What type of metering device is used in a flooded evaporator to maintain the proper level of liquid refrigerant?

In a flooded evaporator system, maintaining the correct level of liquid refrigerant is crucial for optimal performance and efficiency. A low side float is designed to control the flow of refrigerant into the evaporator based on the liquid level present. When the liquid level rises to a certain point, the float activates and helps regulate the refrigerant flow, ensuring that an adequate amount of liquid is available for evaporation while preventing overflow.

This mechanism is essential for flooded evaporators, where the goal is to keep the evaporator fully charged with refrigerant. The low side float's function helps to ensure that the evaporator operates efficiently and avoids issues like flooding or starvation of refrigerant, both of which could lead to performance problems.

In contrast, other devices such as capillary tubes and automatic expansion valves (AEVs) serve different purposes. Capillary tubes are fixed metering devices that do not adjust based on liquid level, while AEVs are designed for systems where variable load conditions require a responsive metering action but are not specifically utilized in flooded applications. The high side float is typically used in specific circumstances pertinent to high-pressure sides of systems rather than directly managing refrigerant levels in a flooded evaporator.