Unusual noises from your boiler
3 min readPublished on 15 September 2026
A heating system always makes some noise. When that noise changes clearly or becomes intrusive, it is worth having the system looked at. A sound on its own is never enough for a firm diagnosis; that needs an inspection.
Ticking
Ticking often comes from pipework expanding and contracting, but it can also point to fixings that are pinched or to debris in the system.
Gurgling
Gurgling usually suggests air or debris in the system, or pressure that is too low. Note what the gauge reads when you hear it.
Humming or vibrating
A hum or vibration often comes from a moving part, or from vibration carried into the house through fixings. Have it assessed if it persists.
A loud ignition
If you hear a bang or thud as the boiler fires up, stop using it and have the appliance checked. That is not a noise to carry on with.
When to switch the boiler off
After a loud ignition, with unusual noises combined with a smell of gas, or with a visible leak: switch the boiler off and get help.
Have it assessed when
- the noise is new or clearly getting worse;
- the noise comes with pressure loss or an error code;
- you hear a bang as the boiler fires up;
- you cannot work out where the noise comes from.
Want the noise checked?
Book a service and tell us in the request which noise you hear and when.
More from our advice pages
- No hot water: what you can safely checkSafe checks when the taps run cold, and how to tell a hot-water problem from a heating problem.
- Your boiler keeps losing pressure: what it meansWhat pressure loss means, how to handle topping up safely, and when repeated topping up is a warning sign.
- An error code on your boiler: what next?How to record an error code, why the manual comes first, and what to send with a fault report.