Why is my boiler making strange noises?

A quick guide on boiler noises and what they mean

boiler making strange noisesIf your boiler starts making strange noises, it could be a sign that something more serious is wrong with it. Even though it might appear to be working perfectly, issues could be lurking.

Noises coming from your machine could mean that it’s about to break down. Therefore, for safety reasons and to ensure you and your family remain warm and with the hot water you need, we advise you to contact your Gas Safe registered engineer.

Our expert engineers know how to deal with noisy boilers. It might turn out to be something or nothing. On the other hand though, it could be a more serious problem that needs immediate attention.

Banging or clunking

Banging and clunking noises coming from your boiler are known as ‘kettling’ noises. They are caused by limescale build-up on the heat exchanger. It can stop the water from flowing properly and may cause the water to boil and steam. This is what creates the noises.

Whilst the likelihood of the boiler blowing up is minimal, especially with new modern boilers, for safety it should be checked by a Gas Safe registered engineer. This type of problem could cause long-term internal boiler damage and greatly reduces your boiler’s efficiency.


A gas boiler that’s making gurgling noises could be doing so because it has air in the system. Alternatively, it could be due to a frozen condensate pipe. The engineer will thaw out the pipe if this is the cause. Gurgling noises can also occur if there’s a blockage, or if gunk has settled in the bottom of the boiler.

Whistling noises in your boiler could also be an issue with kettling or trapped air in the system, or because of loss of water pressure, or a blockage.

If trapped air is causing the whistling noises, an engineer will simply release the trapped air and find out what caused the problem and make repairs.

If your boiler is making a gurgling, banging, clunking, or whistling noise, call the experts on 0800 311 8990. Warm.co.uk will find you an engineer to deal with the problem quickly and efficiently. Don’t simply ignore boiler noises; get them fixed as quickly as possible.