BoilerFaultCodesTechnical 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 that the sensor has physically failed or developed a break in the internal wiring, though it can also be triggered if the sensor has become dislodged from its mounting clip. For safety, the boiler shuts down immediately to ensure the exhaust system does not overheat.
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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