High
E9 318 on Worcester Bosch Danesmoor

Your boiler has shut down because it can no longer detect the temperature of the exhaust gases, usually due to a loose wire or a faulty internal sensor.

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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