my vaillant boiler is saying a code com on it ?
how do I rectify the fault as detailed below?
Valiant thermostat , BMU-Err ?
How many factors causes f22 fault?
Vaillant igniting issue ( domestic ) not CH?
Vaillant eco plus 531 boiler?
Vaillant vcw gb242 eh central heating problem?
No hot water, intermittent when air temp drops?
How can I fix my Vaillant turbomax 828 ??