Halstead NEON 1 Fault Code
Also written as NEON1 — same fault.
The Halstead NEON 1 fault code means: your boiler is correctly receiving power and is in standby mode, awaiting a signal to provide heating or hot water.. It appears on 1 Halstead model in our database.
Technical description: MAINS ON
DIY fix possible
Check that your room thermostat is set to a higher temperature than the current room temperature.Ensure your hot water timer or programmer is set to 'on'.Check that the boiler's own selector switch is set to the heating or water position.
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Gas Safe Register →Halstead models that show the NEON 1 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Halstead NEON 1 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