BoilerFaultCodes Blue light High
Boiler Fault Code Blue light
Also written as BLUELIGHT — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code Blue light appears across 1 boiler brand 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 working for safety reasons and is waiting for you to manually restart it to try and clear the fault. (As reported on Worcester Bosch Greenstar 12i System)
Pick your boiler brand for the Blue light fix
Source
Information for the Blue 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