Why is my boiler so noisy

It is perfectly normal for a boiler to make noise – in fact, it is to be expected. Noises from your boiler can show that everything is working as it should, but there are certain sounds that can indicate that there may be a problem, and your boiler may need to be checked by an engineer.

Boiler repair


The most common boiler noise is known as ‘kettling’. Why is it known as that? Well, because your boiler sounds like someone is making a cuppa: bubbling, whistling, or popping noises, like a kettle – hence the name.

There are a couple of possibilities as to why your boiler is making this noise:

  • Leaks – Is there a leak? There may be a leak in the boiler itself or even somewhere in the pipework. Check the pipes around your radiators – listen out for any dripping noises too. This can also be an indication that there is a leak somewhere in your heating system. Leaks need to be sorted quickly, as water can damage the electrics within your appliance or the surrounding walls and floor in your home.
  • Limescale – If you live in a hard water area, you are more likely to encounter limescale in your pipes – this is because the water has higher levels of calcium which can lead to a build-up of deposits in your pipework. Limescale can cause blockages in your pipes, which can lead to cold spots in your radiators; or the heat exchanger in your boiler, leading to a risk of overheating and produce that ‘kettle’ sound. Pay attention to your boiler’s thermostat – if it is faulty, then this can also lead to your appliance overheating.


As we said, some noise is normal for a boiler, so what if you turn your heating on and there’s silence? Failure to hear that spark can suggest that there is a problem with your boiler’s ignition. This issue will require a gas engineer – the problem may not just be with your appliance, but there could be issues with the gas mains.


Hammering noises could be alarming. No need to panic, your boiler may be just low on pressure – just check the pressure gauge. Low pressure could be the result of a leak, however, if all seems fine, you may just need to top up the pressure which you can do yourself.


Gurgling noises can mean that there is air trapped in the system, most likely your radiators. Trapped air in your radiators means that they do not heat up evenly, and you’ll find cold patches when you touch them. Bleeding your radiators can be messy, but not difficult – use a radiator key to release that air and get the water flowing again.

Vibrations and Whooshing

If your boiler has started to vibrate or make ‘whooshing’ sounds, then you may have a blockage in the flue. Your flue is important, as this blows out condensation and gases – and because they are on the outside of the house, they can get clogged up with leaves, and other debris.

Not all noises mean the end of life for your boiler, but if in doubt you should always contact a heating engineer.  They will be able to tell you if it is a simple repair, or if you need to speak to someone about a new boiler.