A up lads, have Protherm 80 e with no hw. When i open hot tap boiler fires but sends some heat down heating flow and some heat round hw heat exchange, the flow from main heat exchange gets way to hot and then boiler goes off on overheat, have tried diaphram on diverter to no avail. I am thinking diverter is not fully moving over to hw and also hw heat exchange is blocked, any idea's would be appreciated.