Centrifugal compressors are used in many applications including pipeline transport of natural gas along with many other related applications including vapor compression refrigeration. Centrifugal compressors have different operating limitations than the reciprocating compressor, the scroll compressor, and the rotary compressor. The centrifugal compressor has an operating range where it operates efficiently however outside of this range, either the over or under that operating range, is basically useless. Other issues make them not ideal for use in certain applications because of the operating range issues. Centrifugal compressors, like rotary screw compressors, are used in chillers for chilled water applications. Many of the chiller providing large tonnage applications where the compressor can meet the operating range necessary to remain efficient and operate in a safe operating range. The centrifugal compressor uses centrifugal force to sling the vapor refrigerant outward to increase the refrigerant pressure and the temperature and then sends it to either condenser coils or a condenser barrel where the heat is removed from the refrigerant.