Compact 25he

[Nwalky]

Was at this Vokera yesterday and found the heating and hot water not working, cleaned the venturis and got it going however; still had an issue with the hot water overheating (heating controls seem to be fine), replaced the hot water thermistor and still over heating, looking through the diagnostics its looking like it might be the board next but thought i would see if anyone on here could have any other suggestions before i commit to this diagnosis. Obviously its an old boiler so they might not want to keep it going and i dont think its the plate heat exchanger because my experience with those being blocked is that the water would be luke warm rather than boiling, high limit stat is cutting the boiler off as it should and the boiler is not going into lockout or giving any error lights. Any suggestions would be welcome. Thanks

 

[ShaunCorbs]

What’s the mains flow rate eg out the hot tap ?

 

[Nwalky]

What’s the mains flow rate eg out the hot tap ?

I never had my flowcup when i was there to check it unfortunately