Valiant thermostat , BMU-Err ?
No hot water, intermittent when air temp drops?
Vaillant Ecotech Plus 831 F22 fault?
vaillant ecoTEC plus boiler fault code - how to fix?
no heating water?
my vaillant boiler is saying a code com on it ?
Vaillant vcw gb242 eh central heating problem?
Vaillant eco plus 531 boiler?
resetting thermostatat?
Hot water comes and goes!?
Vaillant condensing boiler ecoTEC plus?
how do I rectify the fault as detailed below?