my vaillant boiler is saying a code com on it ?
how do I rectify the fault as detailed below?
my boiler will no work?
Vaillant VCW-Sine18 T3WFH Lights but then goes off after 5 Min?
Vaillant igniting issue ( domestic ) not CH?
Hot water supply?
No hot water, intermittent when air temp drops?
Hot water comes and goes!?
Valiant thermostat , BMU-Err ?