MSC Retro-Commissioning Project
A local engineering firm contacted MSC about a client that had been experiencing multiple problems with various mechanical systems throughout their facility. Costly repairs, emergency service calls, equipment replacements, and downtime were out of control, and the various fixes simply weren’t working. MSC was called in to take a holistic look at building systems and perform retro-commissioning.
Retro-commissioning is the application of the commissioning process to existing buildings in order to improve how mechanical, electrical and controls systems function interactively to enhance overall building performance and lower energy costs. Facilities that have had additions, renovations, equipment replacements, repairs, band-aid fixes and other changes that cause systems to drift from original design intent benefit most from retro-commissioning. Mot repairs and improvements can be made relatively inexpensively along the way, and many can be accomplished through controls changes alone.
To begin the retro-commissioning process, MSC met with facility managers and operators to walk down, investigate, and document all of the problems and anomalies, both system by system and as a whole. All information and documentation from this discovery and interview phase was thoroughly reviewed and a plan of control was written in detailed sequence. Next, technicians set up data loggers to read temperature and humidity throughout the facility and created trend logs on the BAS system to see how systems were performing and delivering around the clock. Air and water readings, combined with a review of the sequence of operation, quickly revealed a number of problems.
The building owner was involved in all steps of the retro-commissioning process and was kept fully up-to-date on MSC’s progress. Numerous repairs and changes were made along the way to immediately correct glaring problems that had existed for some time. Specialty instruments including an ultrasonic flow meter and various Fluke recorders were used to take critical readings. MSC corrected water flow and air flow problems in a phased approach, along with various control and electrical issues on variable frequency drives.
Analysis of sequence of operation uncovered a variety of issues, and applied corrections brought excellent results. Calibration or replacement of various field instruments, or adding new instruments where they were needed, yielded accurate data that helped MSC technicians make corrections for optimal system performance. Refrigeration problems were identified and corrected to prevent future loss of compressors, a costly problem that had dogged the facility for years.
Teaming with building owners and facility personnel during commissioning is a key factor in ensuring a good understanding of a building systems, how they should run, and how they should be maintained in the future. Together, MSC and owner put together new SOPs to keep systems running smoothly.
Typical energy savings after retro-commissioning range from 10-20% of total building energy costs. This facility was no exception, with highly-satisfied owners reporting an immediate 17% reduction in utility bills.