While you wait for answers, we may have found some information which could help you.
Success
Message
Vaillant condensing boiler ecoTEC plus?
Vaillant vcw gb242 eh central heating problem?
Advice?
Vaillant ecotec 831 plus?
how to fix water pressure its down at bottom of grey part?
Vaillant F22 fault?
Problem with the pressure in combi boiler?
Vailliant turbo max plus 824e?
Vaillant eco plus 531 boiler?
how do I rectify the fault as detailed below?
Vaillant 828E - no hot water?
Vaillant VCW-Sine18 T3WFH Lights but then goes off after 5 Min?