How noisy are heat pumps?

20 May 2024 | OVO

There’s lots to consider when getting a heat pump. You’ll need to think about what type to get, who’ll install it, and what the running costs will be.

Some recent headlines have claimed that heat pumps are too loud for many UK homes.1 So you might also be considering how noisy your new heating system will be. It’s a common fear that a heat pump will be loud and disturb you and your neighbours. But how likely is this really?

How loud is an air source heat pump?

Early air source heat pumps were noisy, but technology has evolved – resulting in quieter, more efficient modern heat pumps. When on, they make between 40-60 decibels of noise on average, at a distance of 1 metre. This is classed as a low to average level. It’s somewhere between a quiet library and a dishwasher, and is similar to a microwave.

As a comparison, a modern combi boiler also makes a noise level between 40-60 decibels when it’s on. But a boiler is usually inside, while a heat pump is outside – so you’ll be less likely to notice noise.

Many heat pumps are certified by Quiet Mark, an independent programme linked to the UK Noise Abatement Society. Heat pumps with the mark include models from Vaillant, Samsung and Daikin.

What does a heat pump sound like?

A heat pump makes a low whirring or humming sound when it’s running.

A survey of heat pump owners by noise experts found most people surveyed didn’t notice the sound. People said they’d be more likely to hear dogs barking and nearby traffic over the sound of a heat pump. You can hold a conversation next to a heat pump without having to raise your voice.

Why does a heat pump make noise?

Heat pumps make noise when the fan pulls air into the compressor on the outdoor unit. The level of noise depends on what the heat pump is doing. The outdoor unit can be louder in colder weather, when it’s working harder to defrost, or heat water.

When the fan isn’t on, the heat pump will be almost silent. If your heat pump is installed correctly by a good installer, you shouldn’t be able to hear it inside.

When you get a heat pump through OVO, it’ll be installed by Heat Geek’s national network of award-winning installers. They’re experts in high quality heat pump installations.

OVO customers in kitchen with heat pump outside

Can you hear a heat pump inside your house?

If your heat pump has an indoor unit, it won’t make much noise at all as it’ll only contain valves and pumps. The outdoor unit will be unlikely to disturb you when you’re inside, even if the windows are open.

If your heat pump is making a loud noise that you can hear indoors, it might be a sign of an issue. You can get in touch with your installer who'll take a look and see if any maintenance is needed.

Will my heat pump disturb my neighbours? What are the regulations on heat pump noise?

Most installers will try to put the heat pump away from windows and your neighbours to reduce noise. Planning law means noise from your heat pump must be under 42 decibels halfway between your heat pump and your neighbour’s home. A good installer will make sure your heat pump won’t be a nuisance to neighbours.

If you get a heat pump installed through OVO, your installer will do a design consultation to see where your heat pump will go. Your installer will also make sure your heat pump passes strict noise regulations. They’ll do some calculations with you, and make sure your installation is within allowed noise levels.

Interested in saying goodbye to gas? Get your heat pump through OVO.

You can now get your heat pump installed through our exclusive partnership with Heat Geek.

You’ll also unlock our free add-on, Heat Pump Plus, which gives you a better electricity rate for powering your heat pump. It means you can save up to £210 a year on your heating bills compared to a gas boiler.2

Find out more and register your interest

Sources and references:


2 Savings of £210 are based on the following comparison: a gas boiler running at 90% efficiency (as per the national average for A-rated boilers) with an annual consumption of 11,500 kWh at 5.75p/kWh, and 77% of consumption used for heating and hot water, versus an air source heat pump with a Seasonal Coefficient of Performance (or efficiency rating) of 4 and an annual consumption of 1,992 kWh at 15p/kWh with the Heat Pump Plus add-on. Rates correct as of May 2024.