BoilerFaultCodes 446 High
Boiler Fault Code 446
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code 446 appears across 1 boiler brand and 1 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 a conflicting reading between its internal temperature sensors and has shut down as a safety precaution to prevent overheating. (As reported on Viessmann Vitodens 100-W B1GA)
Pick your boiler brand for the 446 fix
Source
Information for the 446 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