Hi,I am having trouble with toilet back filling,it’s a Twyfords toilet,I have replaced the flush seal and it’s still passing through,I then bought a new flush value still no good! It’s a new build just out of warranty two of the toilets loose water,we had one of the toilets flush seals replaced twice while under,many thanks for any ideas,Richard
When you say backfilling do you mean it's leaking from around the donut seal or running into the pan?
Could be the water level in the cistern is to high and therefore over spilling into the pan, may just require a simple adjustment or a new washer in the filling valve. Worth a look on YouTube as may be of help to you.
I’ve tried the water level lower n it still comes through,it only stops when it’s below the flush seal
Either the flush valve seal washer isn’t sealing for some reason, - or the flush valve itself has not been sealed onto the cistern base and is constantly leaking through the base and onto the pan. Some cisterns have misshapen bases
If all else fails, the flush valves and push button could be replaced to a different and reliable common brand
It is great to have a standard valve you can simply reach in and remove from its base (bayonet or clip on types) and replace the washer or entire valve in the future, leaving the base part and cistern untouched. But they are all poor in my opinion. A lot of plumbers prefer fluidmaster flush valves. I quite like Wirquin flush valves. The water in your area might be harsh on the washers.