While you wait for answers, we may have found some information which could help you.
Success
Message
Re Pressurise system?
Diverter Valve Replacement?
vaillant boiler trips house electrics when hot tap on?
Vaillant Turbomax 824 overheats very quickly in heating mode?
boiler starts then soon stops?
Cannot turn radiators off,?
We have no hot water?
SERVO VALVE ON VAILLANT BOILER?
Vaillant turboMAX 824E?
water dripping out of overflow pipe from boiler when CH on?
HW issues w. Vaillant boiler?
Boiler over pressure on the hot-water side?