probably a common issue - have a dual flush toilet with a bottom fed boat float valve (like a Roca 1/2" on lunns website). The cistern keeps filing until the water pours down the central cycliner of the Flush valve (looks like a Roca D2D post 2006 on Lunns website), into the toilet bowl, so I am assuming that the float valve is not cutting off.
I have tried adjusting the float by turning the screw thread at the top, but to no avail - is there any other ways of adjusting the float valve?
In addition, there is a plastic flap that hangs down where the vertical screw rod joins the top arm - I cant see it in the picture on the Lunns website, so does it need to be clicked in anywhere?
your water pressure is either too low to operate the float valve correctly, or the valve is simply faulty and needs renewal. the plastic flap you describe is a 'silent fill' device to deaden the sound of the incoming water. not essential.
mark, WRAS plumber
October 2008
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