Tolilet keeps flushing

[David Goff]

Hi, On flushing my WC sometimes decides to keep going, it isn't that the water trickles into the pan after a flush , rather it restarts the whole flushing procedure again. Which bit do yo reckon I need to replace?

 

[Bamber gaspipe]

Don`t know what model you have. integral overflow? ballcock arrangement? Continental double flush?...help me out over here..

 

[meldrew's_mate]

You probably have a traditional syphon (lever flush) with internal overflow (no external warning pipe through your walls).
Could be the ballcock needs replacing, repairing, or adjusting. Check the water level is 2" or more below the top of the syphon assembly, or 1" below the invert level of it.

 

[David Goff]

Hi People, set up is a tradition lever type but does have an external overflow pipe. The valve to let to refill the cysten is working fine but doesn't get a chance to stop the water as the thing starts flushing again before the cysten refills. Have I got a ghost?

 

[meldrew's_mate]

Aha!!!
Have you had the syphon replaced, pehaps with one which is too short? In this case the water reaches the invert level before reaching the overflow level.
Manually lift the ballcock when the water level reaches 2" from the top of the syphon - then flush. If the flush is OK set the ballcock so it controls the water at that level, and make a note to contact the plonker who fitted the wrong syphon.

 

[Bamber gaspipe]

Call me a mad fool but.....you have a traditional toilet, lever type, you are saying that the toilet, of it`s own accord.. is flushing itself...YES, YOU HAVE A GHOST..

 

[meldrew's_mate]

Call me a mad fool...

OK.

 

[Nige F]

the syphon is weak.....and the water is coming in too fast.......end of Let the Certified CORGI`s reply and tell you which part to renew.......Syphon or Ballvalve

 

[David Goff]

Hi again, Thanks for the ideas. I think I've not described the symptoms well enough.
The syphon has not been replaced but I did replace the flaot valve to silence it and stop it dripping. This aspect has now worked fine.
The set up is the only kind I've ever seen in oldish toilet, float valve, pipe for overflow running through the wall.
Problem doesn't happen every flush but when it does it goes something like this;
Flush seems fine, float drops fine, water comes into cysten fine but doesn't get a chance to raise the float again as the toliet continues to flush out. The mechanical nature of this does seem to mitigate againstn the idea of a ghost so I withdraw that suggestion. Any other ideas?
Cheers

 

[croydoncorgi]

If you've got a service valve on the feed to the cistern, close it a bit to reduce the flow.
The objective is to stop the cistern partly filling before the syphon has drawn in enough air to stop syphoning.

 

[Nige F]

There ya go

 

[David Goff]

Hi yet again, in other words the little hole on the side of the plastic syphon has to remain uncovered by water for a few seconds to let air in and put pressure on it? Am I right? So slowing the water intake should do this. Thanks, it has worked for the first few flushes, time will tell.

 

[croydoncorgi]

No, no, no! You clearly missed the bit at (junior) school where they play with bits of tube and water and find that a syphon with air in it ain't a syphon! To work, there has to be continuous water all the way over the humpy bit just below the lid!

 

[David Goff]

Ok, I missed a lot of junior school but we didn't do a lot of plumbing any way. I don't think I understand the principal bt turning the water pressure down appears to have stopped the problem so I'm happy. Thanks for the help.

 

[Nige F]

Recon you caught a sermon when you only needed the verse which I provided the hole in the side is a cheapo way to reduce the volume of the flush.....plug it and you get 9 litres.......leave it open and you get 6.....call in a corgi and you get ££££ I`m back to the verandee fer sum Banjo pluckin now