Question

I have central heating pipes that rattle very badly if i turn off the rads down stairs it stops.
Any suggestions?

Answer

If your central heating pipes make loud rattling noise, there are different possible causes. It could be air in the system which needs to be let out by bleeding the radiators; could be radiator valve rattling;  could also be your pump valve; could be loose duct work or pipes expansion noise. But before I begin to address this, it's important that I know the type of system you have and at what point the problem started. Is your central heating gas or electric? Is it an old system? Was there a recent repair done on the unit before it started rattling? We always urge users to give such details in their questions to enable us give accurate answers since we are not present to look at the system.

Common causes of central heating pipes making a rattling noise and solutions
Air in radiator
How to fix: Bleeding the radiators will fix it if the problem is air in your system. Calling a professional is highly recommended. But if you can follow carefully steps on how to bleed a radiator below, you can do it yourself.

How to bleed a radiator

Locate a small valve (usually square shaped) at the top of your radiator. Locate your radiator's groove and using a screw driver, carefully and gently slacken the square peg until air escapes and water starts to come out. If your radiator has no groove, then you need to get a radiator bleed key from your local supply shop. Using the radiator bleed key, gently and carefully slacken the square peg until you hear a slight hissing sound which indicates that air is escaping from your system. Continue releasing the air until water comes out. When the water runs continuously with no trace of bubbles, then tighten the peg back in. Attention: Never take the peg out of the radiator, only loosen it slightly, I repeat loosen it slightly. Do not take the peg out of the radiator for any reason.

Be aware that water in the pipes and radiator will make a gurgling or rattling noise. And if the radiator has not been bleed in a long time, get ready for a lot of very dirty water. Place an old cloth under the valve and use a bucket to collect water. Removing all traces of air from your system will fix the problem in this case.

More causes of a rattling central heating pipe

• Radiator valve rattling
• Two pipes touching
• Pipes expanded by hot water running through them over time
• Minerals and certain bacteria react with alloy heating elements to cause rattling noise
• A pump valve rattling

Advice:
Call a professional to diagnose and fix the problem that causes your central heating pipes to rattle.

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