Since fitting a new ballcock in our cistern, our water pipes have been making an increasingly loud noise when the toilet is flushed. It is now so loud that it is disturbing our neighbours.

We had been advised to lower the water pressure, which we did but this has not helped. The only thing which seems to help is to turn on the tap in the bathroom basin while cistern is re filling. pipes stop making noise after cistern has filled. Please help - it's driving us ( and the neighbours ) mad

C Power, May 2009

Change the valve in the cistern

caz, December 2013

i had the same problem, and by turning on the tap in the bathroom sink whilst the toilet is filling solved the problem. having read other fixes on the net, it seems as though it is too much pressure filling the cistern causing the ballcock to bounce about shutting the filler valve on and off. this in turn causes greater pressure back down the pipes making them vibrate loudly. So all i did was to slightly close the shut off valve inline just before the cister. by tweaking how much i closed this valve completely cured the problem. this will probably only be a temporary fix i suspect the whole ballcock and inlet valve will need replacing at some point soon, but hey no more noise :)

dave kendrick, March 2011

Hi C Power
I have the same issue - did you get a resolution?

twickmag, February 2011

We have the same problem in the main bathroom - gradually got worse over time. Now it's started on another toilet and when we run the hot tap in the kitchen! If you've solved your problem please let me know!!

LEK, September 2009

It is because the ball valve isnt opening properly so its squirting out as apose to flowing out u most likely need to replace the ball valve. try using a torvec valve. these stop water hammer n can deal with high pressure water feeds.

Emeka, June 2009

Unless someone is pulling my 'plonker'.
I have been told but am not sure of this but each ball valve is supplied with two washer plungers, one red and one blue. One is for mains fed the other for tank fed.

Now don't quote me on this but you may have the wrong plunger in the valve [what the float arm pushes against to close off the water, it pushes agains the washer]. If yours did come with another plunger then change it over. Turn off the water undo the float arm undo the large knurlled nut on the valve remove the plunger and fit the other one see what happens.

Charlie, May 2009

Had the same problem. Fixed it by changing the fixed pipe, from the cistern to the water supply tap, with a flexible braided pipe.
No problem since

Ian, May 2009

Hi

Thanks for your response. The noise is only made when cistern is actually filling. It stops once it has filled. We lowered the water pressure, as recommended, but this has made no difference except that it now fills extremely slowly and noisily. The noise is not a banging noise - more a prolonged loud droning noise - kind of like a fog horn.

C Power, May 2009

Hi

Thanks for your response. The noise is only made when cistern is actually filling. It stops once it has filled. We lowered the water pressure, as recommended, but this has made no difference except that it now fills extremely slowly and noisily. The noise is not a banging noise - more a prolonged loud droning noise - kind of like a fog horn.

C Power, May 2009

Hi

Thanks for your response. The noise is only made when cistern is actually filling. It stops once it has filled. We lowered the water pressure, as recommended, but this has made no difference except that it now fills extremely slowly and noisily. The noise is not a banging noise - more a prolonged loud droning noise - kind of like a fog horn.

C Power, May 2009

I presume the pipes are actually banging when the loo stops filling? This is called water hammer and you can only really fix it by tracing the water pipe back, and fixing plastic pipe clips where the pipe is unsupported.

John, May 2009