BoilerFaultCodes F 0 9 Medium
Boiler Fault Code F 0 9
Also written as F09 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code F 0 9 appears across 1 boiler brand and 1 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 the water returning from your radiators is too hot, which suggests a possible circulation issue within your heating system. (As reported on Ferroli Arena 30 C)
Pick your boiler brand for the F 0 9 fix
Source
Information for the F 0 9 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