Frick Screw Compressors Pt. 2

Here, the focus is on screw compressors in refrigeration and the use of economizers and side loads to enhance energy efficiency. The advantages of screw compressors over reciprocating compressors are highlighted, particularly their ability to have a secondary suction port for drawing additional vapor. The economizer utilizes this port to sub-cool liquid going from the condenser to the evaporator, resulting in colder liquid for better efficiency.

Side loads involve feeding evaporated vapor from a secondary evaporator back to the economizer port. Learn the benefits of economizers in terms of improved refrigeration effect and efficiency gains, with specific examples and efficiency curves provided. The combination of economizers with variable frequency drives (VFDs) is also discussed as a means of achieving efficiency throughout the entire load range.

We conclude with information on economizer BI control, which adjusts the volume ratio for compressors with economizers, resulting in significant energy savings. An overview of Johnson Controls’ compressor packages, including standard models and those compatible with VFDs, is provided.