High
E9 318 on Worcester Bosch 30i Junior

Your boiler has sensed that it is getting too hot and has shut itself down as a safety precaution to prevent damage.

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 219View →E9 224View →

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