Engineered Systems, Jul. 2014, by Gary Hamilton. (Free registration required to view full-text.)
http://www.esmagazine.com/articles/96638-chiller-retrofits-in-health-care-facilities

"One of the worst things you can do is note the capacity and replace the chiller. Have the building loads and usage changed? What about motors and cooling towers? Consider these and your part-load realities to create real long-term improvements."