Your heat pump has detected a problem with a temperature sensor inside the unit, causing the system to stop working to prevent any damage.

Plate Heat Exchanger Inlet Refrigerant Thermistor (T2B) Error

What causes this fault?

This fault occurs when the system loses its ability to accurately measure the temperature of the refrigerant as it enters the heat exchanger. This usually happens because the internal sensor has developed an electrical fault or the wiring has become loose or damaged, preventing the main control board from monitoring the unit's safety and efficiency.