Boiler expert warns about sounds you should never ignore and what they mean

A plumbing expert has warned of noises you should never ignore if you notice they are coming from your boiler. Andy Kerr, Founder and CEO at BOXsays that if your boiler is making a noise that differs from how it usually sounds, it’s best to act quickly to prevent further damage.

Although a noisy boiler is not always a cause for concern, there are certain noises to be aware of. He warns, “Each comes with its own reasons and remedies” — including hissing, banging, gurgling and banging.

“Remember, never try to fix anything yourself if you’re not sure. You should always call a professional if you are in doubt about noises coming from your boiler.

“Troubles that cause your boiler to make noise can usually be fixed quickly. But if your boiler is old and ready to be replaced, there’s a chance the problem is something more serious, and in these cases it’s important to be aware that it could be time for a new boiler.”

Hissing/hissing/high-pitched sound:

One cause of a noisy boiler could be boiling, which happens when the flow of water through the boiler slows down, causing the water to overheat and reach its boiling point – this is when a boiling noise is heard .

More often than not, this can be the result of circulatory problems, meaning water is not being pumped or moving around the system efficiently. This could indicate a faulty pump and/or central heating system problems.

The boiler can be a serious problem that should be looked at by a Gas Safe engineer, but common causes include:

• Limescale build-up

• A leaking boiler or system with an incorrect amount of water

• A faulty thermostat, causing the boiler to overheat

• The pump is defective

Bump:

If you hear a clicking or knocking noise, your boiler may be struggling to light. A potential cause for this is a faulty ignition.

In this scenario, this is not something you should try and fix yourself, you should call a Gas Safe engineer as it could be related to the gas supply to your property.

Gurgling/dripping/bubbling:

Although there are other causes, for the most part a gurgling noise is caused by air trapped in the radiator. Sometimes the gurgling sound coming from your water heater is just the hot water moving around, so there’s nothing to worry about.

However, if the sound is persistent and happening more frequently, it’s best to take a quick look at the following.

• Vent the radiator: the gurgling sound could be coming from an appliance associated with the boiler, such as a radiator. After draining the radiator, check the boiler pressure and top up if necessary. A drop in boiler pressure can lead to other problems. If the noises continue, the problem lies elsewhere.

• Check the water pressure: low water pressure could cause the gurgling noise. Look at the pressure gauge in your boiler cabinet, if the dial is in the red section, the pressure is too low and your boiler needs to be re-pressurized.

If the problem persists, there could be something else wrong with the boiler. Speak to a Gas Safe registered engineer who will be able to help you resolve the situation.

Hitting sounds:

A loud noise can come from limescale build-up inside the heat exchanger, a faulty boiler thermostat or something as simple as an incorrectly set thermostat.

You may want to call in a heating engineer who can check the return and return pipe temperatures to check for overheating and also check that the boiler thermostat is set to the correct temperature. If none of the above is causing the problem, they may need to access the pipes under the floor to check that it is properly attached and supported.

A Gas Safe registered engineer can also determine if the problem is with your system’s circulating heat exchanger, in which case you may need a boiler. flushing the heating system to correct the problem if it is the result of a build-up of magnetite, debris or dirt.

Buzzing sounds:

A noise from your boiler can be worrying and the best course of action is to get help from a professional. Numerous problems could cause a buzzing sound, from faulty electrical components to a blocked pump.

If you hear your boiler making a humming sound or it seems to be humming from you, you should have it checked out. Essentially, the whining noise is your boiler calling for help. It means it needs to be fixed right away and you need to call a professional to do it.

Whistling/sounding like a washing machine:

Noise noises are especially prevalent in combination boilers. These noises coming from your boiler are usually caused by a stuck circulation pump or trapped air in your system.

For this sound, you should contact an engineer who can check for blockages or trapped air and diagnose the problem.

Alarm sounds:

If there is an alarm sound from your boiler, it is usually a signal that something is wrong. Common causes of this are low water pressure, a faulty thermostat and blockages.

Troubleshoot your boiler by checking the water pressure and thermostat, if these are working and the sounds persist, contact a Gas Safe registered engineer.