High
LED1 on on Ferroli Combi 77 FF Popular

Your boiler has detected a failure with the safety system that handles smoke and fumes, preventing it from firing up for your safety.

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

N/C contact of air pressure switch should be closed between 67-66 of P.C.B.

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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