filler valve faulty. switch water off to boiler disconect tap from pipes take care to keep o rings. test to see if water comming through to tap. then leave pipe off at opposite end of tap check opening tap slowly to see if tap working . most likely tap not opening . so renew tap. centre of taps break and cannot operate centre pin as you will find if you test by screwing in and out you can see.also check fillter first ,thats just before the tap
brian david
December 2007
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