how do I rectify the fault as detailed below?
Vaillant ecomax 828/2 e water pressure sensor?
Vaillant F22 fault?
vaillant ecoTEC plus boiler fault code - how to fix?
No hot water, intermittent when air temp drops?
Vaillant igniting issue ( domestic ) not CH?
Boiler over pressure on the hot-water side?
how do I vent the heat exchanger?
Problem with the pressure in combi boiler?