Burner reset light red flash (0.5s) High

Boiler Fault Code Burner reset light red flash (0.5s)

Also written as BURNERRESETLIGHTREDFLASH05S — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code Burner reset light red flash (0.5s) appears across 2 boiler brands and 2 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has stopped because it thinks it sees a flame when there shouldn't be one, which is usually caused by a dirty sensor or an incorrect air-to-fuel mix. (As reported on Grant Vortex Blue)

Pick your boiler brand for the Burner reset light red flash (0.5s) fix

Grant Burner reset light red flash (0.5s) 1 model Worcester Bosch Burner reset light red flash (0.5s) 1 model

Source

Information for the Burner reset light red flash (0.5s) 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