Emergency
A04 on Ferroli Optima 201

Your boiler has detected an issue with its exhaust system multiple times, so it has safely shut itself down to prevent any unsafe gases from building up.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

Flue gas fault (Fault F07 happened 3 times in the last 24 hours)

Engineer required

This is a emergency 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

F07View →

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