Boiler Fault Code Air flow rate safety device

Also written as AIRFLOWRATESAFETYDEVICE — same fault.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026

Fault code Air flow rate safety device appears across 1 boiler brand and 3 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 air cannot flow correctly through the exhaust flue, so it has safely shut itself down to prevent any harmful gases from building up. (As reported on Saunier Duval Sylva)