Sounds like you require a new solenoid assembly. Give Mira Customer Service a ring on 0844 571 5000 and they may be able to supply with a spare part. The showers very old though so you may think about replacing it with a new Mira Advance.
Bob The Builder
January 2011
yes no problems with water
rob
January 2011
any water at your taps?
ga
January 2011
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