High
F15 on Ferroli Optimax

Your boiler has stopped working because the fan that removes exhaust fumes is not spinning correctly or cannot communicate with the 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

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

F14View →

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