Emergency
E03 on Alpha CD24

Your boiler has detected an issue with the ventilation system that clears away exhaust gases, so it has automatically shut down for your safety.

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 thermostat/Flue pressure switch intervention

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

E04View →E06View →

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