High
46 on Johnson Starley C16u

Your boiler has shut down because it cannot detect the sensor that monitors the temperature of the exhaust gases.

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 gas temperature sensor open circuit. Temperature sensor not connected or failed

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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