High
E9 210 on Worcester Bosch 26 CDi Xtra

Your boiler has detected that the exhaust gases are too hot or a safety sensor has broken, causing the system to shut down for your protection.

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

The temperature measured by the flue gas sensor is too high and is open

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

E9 224View →E2View →

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