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 safety system detects an irregular electrical signal from the sensor that monitors the heat of the exhaust gases. The most common reason is that the sensor has developed an internal electrical short or the wiring connecting it to the main control board has become loose or damaged. In some cases, it can be triggered if the heat exchanger is extremely dirty, causing exhaust temperatures to exceed safe limits.
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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