High
F5 on Ferroli Tempra 12 18

Your boiler has detected an issue with its internal airflow system that prevents it 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

The air pressure switch is stuck in the closed position. Check the air pressure switch and the fan wiring.

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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