my shower is doing exactly the same. first thing i done was check filter at inlet - this was clear. Took shower to bits no blockages. Surmising its some sort of electrical fault - trying to find it is the problem - answer......... new shower.
askewcools1
August 2008
gauze filter on mains water pipe connecting to shower blocked with scale
HI-SPEC PLUMBING
August 2006
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