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HVAC-Cx Building HVAC Systems Commissioning Tool

HVAC-Cx Faults

HVAC-Cx is a semi-automated commissioning software tool designed to facilitate performance analysis for heating, ventilating, and air conditioning (HVAC) mechanical equipment in buildings. It can be used for functional performance testing (FPT) and ongoing monitoring.  It provides the ability to detect faults related to improper operation, using expert rules to present results of the most likely fault causes and to assist in documenting results. The goal is to improve the system performance in terms of occupant comfort, energy management and equipment life. It was conceived exclusively for commercial buildings equipped with one or more air handling units (AHUs), terminal units, hot and chilled water loops, and chillers. The commissioning methods developed can be applied to several types of equipment and custom rules can be introduced.  The structure includes future expansion capabilities for the analysis of boilers and other common mechanical equipment.

HVAC-Cx aids building operators in decision-making by analyzing data collected from the building energy management system (BEMS) and evaluating the data using a set of expert rules governing the proper operation of the mechanical equipment.

HVAC-Cx software has many useful features, in particular:

  • It can analyze large amounts of data collected from BEMS;
  • Fault detection is applied using expert rules for AHUs, chiller loops, and terminal units;
  • Simplified results are presented in the forms of graphs and tables; and
  • Diagnostic assistance is provided through a list of possible causes for each fault detected.

Sample Screenshots

HVAC CX 2.3 Screenshot
HVAC CX 2.3 Screenshot2
Created June 22, 2017, Updated November 15, 2019