neon 1 not lit High

Boiler Fault Code neon 1 not lit

Also written as NEON1NOTLIT — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code neon 1 not lit appears across 2 boiler brands and 9 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is not receiving electrical power or has an internal blown fuse, meaning it cannot start the ignition process. (As reported on Glow-worm Ultimate3)

Pick your boiler brand for the neon 1 not lit fix

Glow-worm neon 1 not lit 7 models Saunier Duval neon 1 not lit 2 models

Source

Information for the neon 1 not lit 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