The use of multiple chillers in a plant is a common practice resulting from original design in some cases and from growth of a facility in other cases. The load presented to a chiller plant is a large factor in how the plant must be operated to meet the load. However, the selection of which chiller to use and how much load on each chiller can have a significant influence on the operating cost to meet a given load. This paper examines methods of establishing part load energy characteristics for individual chillers, and using an analysis of these to better control multiple chiller plants.

Units: I-P