High
Neon 3 lit on Saunier Duval Xeon 30ff

Your boiler is failing to detect the airflow needed for safe operation, likely due to an internal electrical connection issue or a faulty main control board.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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 3 lit? NO: Is there 230V~ between "N/C" on air pressure switch and N? NO: Check yellow cable between printed circuit board and air pressure switch. If satisfactory replace printed circuit board.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

Neon 1View →Neon 2View →

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