How to find the cause of a noisy boiler

Although, it’s normal to hear some noise coming from your boiler, a continuously loud boiler is usually an indicator of a problem. Unfortunately, an increasingly noisy boiler generally has a fault that needs to be repaired. If this is ignored, then it could potentially develop into a more serious issue in the future.

There are several different reasons why a boiler might make noises. Quite often, the cause of the fault can be discovered by the type of noise coming from the boiler.

The most common cause of a gurgling boiler is when too much air gets trapped in the system. This can act as a blockage, stopping the hot water from travelling around the system properly. In turn, the radiators will stay cold in places, preventing certain rooms from heating up. Luckily, this issue can be solved easily by bleeding the radiators around your home.

A humming boiler will likely be caused by high boiler pressure. If your boiler is not set at an appropriate pressure, it won’t run efficiently. You should check the guidelines for your specific boiler, although when considering most modern models, the ideal pressure is around 1.5 bars.

If the pressure is over 2 bars, or even in the red zone, then you can lower it by bleeding the radiators. In the instance that the boiler pressure matches the manufacturer’s guidelines, the humming could be caused by the pump being set to a high speed. However, before adjusting the speed setting, you should contact a heating engineer first, to ensure that the pump isn’t set high for a reason.

A whistling noise is caused by an issue, known as kittling, which is when limescale builds up on the heat exchanger. As you can’t solve this issue yourself, you will need a heating engineer to perform a powerflush, which will clear away the limescale.

A clever way of preventing this build-up of sludge is to install a magnetic filter. This will stop your heating system from kittling, making it run more efficiently in the process.

Your boiler might be vibrating for various reasons. If your boiler was installed recently, then it could have been fitted poorly. To fix this, a heating engineer will be able to tighten the necessary brackets. Although, these vibrations could also be caused by loose parts or open components that need closing.

Like vibrating noises, tapping noises can be a sign of loose or poorly fitted parts. To stop these noises the part will need to be tightened. Another potential cause of tapping noises is a build-up of sludge and limescale around the heat exchanger.

Banging noises from your boiler could be yet another sign of trapped air in your system. Like other issues, you should be able to solve the problem by bleeding the radiators. If not, large bubbles could be popping because of a blocked heat exchanger.

A dripping noise is a definitive indicator that there is a leak somewhere around the heating system. You should seek the help of a heating engineer, as a leak will only get worse if left.