BoilerFaultCodesYour boiler has detected an issue with the sensor that monitors the temperature of the exhaust gases, causing the system to shut down as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: FLUE THERMISTOR ERROR
What causes this fault?
This fault occurs when the control board loses communication with the sensor that monitors the temperature of the gases leaving your chimney. The most common reason is that the sensor itself has developed an electrical fault or the wiring connecting it to the main board has become damaged or loose. Because this sensor is a critical safety component designed to prevent the boiler from overheating, the system will shut down immediately to protect the appliance.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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