High
C LED 7 on Ferroli Optima 201

Your boiler has detected an issue with the airflow system which prevents it from safely igniting and providing heating or hot water.

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 (16) not running at full speed or - air flow too low: - air pressure switch (43) faulty

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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