Halstead Neon L1 Fault Code
Also written as NEONL1 — same fault.
The Halstead Neon L1 fault code means: your boiler is connected to the electricity supply and is waiting for a request to provide heating or hot water, so everything is working exactly as it should.. It appears on 1 Halstead model in our database.
Technical description: Stand-by / Power on indicator
DIY fix possible
No action is required as this is the normal standby lightTurn on your central heating or hot water at the programmerCheck your thermostat settings to ensure heat is requested
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Gas Safe Register →Halstead models that show the Neon L1 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Halstead Neon L1 fault code information on this page is sourced and cross-checked against the official Halstead service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026