Boiler Fault Code Red LED: Rapid Flashing

Also written as REDLEDRAPIDFLASHING — same fault.

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

Fault code Red LED: Rapid Flashing 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 has failed to start up because it is struggling to detect a flame, likely due to air being trapped in the gas supply or a minor mechanical hiccup. (As reported on Potterton Prima 30B)