BoilerFaultCodesTechnical description
Permanent fault. Flue temperature sensor short-circuited, sensor not or badly connected, bad connection or sensor fault.
What causes this fault?
This fault occurs when the boiler's internal safety system detects an irregular electrical signal from the sensor monitoring the heat of the exhaust gases. The most common reason is that the sensor has developed a physical defect or the wiring connecting it to the main control board has come loose or been damaged. Because the boiler can no longer accurately monitor flue temperatures, it shuts down to prevent any risk of overheating.
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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