Vaillant error codes

24 codes that Vaillant publishes for a boiler, each quoted from the maker’s own manual or support page and explained on its appliance’s page. Pick the appliance, or type the code from the display: only Vaillant codes are searched here.

Every Vaillant appliance we cover

Gas boiler: do only the checks its user manual gives you — read the pressure gauge, top up through the filling loop, press the reset button, thaw a frozen condensate pipe at ground level. Keep the casing on and leave sealed parts alone. Anything else is for a Gas Safe registered engineer. If you smell gas, call the National Gas Emergency Service on 0800 111 999. Two Vaillant models can use different codes: your model’s manual is the authority.