How much does it cost to fix Alpha error code Neon D NOT illuminated?

Typical repair cost for the Alpha Neon D NOT illuminated fault is £100-300 including labour.

Neon D NOT illuminated High

Alpha Neon D NOT illuminated Fault Code

Q: What does the Alpha Neon D NOT illuminated fault code mean?

Your boiler has no power, meaning it cannot start up to provide heating or hot water because it is not receiving any electricity.

Also written as NEONDNOTILLUMINATED — same fault.

The Alpha Neon D NOT illuminated fault code means: your boiler has no power, meaning it cannot start up to provide heating or hot water because it is not receiving any electricity.. It appears on 1 Alpha model in our database.

Technical description: Check electrical supply, fuses, or PCB fault

Typical repair cost £100-300 (including labour)

DIY fix possible

Check your consumer unit to see if the boiler's circuit breaker has trippedEnsure the fused spur switch located near the boiler is turned onCheck the fuse inside the fused spur switch to see if it has blown

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Alpha models that show the Neon D NOT illuminated fault code

Click a model for the full fault code list and model-specific repair notes.

CD C Repair: £100-300

Source

Alpha Neon D NOT 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