My boiler is making strange noises – Do I need to call an engineer?

My boiler is making strange noises – Do I need to call an engineer?

Posted on April 7, 2021

Most boilers will make noises now and again – But how do you know when that noise means something is wrong?

If your boiler is making a new noise all of a sudden, then it’s a good idea to get a registered Gas Safe engineer to come and take a look.

An increasingly noisy boiler, or one making strange noises you haven’t heard before, is likely to have some kind of fault that if left unrepaired could mean a bigger repair bill or a complete boiler breakdown.

So, let’s look at the types of noises you might hear from your boiler and what they could mean.

My boiler is making a gurgling noise

A gurgling boiler is usually down to too much air being in the system. This can cause a blockage which would stop the hot water from circulating around your heating system properly. A common symptom of this would be cold radiators. If you can hear a gurgling sound and your rooms aren’t heating up effectively then air in the system is the most likely culprit.

This particular problem shouldn’t need an engineer to come out. To release the air from your system, bleed each of your radiators and see if that solves the issue (and the gurgling noise!).

My boiler is making a humming noise

For your boiler to run effectively, it needs to be set to an appropriate pressure. If you can hear a humming noise coming from your boiler then it’s likely that the pressure is set too high.

Your boiler pressure should be set to around 1.5 bar, but always check the specifications in your boiler manual. You can see the pressure of your boiler on the pressure gauge.

If you can hear a humming and your boiler pressure is over 2 or in the red zone, then you will need to relieve this pressure by bleeding the radiators.

If your boiler is humming but the pressure is correct, then the noise could be coming from the pump. Hot water is pushed around your home to the radiators via the pump. If you have a multiple speed central heating pump and it’s set too high, then this could lead to a noisy boiler. There are possible reasons for setting a pump to ‘high’ so before turning the speed setting down, always check with the Gas Safe engineer who installed your boiler.

My boiler is making a whistling noise

You know the sound an old-fashioned kettle makes when it’s boiling? If your boiler is making a sound like this – called kettling – then it could be a build-up of limescale on the heat exchanger. The heat exchanger is where the heat from the gas is transferred to the water that will be circulating to your radiators.

There isn’t a simple fix for this one that you can do yourself, so you will need to call a Gas Safe registered engineer. They will do a power flush which should clean away the limescale and any other bits of debris that could be in the system causing problems.

One way to avoid kettling happening in the first place is to get an engineer to install a magnetic filter, which will collect any limescale and sludge before it builds up and causes problems. It’ll help stop kettling as well as making your boiler more efficient.

Do you live in a hard water area? You can read our blog on how hard water could affect your boiler here.

My boiler is vibrating

A vibrating boiler may be as simple as it not being fitted properly to the wall. If you’ve recently had your boiler installed, then give them a call and ask for Gas Safe engineer to come and tighten the brackets.

A vibrating boiler could also be caused by loose components or parts which will need to be looked at by a Gas Safe engineer.

These issues not the problem? It could be that your central heating pump is set too fast for your home.  Alternatively, the vibrations could be caused by loose parts or components that are open and need closing.

Whilst you may be able to tighten a bracket yourself, if your boiler is persistently vibrating you should call a Gas Safe registered engineer to come and take a look in case it is an internal part.

My boiler is making a tapping sound

A tapping noise is likely to be due to the same issues as vibrating – Poorly fitted or loose parts. In this scenario, the loose part will need to be tightened. This will need a Gas Safe registered engineer to come and take a look.

Tapping can also be caused by limescale build-up or sludge on the heat exchanger which will need a power flush by a Gas Safe registered engineer.

My boiler is making a banging noise

Banging noises, like many other sounds that come from a noisy boiler, are usually down to trapped air. As above, you can release trapped air from your heating system by bleeding your radiators.

In some situations, a banging noise can be due to the heat exchanger getting blocked and a large bubble popping. In this case, you may need to have a Gas Safe registered engineer come and do a power flush to get rid of debris.

My boiler is making a dripping noise

A dripping noise is most likely to be a sign of a leak in the heating system. Any leaks from your boiler or in your heating system need to be looked at by a Gas Safe engineer straight away.

Even a small leak will only get worse if left unrepaired which could cause extensive damage to your boiler, heating system and other areas of your home.

A leaking boiler (without the pressure being too high) could be a sign that your boiler is close to needing to be replaced. Rather than just replacing the faulty component, you may want to consider replacing the boiler before it completely breaks down.

Are you having to choose between a warm home and a quiet home?

If your boiler or heating system is making more noise than you would like, then it’s probably time to call a Gas Safe registered engineer to come and take a look. If you’re avoiding putting your heating on because of the noise it makes, give us a call. You shouldn’t have to choose between a warm home and a noisy one!

Here at Aura Heating, all of our engineers are Gas Safe registered and locally based, ready to solve your boiler and heating issues. If your boiler is making a strange noise, then get in touch with us today.