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Performance Monitoring of Chilled Water Distribution Systems using HVAC-Cx



Natascha S. Milesi-Ferretti, Michael A. Galler, Steven T. Bushby


Automated commissioning tools facilitate an ongoing commissioning process to improve occupant comfort, ensure the persistence of correct system operation, and reduce energy consumption. These tools decrease the time and the skill level required to carry out necessary quality assurance measures, and as a result they enable more thorough testing of building heating, ventilating, and air-conditioning (HVAC) systems. The purpose of the research effort described in this paper is to develop, test and demonstrate an automated commissioning tool that can perform active testing and then analyze results to detect common mechanical faults and control errors in chilled water loops (chiller loops). This paper presents the newest extension of the HVAC-Cx software, a tool developed by the U.S. National Institute of Standards and Technology (NIST). It describes the algorithm used to analyze chiller loops and presents the results of an investigation using field data obtained from a building automation system, comparing the actual performance of the installed system against a set of expert rules for the system. This paper examined the effectiveness of the tool in detecting faults and documents the initial results from the first field trial.
ASHRAE Transactions
123, Part 2


HVAC, Commissioning, BACnet, Chilled water, performance monitoring


Milesi-Ferretti, N. , Galler, M. and Bushby, S. (2017), Performance Monitoring of Chilled Water Distribution Systems using HVAC-Cx, ASHRAE Transactions, [online], (Accessed April 15, 2024)
Created July 30, 2017, Updated September 18, 2017