High
E9 318 on Worcester Bosch Junior 24i

Your boiler has shut down because a safety sensor has detected that the exhaust gases are getting too hot or the sensor itself has lost its electrical connection.

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 flue gas temperature sensor contacts have been interrupted

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 →

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