Got Noisy Central Heating Pipes? Here’s Why. And, The Fix.

Are your noisy central heating pipes driving you insane? Rightly so. And even if they’re not, there’s a good chance you want to know what’s behind your noisy central heating.

In this 5-minute guide, we’ll cover everything you need to diagnose the problem behind your noisy heating pipes.

We’ve split the guide into:

• The problem behind noisy pipes.
• The noises you’ll hear.
• The fix.

Want someone to fix your noisy pipes? Get a quick quote here.

Typical Sounds Coming From Noisy Heating Pipes

Each property is different, but depending on the pipework’s age and condition, your noisy central heating may produce the following sounds: 

• Banging
• Rattling
• Clunking
• Vibrating
• Tapping
• Clicking
• Knocking

5 Reasons You Have Noisy Heating Pipes 

#1 – Natural Start-Up Process

You may hear: banging, knocking

First things first: hearing your pipes banging when the boiler comes on is completely natural.

Pipes, radiators, and every other part of the heating system will expand as it heats up. And, a normal heating system will take anywhere from 10-30 minutes to heat up fully.

So, if you hear noises such as tapping, banging, and knocking that comes from the floor boards and walls for this period only, it’s likely due to the natural start-up process of the heating system.

Also, expect to hear similar noises in the heating pipes when you turn your heating off — the pipes will be contracting.

The Fix

Does your noisy central heating produce more of these sounds in a specific area of the house? A heating engineer will find this area and re-route the pipework, so it’s got adequate space to expand without touching the floorboards.

#2 – Limescale And Sludge Build-Up

You may hear: clicking, tapping, rattling, boiler kettling

Limescale build-up often happens in hard water areas, and could easily be the cause behind the tapping noise in central heating pipes.

Another possible culprit is central heating sludge, which builds up in most systems. Essentially, it’s rust on the inside of pipes breaking off and circulating around the system.

In either of the situations, you can expect to hear noises that sound like grit trickling through your pipes, so tapping, rattling, and clicking noises are most common here.

Other symptoms of limescale or sludge build-up include radiators that are cold at the bottom, and your boiler operating at reduced efficiency and making kettling noises.

The Fix

To remove this build-up and fix your noisy central heating, get an engineer to:

1. Dose your heating system with inhibitor, as this will break down limescale and heating sludge.
2. Flush your system to remove as much sludge and limescale as possible.
3. Fit a scale reducer, for those in hard water areas; this will catch limescale before it builds up.
4. Fit a magnetic boiler filter (all areas); this will catch central heating sludge.
5. Remove debris from scale reducer and magnetic boiler filter with each annual boiler service.

#3 – Unsecure Pipes

You may hear: banging, tapping, clunking, knocking, vibrating, humming

Noisy heating pipes could be making all these sounds if they’re not properly secured.

When pipes are not held in place, they will move as the hot water travels through them. And, given their proximity to the floorboards, they will come in contact with the latter and produce a wide array of different noises.

The cause is relatively straightforward — either the pipes weren’t ever secured properly, or they’ve broken free from their pipe clips.

The Fix

If your noisy central heating pipes have simply broken free from their clips, all you have to do is re-secure them.

If the pipework is already secured with pipe clips, you may need to reroute it to stop the knocking and humming noises you’re hearing.

To do this, the system needs to be drained, sections of pipework cut out, new pipe work fitted, and the system refilled.

We’d suggest getting help from a heating engineer.

#4 – Airlocks In Pipework

You may hear: banging, knocking, clunking

If you hear clunking, a harsh banging sound, or knocking in the pipes, the cause of your noisy central heating is probably an airlock in the pipework, radiators, or pump. Other signs of this problem include radiators that don’t heat properly and taps that don’t produce water.

Luckily, airlocks are incredibly easy to remove from heating pipes and radiators.

The Fix

Bleed all the radiators with the heating on; you’ll need a radiator bleed key to do this.

Slowly open the bleed valve until you hear hissing. Hold it at that position until the hissing stops, and the valve starts to drip with water. Shut the valve.

Rinse and repeat for all radiators and towel rails.

And, a word to the wise — if you’ve not bled a radiator before, be careful.

#5 – Water Hammering (When Using Taps)

You may hear: loud knocking

Another reason for knocking sounds and noisy central heating pipes is something called water hammering.

What is water hammering?

A sudden surge in the water circulating through the pipework, which often creates noises such as knocking in pipes.

What causes water hammering noises?

Anything that requires a sudden surge of water (and not necessarily hot water):

• Taps
• Showers
• Toilets

The Fix

Fit a water hammer arrestor. This device acts as an “overflow” for pressure and energy.

When the surge of water is likely to create a water hammering noise, the water hammer arrestor will absorb the excess energy – no more noisy pipes!

What’s Next?

Thanks for reading our guide to noisy central heating pipes.

Want someone to fix your noisy pipes? Get a quick quote here.

And, click here if you think noises are coming from your boiler.

We’re happy to help, so if you have any questions, drop a comment below and we’ll get back to you as soon as possible.

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