you need to release pressure from the unit. did anyone alter the shower head settings whilst the water was running? sometimes a short rise in pressure will pop the prd device. its just a small plastic ring with a fine sheet of polythene inside. usually charge £8 for two!!!! yes i know. just switch all off, water + lecky. remove and reinstall the new prd and job should be a goodan.
woody
January 2013
descale shower head replace shower hose replace PRD (Pressure relief device) job done easier than replacement
Dave
May 2012
unit was under pressure and safey valve given way, it will be cheaper to replace than to repair
k
May 2012
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