Water Hammer?

[eglons]

I used the shower this morning and noticed a hell of a din coming from the airing cupboard. When I looked the pipes coming from the loft were banging... I assume this is water hammer?. I turned on the cold tap in the bathroom for a few seconds and it stopped it. Nothing has changed in the plumbing for a long time so I'm confused what may have caused it.. any ideas?

 

[echoes]

Usually a ball-valve in the cold water tank not shutting the mains feed off properly (very worn mechanism, muck, worn/spit washer) and pipes not supported sufficiently.

 

[Armo74]

Check your ball valve in your CWSC to see if it is dripping. Sometimes when hot water is drawn off and the CWSC is being replenished by the float valve it can cause ripples on the water surface making the valve open and close causing the pipes to vibrate and turning the cold water tap on slowly takes some of the pressure away and stops the vibrations.

 

[picasso]

Water hammer can be caused by a worn ballcock, check the cold water tank in the loft and the toilet cistern when they are nearly shutting off.