Neon 1 High

Saunier Duval Neon 1 Fault Code

Also written as NEON1 — same fault.

The Saunier Duval Neon 1 fault code means: your boiler is not receiving any electricity, which means it has completely shut down and cannot heat your home or water.. It appears on 2 Saunier Duval models in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Is neon 1 lit? NO: Correct power supply problem.
Typical repair cost £90-200 (including labour)

DIY fix possible

Check that the boiler power switch or fused spur next to the unit is turned on.Check your home's main consumer unit (fuse box) to see if a trip switch or fuse has blown.Plug a small appliance into the wall socket used by the boiler to confirm that the socket itself is providing power.

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Saunier Duval models that show the Neon 1 fault code

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

Source

Saunier Duval Neon 1 fault code information on this page is sourced and cross-checked against the official Saunier Duval service / installation manuals for each affected model.

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