how do I rectify the fault as detailed below?
Valiant thermostat , BMU-Err ?
Vaillant ecomax 828/2 e water pressure sensor?
Vaillant Ecotech Plus 831 F22 fault?
Boiler over pressure on the hot-water side?
my boiler will no work?
Vaillant igniting issue ( domestic ) not CH?
vaillant ecoTEC plus boiler fault code - how to fix?
No hot water, intermittent when air temp drops?
Vaillant vcw gb242 eh central heating problem?
Problem with the pressure in combi boiler?
my vaillant boiler is saying a code com on it ?