Emergency
E53 on Baxi 400 Combi (range)

Your boiler has detected an issue with the air supply or how the gas is burning, meaning it cannot operate safely and has shut down.

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

Poor combustion – flue terminal may be blocked

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

E20View →E28View →E55View →

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