- magnetic bearings
- improved compressor aerodynamics
- new heat exchanger designs
These new improvements require the chilled water system to be evaluated more extensively since chillers are nearing the efficiency limit. One of the many system modifications that has the ability to improve efficiency greatly, is the use of a chiller piping strategy called “Series Counter-Flow (SCF)”. This document evaluates the impact of SCF on efficiency while keeping in mind what it requires on the building controls side as well as plant design (piping arrangement). This document will be directed toward water-cooled centrifugal chillers predominately but is not limited to centrifugal chillers.