BoilerFaultCodesYour boiler has shut down because it cannot accurately measure the temperature of the exhaust gases, causing the burner to stop 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: Burner blocked - Flue gas temperature sensor break
What causes this fault?
This fault occurs when the boiler's control board loses communication with the sensor that monitors the heat of the exhaust gases. The most common reason is a physical break in the sensor's internal circuitry or a loose connection in the wiring harness. For safety, the boiler shuts down because it can no longer verify that the exhaust temperatures are within safe limits.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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