What is the low stage compressor suction pressure in a two-stage package system?

In a two-stage package refrigeration system, the low stage compressor operates under relatively low suction pressures compared to the high stage compressor. The low stage is responsible for drawing in refrigerant vapor that has a lower temperature and pressure, which is typically associated with the evaporator temperature range for cooling applications.

A common range for low stage suction pressure in such systems usually falls between 5" HG to 15" HG, with 9" HG being a typical and commonly acceptable value. This pressure allows for efficient refrigerant vaporization and proper function of the low stage compressor, ensuring that the system effectively manages heat absorption.

Understanding these pressures is crucial for maintenance and troubleshooting in industrial refrigeration systems, as deviations from these values can indicate issues such as overloading, insufficient refrigerant, or malfunctioning components. Thus, the selection of 9" HG reflects a common operational set point for effective performance in typical two-stage refrigeration package systems.