BoilerFaultCodes F.077 High
Boiler Fault Code F.077
Also written as F077 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code F.077 appears across 1 boiler brand and 3 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler has detected an issue with the drainage system or flue safety mechanism, so it has safely stopped working to prevent potential water damage or combustion faults. (As reported on Vaillant ecoTEC plus)
Pick your boiler brand for the F.077 fix
Source
Information for the F.077 fault code is sourced from the official service / installation manual for each model that displays it. Read more about how we source fault codes →
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026