Unusual flush valve in concealed cistern

[Mike Hall]

Hi All,

I have an apparently very common issue (water won't stop flowing into toilet) with a concealed cistern. I've looked at a few videos and googled quite a lot, but I'm drawing a blank so I was hoping someone might have an idea...

I've attached a couple of pictures. You push the plate, and it lifts up that central tube to allow the toilet to flush. The tube also seems to double as an overflow valve but I can't for the life of me figure out what the extra plastic on the right of the tube is for.

From draining the cistern of water and then turning the water back on, I've found that the running water starts when there's very little in the cistern at all so it doesn't seem to be an overfilling problem.

Does anyone have any idea what the issue might be, or how to fix it? If I need to replace the flush valve, how do I get it out, and does anyone have any idea what brand this is so I can find one to order?

Thanks for your help.

Mike

 

[Mike Hall]

Just to add, the closest I've found is the Gerberit AP109. Are these things generally universal and interchangeable?

 

[Gasmk1]

silicon washer bubbled probably

 

[king of pipes]

The flush seal on these blister and leak they can be changed easily though as a quick fix take it off and turn it over .kop