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Knocking sound in cold water supply

Posted: Wed Mar 10, 2010 12:43 am
by rynso
Hi,

Our cold water system has started knocking when taps etc are turned on and off. There is a noise like the pipe is being hit with a rubber hammer, but it is difficult to locate exactly where the noise comes from.

Any ideas of the cause and suggested solutions please?

rynso

Posted: Wed Mar 10, 2010 7:36 pm
by htg engineer
'There is a noise like the pipe is being hit with a rubber hammer'

It's called water hammer, caused by water coming to a sudden halt (closing a tap) causes the pipework to vibrate. This can be rectified by supporting pipework (clips) if any pipes are touching each other/floorboards/pipe boxing etc, clip and lag/insulate pieps

Firstly though, try closing the mains stop tap slightly.

Or if none of the above work, you could fit a water hammer arrester.


htg

Posted: Thu Mar 11, 2010 9:48 pm
by rynso
[quote="htg engineer"]'There is a noise like the pipe is being hit with a rubber hammer'

It's called water hammer, caused by water coming to a sudden halt (closing a tap) causes the pipework to vibrate. This can be rectified by supporting pipework (clips) if any pipes are touching each other/floorboards/pipe boxing etc, clip and lag/insulate pieps

Firstly though, try closing the mains stop tap slightly.

Or if none of the above work, you could fit a water hammer arrester.


htg[/quote]

Many thanks.

rynso