you won't have to replace your radiators or get more insulation, which can be expensive.

Daikin Altherma 3 H HT: pros & cons

One to watch: Ventive Home-B

One day in the near future, a large box called Home-B could be the only system you need to supply heat, hot water, and ventilation to your property.

Ventive's creation ventilates your home, then uses that air to provide you with heat and hot water – plus it comes with a thermal battery that allows you to only use electricity when it's cheap.

Home-B, which is partly supported by government funding, has already been trialled in Nottingham. Now, a factory in Worcestershire is creating thousands of these machines for homes all over the country.

How did we choose the best air source heat pumps?

Our team of four researchers spent 29 hours investigating the market to find the top models currently available, before narrowing it down to the seven best air source heat pumps.

We recorded all these heat pumps' attributes, then focused on the most important factors in making our final decisions.

These factors were the cost, efficiency, product warranty, maximum power, minimum temperature required, and weight.

And if you're worried about heat pumps being an eyesore or making a lot of noise, don't be. All the machines on this list are quiet and relatively small.

1. Cost

You want an investment that feels like a bargain, even when you're spending thousands of pounds.

Heat pumps can cost anywhere between £1,000 and £10,000 before installation, but we focused on finding machines that can secure you the best value for money.

2. Efficiency

This refers to the number of heat units a heat pump can produce from one unit of energy.

The average model can generate 3-4 kWh of heat from 1 kWh of electricity, but as you can see from this list, we looked for machines that go above and beyond the average.

3. Warranty

When you're making a large investment, you want to be protected if it breaks down, for as many years as possible.

Five years is the standard product warranty, but you can attain better warranties now, with seven-year contracts fast becoming the norm.

4. Power

We wanted to find machines that were powerful enough to provide enough heat for any household.

That's why all the heat pumps in this list are far above the industry average – though they also come in smaller sizes.

5. Minimum operating temperature

Air source heat pumps are incredibly good at finding warmth in the air, even when it's way below freezing outside.

As climate change creates a world with increasingly extreme temperatures, it's best to be prepared for the mercury to drop.

6. Weight

Most top heat pumps are between 100 and 150 kg. This is a reasonable size for a home, allowing you to get heat without defacing your facade.

However, some weigh 400 kg or more – as much as five full-grown men – which worked against those machines in our rankings.

Next steps

In May 2022, the Boiler Upgrade Scheme came into effect.

The grant subsidises air source heat pump installation by £7,500, meaning you’ll be able to get one installed much more affordably.

When you consider that heat pumps typically last 20 years – twice as long as the average gas boiler – you’ll be cutting your carbon footprint for years to come.

It won't even cost you any more than having a gas boiler by the end of its 20-year lifespan. In fact, you'll save money overall.

And if you pop some information into our quick quote tool, we’ll put you in touch with our trusted heat pump installers.

Best heat pumps: FAQs