High
E28 on Baxi Duo-tec Combi

Your boiler has detected an issue with the sensor that monitors the temperature of the gases leaving your flue, meaning it has shut down as a precaution to ensure it is operating safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Flue NTC Fault

Engineer required

This is a high 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

E50View →E110View →

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