We may have found other answers which could help you.
Click here for Vaillant Off 5Hot water comes and goes!?
Vaillant vcw gb242 eh central heating problem?
Vaillant eco plus 531 boiler?
Vaillant condensing boiler ecoTEC plus?
Vaillant ecotec 831 plus?
vaillant ecoTEC plus boiler fault code - how to fix?