What does f.25 mean?
my vaillant boiler is saying a code com on it ?
Water dripping from opening at top of pump?
Vaillant ecomax 828/2 e water pressure sensor?
Vaillant Ecotech Plus 831 F22 fault?
Boiler over pressure on the hot-water side?
Vaillant eco plus 531 boiler?
how do I rectify the fault as detailed below?
how to fix water pressure its down at bottom of grey part?