BoilerFaultCodes Red lockout light High
Boiler Fault Code Red lockout light
Also written as REDLOCKOUTLIGHT — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code Red lockout light appears across 1 boiler brand and 7 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 an issue and stopped working as a safety precaution, likely because the fuel supply is interrupted or the internal pipe for water drainage is blocked. (As reported on Ferroli F 30 B)
Pick your boiler brand for the Red lockout light fix
Source
Information for the Red lockout light 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 27 April 2026