Your boiler has detected an electrical fault with the internal sensor that monitors water temperature, causing the system to stop working for safety.

Flow sensor short circuit – check connections to flow sensor

What causes this fault?

This fault occurs when the boiler's internal computer receives an incorrect electrical signal from the sensor that monitors hot water leaving the unit. The most common reason is that the sensor has suffered an internal electrical failure or the delicate wiring connecting it to the main control board has become damaged or loose.