If your boiler is making a banging noise then it could be due to kettling usually caused by limescale or debris within the system.
Kettling is caused by a build-up of sludge in the heat exchanger, this build-up occurs more frequently with older exchangers and in areas with hard water. When water flow through the heat exchanger has slowed or become completely blocked the kettling process causes the water to boil and causes steam. If you can hear the sound steam produces in the system this noise may be another indication of kettling as the cause.
The loud banging caused by kettling can feel like the boiler is going to explode but rest assured kettling will not cause an exploding boiler. The issue however is not an easy DIY fix and we recommend finding a local engineer to confirm a build-up in your system.
Can you hear the pipes banging when you turn the hot tap on? Overheating could be the cause, check your thermostat by turning the boiler off and let the system cool down. Once the system has cooled down turn it back on again and turn up the thermostat and you should hear it click. If you don’t hear a click then we recommend now is the time to call the professionals and find your local Gas Safe Registered engineer.
Sometimes banging pipes are due to pipework not being secured properly under the floor if you’ve always heard rattling noises, then this may be the reason. This can make them rattle around when water is flowing through them.
Call a Professional
There are many different noises that your boiler can make such as humming, banging, ticking,buzzing, vibrating and while some of them can seem worrying at first, most can easily be fixed. If you are unsure about any noise your heating system is making, the safest thing to do is call a professional.