BoilerFaultCodesYour boiler has detected that the connection to the sensor monitoring exhaust fumes has been broken or lost, causing the system to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The flue gas temperature sensor contacts have been interrupted
What causes this fault?
This fault occurs when the boiler's control board can no longer communicate with the sensor that monitors the temperature of the exhaust gases. The most common reason is that the delicate electrical pins on the sensor have corroded or the wiring has vibrated loose over time. Because the boiler cannot verify that the fumes are at a safe temperature, it shuts down immediately to prevent damage to the internal plastic components.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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