Which component controls a thermal electric (solid-state) expansion valve?

The component that controls a thermal electric (solid-state) expansion valve is a NTC thermistor. This type of thermistor is sensitive to temperature changes; as the temperature around it varies, its resistance changes accordingly. The NTC (negative temperature coefficient) thermistor decreases its resistance when the temperature increases. This characteristics enable it to accurately detect the temperature of the refrigerant in the system, providing critical feedback to the electronic control unit that manages the expansion valve's operation.

In the context of a thermal electric expansion valve, this feedback is essential for optimizing the cooling or heating processes in HVAC systems by enabling precise adjustments to refrigerant flow based on the current temperature, ensuring efficient performance and energy use.