High
F1 on Ferroli Optimax

Your boiler is not lighting, which means it cannot provide heat or hot water because the burner is failing to ignite.

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

No burner ignition. Possible causes: No gas; Detection or ignition electrode fault; Defective gas valve; Incorrect inlet gas pressure; Siphon obstructed.

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

F2View →F4View →A01View →

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