5 Disturbing Noises Boilers Make and What to Do about Them

Household sounds are widespread and typically not cause for concern. On the other hand, a loud boiler easily takes the top rank in the home for the most worrisome variation of noises.

A boiler may generate a variety of noises, some of which are innocuous and others that require more investigation.

How to Fix Common Boiler Noises

To begin, it is critical to pinpoint the source of the noise. Is your boiler pounding loudly, or are the strange sounds coming from a radiator or central heating pipe? If you hear a creaking sound, it may be the sound of pipes changing temperature, which is very natural.

You’ll be able to diagnose the problem once you’ve determined where the noise is coming from.

1. Banging

A surprising amount of sounds within a loud boiler and your pipes and radiators are caused by trapped air. Fortunately, this is one of the simplest issues to resolve. The boiler cannot be bled, however, bled radiators should remove any trapped air in the system.

You’ll need a key, which is readily accessible at hardware/DIY stores if you don’t already have one. Insert the key into the little nut at the top of the radiator. You’ll hear a hiss of air; after this sound stops, turn the key back on. A blockage in the heat exchanger is a remote possibility, but the air in the system is far more likely.

If bleeding the radiators does not resolve the issue, a buildup of dirt on the heat exchanger is most likely to blame. You’ll need to have a plumber perform a power flush at this point.

2. Whistling

If your boiler is whistling, it could be that kettling has occurred. This happens when there’s a buildup of limescale inside the boiler, which then causes the water to boil and creates a loud whistling noise. If this is the case, you need to get a power flush to clean your system.

3. Humming

If your boiler is just making a consistent humming noise, it’s most likely because the water pressure is too high. This can be easily fixed by bleeding the radiators until the water level falls to where it should be – around 1 bar. You can check this using a pressure gauge, which is normally located on the front of the boiler.

If your water pressure keeps falling and needs regular topping up, there may be a leak in the system somewhere. A plumber can find and fix this by looking at the pressure gauge on the front of your boiler.

4. Vibrating

If your boiler is vibrating, it might just be that it’s not properly secured to the wall. This can usually be remedied by tightening any screws or brackets holding it in place. If that doesn’t work, the problem is likely with the motorized valve controlling the flow of water into the boiler. You’ll need a plumber to take a look at this and replace the valve if necessary.

5. Clicking

A clicking noise coming from your boiler is usually just the sound of the ignition trying to light the pilot light. If your boiler is gas-powered, then it will have a pilot light that ignites the main burner. If this light goes out, then the clicking noise will start as the boiler tries to relight it.

If you can see the pilot light and it’s lit, then the clicking noise is likely caused by a buildup of dirt or debris in the burner. This is a common problem and one that you’ll need to get a plumber to sort it out for you.


So, there you have it – the five most common boiler noises and what they mean. If you’re still unsure or are worried about any unusual sounds coming from your boiler, the best thing to do is get a professional in to take a look.

If your boiler keeps making disturbing noise, don’t hesitate to call in an emergency plumber. Here at Bromac Mechanical, you’ll be assisted by a licensed residential or commercial plumber with experience in aiding Abbotsford homes and businesses through the smoothest plumbing repair services. Call 604-360-2710 for a quote or a request for emergency services.

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