I have a toilet with a Siamp Optima 40 dual flush mechanism. When I flush, the water in the cistern quickly fills to a level roughly half way up the overflow. But if you leave it for a while, it slowly keeps filling it until the water gets to the top of the overflow and starts to trickle into the bowl. How do I make an adjustment to make sure that the water level is never filled beyond the overflow? I've printed some stuff off the Siamp website but don't really understand it. Grateful for any help.

Alistair., November 2009

I have had the same problem on a valve fitted 2 months ago replaced diaphragm today re ajusted level and still water level rising so I thought I would check to see if any body else having problem before contacting siamp.I have been a plumber for over 20 years .Bring back the old fashioned ball valves .fit and forget!

s riding, June 2013

I have the same problem
The Siamp website is pretty useless - from what I can ascertain its something to do with the inlet valve not shutting off.....

Louise, July 2010