BoilerFaultCodes F.383 Emergency
Boiler Fault Code F.383
Also written as F383 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code F.383 appears across 1 boiler brand 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 that a valve responsible for controlling the fuel supply might be stuck open, which stops the system from operating safely. (As reported on Viessmann Vitodens 100-W WB1A)
Pick your boiler brand for the F.383 fix
Source
Information for the F.383 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