Emergency
F04 on Ferroli Arena 30A

Your boiler has detected an issue with its exhaust system multiple times today and has locked itself out to keep your home safe.

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 safety thermostat intervention (after 3 times in 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

F05View →F37View →

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