Sounds like the pressure relief device so you will need to ask for one of these. If you are in a hard water area this may have caused it and it could go again. Another possible cause is a shower-hose or showerhead in poor condition, replace these if necessary.
Good luck
Paul M
May 2009
if you still need help telephone 0845 126 4141 National shower spares, i think you shower is a TRITON not a Mira, cheers Gary
gary
May 2009
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