You are currently viewing Is A Noisy Boiler Dangerous?

Is A Noisy Boiler Dangerous?

Our boilers are something we don’t usually think about – not until something goes wrong. And when it does go wrong, it can go really wrong. So making sure you’re aware of what a working boiler looks, and sounds like, is crucial.

So, is a noisy boiler dangerous? Unfortunately, the answer isn’t as cut and dry as it may seem. Generally, a noisy boiler doesn’t mean it’s dangerous, but it could mean something is wrong. Knowing the make and model of your boiler will help immensely when it comes to diagnosing weird sounds. There are, however, a few common noise complaints that we can help you with.

Potentially Dangerous Noises From Your Boiler


The first of the most common noises is a vibrating sound. There are a couple of things that can cause this; a build-up of sludge and grime, a malfunctioning or loose pump, or an incorrect setting is currently applied to the pump.


Older cast iron boilers seem to bang more than other, newer models. The most common cause of a banging sound is your boiler kettling. Kettling is a build-up of limescale on the heat exchanger.


However, it doesn’t have to be a noise as dramatic as banging to be kettling. Sometimes if your boiler is kettling, you’ll hear a tapping noise instead. The build-up of limescale will restrict the water flow, causing the water to boil and create steam inside.


Similar to a foghorn or far away plane, a droning noise is a likely sign that the boiler pump is about to fail. It can happen really easily – a mechanical failure or debris getting caught is sometimes all it takes.

Note that all of the above sounds are somewhat dangerous and problematic noises to be hearing from your boiler. If you hear any of these noises, you should call a gas safe register heating engineer to come and check it out as soon as possible.

Gas boiler control panel close up image


If you hear a rattling noise coming from your boiler, the chances are that it’s loose objects hitting each other, air in the pipework, a faulty pipe, or a loose valve.


For a humming noise, there are also a few common issues that could be causing it. An issue with the fan, a washer needing replacement, the pressure needs readjusting, or the heating element needs tightening.

Kettle-Esque Noises

A boiling kettle is a distinctive noise and usually signals that it’s time for a cuppa. But if you’re hearing it from your boiler, that’s not always a good sign. Kettle noises are generally a sign that there is kettling going on inside, or there is air trapped somewhere inside the system.

Dripping or Gurgling

A dripping or gurgling sound can potentially be caused by trapped air inside the boiler. This can decrease the effectiveness of the boiler and it might not work at its full capacity.

> The last four noises aren’t dangerous in and of themselves, but they could become dangerous if left alone. You can try to fix these problems yourself by bleeding the radiators or adjusting the pressure.

If you’re unsure about any noise your boiler is making, or don’t feel confident enough to try and fix it yourself – call a professional! A qualified heating engineer will identify and fix the problem in no time, saving you the trouble of needing a new boiler!

We hope you like reading the post and found it to be informative. More boiler and central heating tips and advice can be found on our blog. If you have any questions, please get in touch with us on 07771 956641, our friendly team is always happy to help you.