Help please toilet cistern noise at night

[Jane23458]

for the last few months we all been woken in the house by a mysterious noise at odd times through the night, and think it happens during the day too. We've traced it to the upstairs toliet. Its like the noise when the washing machines is filling, goes on for a few seconds, then ends with a bang, as though something shuts off. Reading these forums thought it might be the toilet system emptying itself at night? Any advice welcomes on how to stop this thanks

 

[justlead1]

Hi Jane, Is the water supply system shared with others? Is the WC cistern a newish type? My first test (if i live in the house)would be to tie the float valve in the cistern in the closed position with a piece of string, prior to going to bed. This will stop any filling with water and confirm or eliminate the wc arrangements as the problem.

 

[Phil]

My guess is its a push button toilet and the flush valve is trickleing into the pan, so the float valve is constantly topping up the cistern.

Look into the pan and see it you can see the water rippeling as it runs down the back of the pan.

 

[Jane23458]

thanks both very much, we'll try your suggestions, apols for delay in replying