Emergency
E53 on Baxi Suprima 80

Your boiler is not getting enough air to burn gas safely, which could be caused by an obstruction in the external vent or a component failure.

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 →E55View →

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