BoilerFaultCodes F.349 High
Boiler Fault Code F.349
Also written as F349 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code F.349 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 is struggling to measure the amount of air it needs to burn gas safely, which has caused the system to stop working for safety reasons. (As reported on Viessmann Vitodens 222-F B2TF)
Pick your boiler brand for the F.349 fix
Source
Information for the F.349 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