Which of the following is not a main type of automatic refrigerant flow control?

The condenser equalizer valve is not classified as a main type of automatic refrigerant flow control. In refrigeration systems, the primary automatic refrigerant flow control devices include the expansion valve, capillary tube, and thermostatic valve.

The expansion valve regulates the flow of refrigerant into the evaporator based on the cooling demand, allowing for precise control over the refrigerant flow according to system conditions. The capillary tube serves as a simple metering device that creates a pressure drop for refrigerant flow, suitable for low-capacity systems. The thermostatic valve adjusts the flow based on the temperature, thus optimizing performance based on load variations.

In contrast, the condenser equalizer valve is associated with the pressure equalization in the condenser but does not directly control the flow of refrigerant in the same manner as the other devices mentioned. It is more of a support component in the system rather than a primary control mechanism. Understanding the roles of these various components is essential in the context of refrigeration systems, as it helps in diagnosing issues and designing systems effectively.