Emergency
E53 on Baxi Suprima 50

Your boiler is not getting enough air to burn gas safely, which often means the external exhaust pipe is obstructed.

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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