High
45 on Johnson Starley C10d

Your boiler has detected an electrical fault with the sensor that monitors the exhaust gas temperature, causing it to shut down for safety.

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 short circuit. Short circuit in wiring between sensor and control board. Check wiring to sensor. Check electrical resistance of the sensor.

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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