Last Updated on 23rd August 2022

Why is my boiler making loud noises

Your boiler making loud noises is usually a sign of some kind of fault within the central heating system and could be time to think about how long your boiler can last.

It is important to investigate these noises, as ignoring boiler problems can be expensive and dangerous.

Luckily, the specific noises a boiler makes can help us to find the cause of the fault, so we have put together a guide to the noises your boiler might make – and the faults of which they might be a symptom.


So called because it sounds a lot like a kettle boiling, kettling usually indicates sludge and limescale build up.

This is a common problem and is often easily solved.

Severe cases will require an engineer to perform a powerflush to get all of the built up waste out of the system.


Dripping sounds usually indicate some sort of leak, most often caused by wear but sometimes caused by excess pressure within the system.

Older boilers are particularly prone to this.

This fault requires a qualified engineer to replace damaged components and can be an expensive problem to solve.

My Boiler is Making a Gurgling Noise

When you hear gurgling from within your central heating system it is most likely trapped air. This is usually remedied by bleeding the radiators – a task you can easily carry out yourself.

You can verify that this is the issue by checking the radiators. If there are cold patches or it is very slow to heat, they need to be bled.

If bleeding the radiators does not fix the problem, a professional will need to diagnose the problem as it could be more serious.


Tapping sounds usually indicate either limescale build up or an incorrectly fitted part.

If you have had any parts replaced recently, it’s probably the latter.

If not, it might be worth looking into a powerflush service to clear out the limescale, which can be a particular problem in hard water areas.

Banging Noise

Banging sounds are usually due to worn or poorly fitted pipes.

The pipes are under stress constantly from temperature and pressure shifts, which can lead to damage and loud noises when the pipes are not properly fitted.

You will likely need an engineer to come out and refit or replace the pipes in question.

Why Is My Boiler Making Humming Noises?

A boiler operating normally should emit a relatively quiet humming sound, but a noticeable increase in the volume of this humming might indicate problems with the heating element.

This is not a problem you can handle yourself, so you must contact a qualified engineer to come and repair or replace the affected components.


These loud noises coming from your boiler and central heating system can be indicative of serious faults, but it is often worth it to just check the general health of your boiler.

Check the pressure, the radiators and any warning or error messages on the digital display if there is one. Rectifying those problems might solve your issues altogether.

But you should never carry out work on your own boiler. For any problem that might be the result of a fault, poorly fitted parts or wear of existing parts, you will need a qualified engineer to ensure that your boiler is brought back to working order in a safe and effective manner.