High
F5 on Ferroli Tempra

Your boiler has detected that a safety sensor is stuck, preventing the fan from safely venting exhaust gases and stopping the boiler from firing up.

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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Related fault codes

F4View →

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