What is the most common metering device in reciprocating commercial refrigeration systems with a capacity of under three tons?

The most common metering device in reciprocating commercial refrigeration systems with a capacity of under three tons is the thermostatic expansion valve (TEV). TEVs are widely used in refrigeration systems because they automatically adjust the flow of refrigerant based on the cooling demand. This adaptability allows for improved efficiency and better temperature control within systems that operate in varying load conditions.

In systems under three tons, where precise control and efficient operation are crucial, TEVs can respond to changes in temperature and pressures, optimizing the refrigerant flow to match the cooling requirements. This capability helps maintain ideal evaporation temperatures, which is vital for overall performance in smaller commercial applications.

While other metering devices, such as expansion valves and electronic expansion valves, do exist, TEVs are favored in this specific context due to their proven reliability and effectiveness in low-capacity systems. The capillary tube, on the other hand, is simpler and typically used in smaller, low-cost applications, but it does not offer the same level of control as a thermostatic expansion valve, making TEVs the optimal choice in many commercial refrigeration scenarios.