Boiler Fault Code FAN NEON

Also written as FANNEON — same fault.

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

Fault code FAN NEON 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 The indicator light is showing that your boiler's internal ventilation fan is active, which is a normal part of the startup and shutdown sequence. (As reported on Halstead Hero)