High
Neon 3 not lit on Ikon 40-50 CI

Your boiler has detected an issue with the ventilation system and has shut down as a safety precaution to ensure exhaust gases are being cleared correctly.

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.

What the manual says

Manufacturer manual

Air flow proving fault - that is fan or air pressure switch - see detailed fault finding chart.

From this model's manual
Verified against the Ikon 40 50 Ci installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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