BoilerFaultCodes 3 flashes green High
Boiler Fault Code 3 flashes green
Also written as 3FLASHESGREEN — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code 3 flashes green 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 stopped because it cannot keep the internal fire lit, meaning you currently have no heating or hot water. (As reported on Main Insul 7)
Pick your boiler brand for the 3 flashes green fix
Source
Information for the 3 flashes green 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