Your boiler's hot water sensor has stopped working correctly, meaning your taps might not deliver hot water as expected.

What causes this fault?

This fault occurs when the internal sensor responsible for monitoring your hot water temperature fails or sends an incorrect signal to the boiler's computer. The most common reason is natural wear and tear or internal corrosion on the sensor's metal tip, which prevents it from accurately measuring heat levels. In some cases, the thin electrical wires connecting the sensor to the main control board may have become loose or damaged.