Boiler fire,s up fine for hot water and heating . But when heating is left on the presure rise to 3 bar, when i turn it off it goes back to normal . Checked expansion unit presure and water came out of valve , is this the promblem .
more than likely expansion vessel is dead if you got water from valve. vessel half is air section and half water section seperated by rubber diaphragm.
fitting remote vessel to central heating return pipe cheaper alternative than replacing original providing you have somewhere to locate as they aint the neatest of fella's
iain
July 2008
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