Your boiler has lost its connection to the sensor that monitors the heating temperature, causing the system to stop running to prevent damage.

Temperature sensor from radiator error – electronic card detecting a failure.

What causes this fault?

This fault occurs when the boiler's main internal computer loses communication with the sensor that monitors the temperature of the water sent to your radiators. The most common reason is a simple failure of the sensor's internal components or a loose connection in the wiring that links the sensor to the control board. Without an accurate temperature reading, the boiler shuts down as a safety precaution to prevent the system from overheating.