Project Profile: Book Development Project

Engineering firm: FST Technical Services
2024 Commissioning Giants rank: 11
Project: Book Development Project
Location: Detroit, MI, United States
Building type: Mixed use
Project type: New construction
Engineering services: Commissioning, retro-commissioning
Project timeline: August 2020 to May 2023
Commissioning budget: $188,800

Challenges

FST provided commissioning services from the design phase to the post-acceptance phase, during the commissioning process FST found several deficiencies. Here are some of the examples:

1. During functional testing of water source heat pumps, the FST team discovered that several units were not operating according to the designed sequence of operations. These units were not effectively heating or cooling their respective zones as expected. Upon investigation, FST and the project team found that many of the units’ compressors were not starting, which was causing the units to fail to operate as designed.

2. FST discovered that several water source heat pumps were not changing over between heating and cooling modes based on zone temperature needs. While troubleshooting, many units were found programmed via the building management system (BMS) to remain in either heating mode or cooling mode, rather than auto mode. This setup limited the units’ ability to switchover between modes to maintain the desired zone temperature setpoints effectively.

3. FST identified that a water source heat pump in one of the restaurant spaces was not adequately maintaining the required discharge air temperature to its associated variable air volumes (VAVs) for effective heating or cooling in the respective zones. According to the design, the heat pump’s discharge air temperature was supposed to be based on the average of the zone temperature setpoints for its five associated VAVs—three of which serve the restaurant and two the kitchen space. This mismatch in setpoints led to the heat pump short cycling, causing rapid fluctuations in compressor activity as it struggled to provide sufficient heated air to the restaurant’s VAVs and cooled air to the kitchen’s VAVs.

4. During FST’s review of the BMS graphics, several discrepancies were identified. Various pieces of equipment from different systems within the building were either absent from the BMS room layout or incorrectly mapped within the layout. This misrepresentation of equipment posed challenges for the building operations and engineering team as the BMS was not monitoring and controlling the systems effectively.

5. The FST team found that the tap cables within several transformers were arranged with inadequate spacing between phase-to-phase and phase-to-ground cables. This issue posed electrical safety risks and could have negatively impacted transformer performance.

Solutions

FST was able to help correct the deficiencies found throughout the building, below are the solutions for each deficiency listed above:

1. After identifying the units with compressor issues, FST and the project team identified several compressors that were found to be faulty and required replacement by the manufacturer. The other compressors were removed from their units, troubleshooted, reinstalled, and successfully re-tested without further issues.

2. Through the collaborative efforts of FST, the controls contractor, master system integrator, and the building operations and engineering team, the issue was resolved by configuring and setting all water source heat pumps to operate in auto mode. These units were then re-tested to confirm proper automatic changeover between heating and cooling modes.

3. The project team and FST held multiple meetings with the design team to assess whether the issues were due to mechanical system faults or design problems. After careful evaluation, the team concluded that the sequence of operations for the water source heat pump needed revision. As part of the revisions, one significant update involved altering the discharge air temperature reset schedule. The new approach based the schedule on outside air temperature rather than the average zone temperature setpoints of the associated VAVs. After implementing the revised sequence, further design issues emerged, prompting a redesign of the system in the restaurant space. The redesign includes adding equipment to isolate zones, thereby enhancing system efficiency, and improving occupant comfort.

4. Using the communication drawing sets provided by the controls contractor, FST collaborated with the master system integrator to add and verify equipment locations. Through this joint effort, FST was able to confirm the accurate placement of all equipment and ensure that thermostats and other control devices were correctly labeled and positioned. This process resulted in a clear building layout for the building operations and engineering team, enabling them to easily identify and address equipment and system issues.

5. FST collaborated with the electrical contractor to gather manufacturer documentation and verify the arrangement of each tap cable according to recommended spacing standards. Following the necessary adjustments to the tap cable spacing, the transformers were inspected and successfully passed prior to energization. After being energized and connected to their respected systems, the transformers underwent a final inspection and passed without any issues.

Learn more about this project.

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