Geberit 290 Universal Flush

[Arpee]

First post I'm afraid - can I ask all of you for some help? We have just had a new loo installed with the above geberit flush and inlet valve. The flush initially works fine but after a while water still seeps into the cistern and eventually starts to run through the overflow. There's no leak out of the cistern - if I turn the water off via the isolation valve then overflow stops. I have also considered the fact that the water pressure may be too high but turning the flow down doesn't make any difference either. I have spoken to Geberit who thought there might be dirt in the diaphragm inside the inlet valve which was allowing water to seep in, but it was brand new and, having taken it apart I am sure there was nothing there. Anyway, out of desperation I have bought a new inlet vale and fitted this with high hopes only to find - same problem. Could it be that it's just a rubbish system? Any suggestions to diagnose the problem would be very welcome - thanks in advance.

 

[Chalked]

Good quality stuff there.
It will be dirt, or theflush valve is not seated correctly.
Why are you doing it instead of the installer?

 

[Arpee]

I'm fairly sure it isn't dirt - I changed the valve so it would be unlikely for two brand new valves to have a spec of dirt inside. I'm trying to fix it myself to try and sort it before Christmas.

 

[jtsplumbing]

Have you got high water pressure ? turning service valve down wont make any difference, cant remember if these valves come with a restrictor that fits inside the valve

 

[Arpee]

There is a pump fitted that would increase the water pressure - I don't know what the pressure actually is. I did think that high water pressure might explain this - I'll investigate further.