8.2. Technical Trends in Large Compressors
The current technical development of large compressors for heating, ventilation, air conditioning, and refrigeration (HVAC&R) applications is focused on improving overall efficiencies, maintaining a wide operating range, and shifting to next-generation low global warming potential (GWP) refrigerants.
In the past, centrifugal and reciprocating compressors were the mainstream large compressors for HVAC&R applications. During the 1980s, semi-hermetic screw compressors in capacities of 40-300 tons were developed and replaced reciprocating compressors and some small centrifugal compressors in chiller applications.
With the advent of a new oil-free centrifugal concept, small centrifugal compressors extended their capacity into the range of screw compressors. From the other direction, the development of larger scroll compressors up to 60 hp has also extended their capacity into the range of screw compressors.