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Thanks I’ll try this, wasn’t sure whether the seating could be a problem with it being the quater turn ceramic cartrdige (rather than the valves with a tap washer) thanks againIt's probably a seating problem. The machined surface of the tap casting underneath the cartridge must be in very good condition so that the silicone gasket at the bottom of the cartridge forms a water tight seal. Inspect and clean / polish / descale / regrind / replace tap body (depending on severity of problem).
Reply to the thread, titled "Tap still dripping after valves have been replaced?" which is posted in Bathroom Advice on Plumbers Forums.
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