BoilerFaultCodesYour boiler has detected a problem with the sensor that monitors the temperature of the exhaust gases, 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: Flue thermistor fault
What causes this fault?
This fault occurs when the control board loses communication with the sensor that monitors the heat of the exhaust gases. It is usually caused by the sensor failing due to age or the electrical wiring connecting it to the main board becoming loose or damaged. For safety, the boiler shuts down immediately to ensure the exhaust temperature doesn't exceed safe limits.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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