High
F5 on Ferroli Optimax

Your boiler has detected an issue with the fan that is responsible for clearing exhaust gases, preventing the unit from starting safely.

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

Fan problem. Possible causes: Tachometer signal interrupted; Fan damaged.

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

A03View →F15View →

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