High
A05 on Ferroli Optimax

Your boiler has stopped working because use the fan that safely clears exhaust fumes is not communicating correctly 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 for 1 hour or longer)

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

A04View →A06View →

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