How much does it cost to fix boiler error code Neon 3 NOT lit?

Typical repair cost for the boiler Neon 3 NOT lit fault is £120-300 including labour.

Neon 3 NOT lit High

Boiler Fault Code Neon 3 NOT lit

Also written as NEON3NOTLIT — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code Neon 3 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 has stopped working because it cannot confirm that the internal fan is safely clearing waste gases from the system. (As reported on Glow-worm Space Saver 30 40 50)

Pick your boiler brand for the Neon 3 NOT lit fix

Glow-worm Neon 3 NOT lit 7 models Saunier Duval Neon 3 NOT lit 2 models

Source

Information for the Neon 3 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