High
F15 on Ferroli Optima 201

Your boiler has detected that the internal fan responsible for safely venting exhaust gases is not spinning correctly or has lost its connection.

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 (Tachometer signal interrupted, fan connection / Fan damaged, debris in fan)

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

F37View →

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