Usually a sign the plate to plate heatexchanger is sludged or scaled up and may need replacing.
But first check the inline water filter in the mains inlet pipe to the boiler, it can get blocked with scale and cause same types of problems. Also check the dhw thermister
T
May 2008
Automatic Answer
We may have found other answers which could help you.
howtomendit.com for free repair help, information and advice.
