Electric shower PRD Quartz Electric/Lumi/ Sassi Replacement Pressure Relief Device (Outlet pipe). The PRD is a safety feature which will activate only when a blockage (even temporary) occurs whilst the shower is in use, e.g. a shower hose kink or restriction of the flow from the shower head. Once activated, water will flow from the PRD behind the front cover, down the wall surface when the shower is running. Please note that once the PRD has been activated, the blockage must be cleared and the PRD must be replaced. This part number is for use with Lumi Electric, Quartz Electric and Sassi Electric shower models.
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