Probably a faulty heater tank. If you would like to call us on 0845 126 4141 we can establish which shower you have and tell you how much the part will be.
National Shower Spares
October 2008
Hugh,
the RCD is telling you that the shower has a serious electrical fault. Do not investigate without isolating the electrics to the shower. Call a plumber perhaps.
Peccavi
October 2008
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