BoilerFaultCodes F.402 High
Boiler Fault Code F.402
Also written as F402 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code F.402 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's main internal computer has developed a serious electronic fault and can no longer safely control the burner, meaning your heating and hot water will not work. (As reported on Viessmann Vitodens 222-F B2TF)
Pick your boiler brand for the F.402 fix
Source
Information for the F.402 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