Alpha Neon C illuminated Fault Code
Also written as NEONCILLUMINATED — same fault.
The Alpha Neon C illuminated fault code means: your boiler is operating normally and the burner is currently lit, which is exactly what should be happening when you have the heating or hot water turned on.. It appears on 3 Alpha models in our database.
Technical description: Burner lit
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Alpha models that show the Neon C illuminated fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Alpha Neon C illuminated fault code information on this page is sourced and cross-checked against the official Alpha service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026