Flush valve leaking into toilet

[Fredstudio]

Do you change the flush valve washer in this instance, or unit?

 

[Wayners]

So it keeps filling up? This causes water to overflow over the syphon and run down the toilet pan.
If you adjust float will it stop?

If it keeps running change the washer if you can locate the correct replacement

 

[Fredstudio]

It keeps running in to pan, water level below overflow

 

[ChrisJP]

You need to find out and then explain whether it's the flush valve at the base of the cistern that is leaking (assuming you don't have an older siphon flush), or whether the fill valve is not shutting off properly so the cistern is overflowing. Modern cisterns overflow into the toilet pan, so either of these faults will result in water continually running into the pan.

 

[Fredstudio]

Thanks it's this valve I think I have found the correct washer anyone swapped the washer on these flush valves. Is an ideal standard toilert so want to avoid stripping the cistern down.

 

[Rodders53]

Turn off water to cistern.

Clearly it is a Geberit flush valve --- it is written on the top. It will be a bayonet fit (twist off carefully anticlockwise around 30 degrees typically) then lift it up and out; the rubber diaphragm washer can then be accessed for replacement.

< Geberit Ideal Twico > looks to be the most likely one... available from all good toilet spares suppliers.

Search for the installer manual to read if you think it'll help.

 

[dilalio]

It keeps running in to pan, water level below overflow

Then it will be the dump valve.
What type is it?
Can you remove it and clean the washer?
Reverse it?

 

[jj4091]

https://www.diy.com/departments/diy-upgrade-geberit-twico-i-dual-flush-valve-includes-buttons/5055639195370_BQ.prd