What does f.25 mean?
how do I rectify the fault as detailed below?
my vaillant boiler is saying a code com on it ?
vaillant ecoTEC plus boiler fault code - how to fix?
Water dripping from opening at top of pump?
Why is heating on at night?
Vaillant condensing boiler ecoTEC plus?
How many factors causes f22 fault?
Vaillant 828E - no hot water?