BoilerFaultCodes 354 High
Boiler Fault Code 354
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code 354 appears across 2 boiler brands and 4 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 technical issue with the internal gas control valve that regulates the fuel supply, causing the system to lock out for safety. (As reported on Viessmann Vitodens 100-W B1GA)
Pick your boiler brand for the 354 fix
Source
Information for the 354 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 31 August 2026