Your boiler has detected a problem with the sensor that monitors the temperature of the water flowing through your radiators, which prevents the heating from running correctly.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: Fault on Central Heating Sensor
What causes this fault?
This fault occurs when the internal sensor responsible for tracking the temperature of your heating water becomes faulty or loses its connection. The most common reason is that the electrical resistance inside the sensor has drifted out of its normal range due to age or internal wear, meaning it can no longer send an accurate signal to the boiler's control board.
This fault is often noticed during the first cold spell of autumn when the heating system is switched back on after being idle all summer.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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