Why is my boiler making strange noises?

Boilers are one of those appliances that we heavily rely on especially during the winter. And a minor fault can disrupt our daily lives. So, it is of the utmost importance that you should maintain your boiler in its best shape. 

Now, a boiler can experience different types of faults but one of the most common issues is a boiler making strange noises. Usually, a boiler will make noise when it is working. But how do you know that a regular noise from your boiler has turned into something unusual and is highlighting of a problem? 

We will tell you the most common types of boiler noises and why they occur. If you find that your boiler is making one of the following strange noises, you should call a professional for a boiler repair, as leaving it or trying to deal with it yourself could lead to expensive or fatal issues.

Humming Noise

This type of noise comes from a boiler when the pressure is set too high. The standard boiler pressure is around 1.5 bar. If the pressure reaches above 1.5 bar or in the red zone, your boiler will start making a humming noise. You can get rid of the humming noise by releasing the pressure, which is done by bleeding the radiators. If you need professional help to bleed your radiators, make sure to call a Gas Safe Engineer. 

However, you might find that the boiler pressure is set correctly but it is still humming. Another reason for this could be the pump. The pump will push the hot water in your home into the radiators. If your home has a multiple-speed heating pump and it is set too high, your boiler will make a humming noise. The best thing to do would be to reduce the speed to a lower setting, we advise calling in a professional for this, if you can’t clearly figure out how to do it.

Gurgling Noise

If you hear gurgling noises from your boiler, chances are air is trapped in the system. The trapped air will block the easy flow of hot water in your pipes. Apart from gurgling noise, you might also have cold radiators. You can get rid of this issue easily by bleeding your radiators and getting the trapped air out.  

Vibrating Noise

Is your boiler vibrating? If so, chances are your boiler is not fitted correctly. Loose brackets and internal components can cause a vibrating noise. 

To fix this issue, you can try to tighten the brackets with screwdriver, but if the whole boiler is vibrating then it’s best to give your boiler engineer a call and ask them to fit the brackets and loose components. You may even need to alter the position of the circulating pump. If it continues to vibrate, it may also be an issues with the pump being set too high, in which case the speed will need to be reduced. 

Whistling Noise

If your boiler is making a whistling noise, it is known as kettling. This occurs when limescale or sludge builds up in the heat exchanger of the boiler. The way to fix this issue is by getting a power flush.

You can call a heating engineer for power flushing services so they can remove the limescale and sludge. Another way to tackle this issue is by asking your boiler engineer to fix a magnetic filter that will collect all the limescale before it builds up in the boiler. 

These are the four most common types of noises that your boiler can make. You can also hear tapping, banging, or dripping noises. These noises are also indicative of trapped air, leaking water, or loose components. 

If you are in a predicament where your boiler is making too much noise, you should call a gas-safe /boiler engineer to take a look. Or even worse, if you are avoiding switching your boiler on because it makes a lot of noise, thus making you live in a cold home, you need to call an engineer. You shouldn’t be made to choose between a quiet home and a warm home.  You can get in touch with us at SP Boilers. We have been providing high-quality boiler services such as boiler installations in London and Surrey, for several years.

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