We may have found other answers which could help you.
Click here for Vaillant Turbo Pro 28eVaillant VCW-Sine18 T3WFH Lights but then goes off after 5 Min?
Vaillant eco plus 531 boiler?
how do I rectify the fault as detailed below?
vaillant ecoTEC plus boiler fault code - how to fix?
Vaillant ecotec 831 plus?
Vaillant 828E - no hot water?