Diverter valve could be stuck in hot water demand, check pin on diverter valve, What boiler do you have?
justin
January 2008
a lot off new boilers have a pump overrun to cool the boiler when switched off this usually switches off after 10/15 mins---poss overrun is faulty or if you have a frost stat fitted if boiler outside this may be up too high
wp
December 2007
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