Heat pump FAQ: How loud is a heat pump?

If you’re thinking about installing a heat pump, one of the most common questions is: how much noise will it make?It’s a fair concern – especially if you’re investing in long-term comfort and want to make sure your home stays peaceful, indoors and out.

Here’s what to expect – and how to ensure your system runs as quietly as possible.

How loud is an air source heat pump?

Quiet, unobtrusive – and even quieter with proper installation

Modern air source heat pumps (ASHPs) are designed to operate with minimal disruption. Most produce sound levels between 40 and 60 decibels (dB) – depending on the model and how hard it’s working.

To put that into context:

• Around 40 dB – comparable to a quiet fridge
• Around 50–60 dB – similar to an air conditioning unit
• Above 70 dB – would be equivalent to a washing machine (well above typical ASHPs)

“Think of a heat pump like your fridge – only working in reverse. It’s familiar technology, just used differently.”

Geordie Stewart, Retrofit Scheme Manager

Most of the sound comes from the external unit, so when installed correctly, you’re unlikely to hear it from inside your home – or cause any disturbance to neighbours.

What about ground source heat pumps?

Yes – and barely noticeable

Ground source heat pumps (GSHPs) are even quieter. Because they draw heat from underground and don’t require a fan unit outside, they typically operate at 30 to 40 dB – quieter than a whisper.

If sound is a major factor in your decision, and you have the space for one, a ground source system could be a great fit.

What do the regulations say about heat pump noise?

In the UK, Permitted Development Rights allow most air source heat pumps to be installed without planning permission – provided they meet strict noise limits.

• The key threshold is 42 dB at the boundary of the nearest neighbouring home
• Recent updates to planning rules in England have relaxed restrictions even further – making installation easier while keeping systems neighbour-friendly

A good installer will make sure your system meets all the necessary requirements.

Tips for a quieter installation

To ensure your heat pump runs as quietly as possible:

• Choose the right location – place the external unit away from windows, corners, or enclosed spaces that could reflect sound
• Use a professional installer – mounting and insulation matter. Expert fitting minimises vibration and ensures a smoother performance
• Schedule regular maintenance – clean fans, well-lubricated parts, and regular check-ups help keep noise levels low

Is a heat pump right for your home?

Today’s heat pumps are designed for comfort, efficiency – and quiet operation. But like any energy system, they work best when installed as part of a joined-up plan.

At Cosy Homes Oxfordshire, we offer a Whole House Plan that assesses your home’s layout, insulation, ventilation, and energy use – helping you decide whether a heat pump is right for you, and how to make the most of it.

Getting started

We’re here to help you make confident decisions about your home. Call our team on 0330 223 2742 (Monday to Friday), or send us a message to start your journey to a warmer, quieter, and more energy-efficient home.

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