INTRODUCTION
Objectives
The objectives of commissioning during construction focus on realizingenergy and life-cycle cost expectations through the proper installation of criti- cal systems and components. Proper planning will deliver the project on time and on budget and provide opportunity to properly commission the refrigera- tion system(s). This chapter provides guidance to ensure that each installed system is commissionable and will achieve the goals defined in the Owner’s Project Requirements (OPR). Owners of refrigeration systems are encouraged to incorporate a commissioning plan into their projects as described in Chap- ter 2, and each project team should use the steps in this chapter to prepare an installation for commissioning activities.
Key areas on which to focus commissioning efforts during construction include procurement of the refrigeration equipment and proper installation of the refrigeration piping and energy management systems (EMSs). Proper pro- curement of equipment ensures that the specifications are met, that submittals match the construction document (CD) requirements, and that the commis- sioning intent of the design can be carried out. Proper installation of piping and EMSs enables the commissioning authority (CxA) to fully perform the functions detailed in the Commissioning Plan and ensures a clean handoff to the Start-Up and First-Year Operation Phase of the project. Many commis- sioning opportunities may be missed if a step is overlooked or if the quality of the installation isn’t monitored. Commissioning during the Construction and Installation Phase of a project allows the owner the opportunity to operate the refrigeration system at a more efficient level and ensures long-term reliability and efficiency.
Process
The Construction and Installation Phase of a refrigeration project imple-ments the scope as outlined in the OPR, Basis of Design (BoD), and CDs and prepares the project for start-up and final commissioning. The following items should be commissioned or involve commissioning activities during this phase: • Project plan review, prebid conference, requests for information
Refrigeration Commissioning Guide for Commercial and Industrial Systems
• Negotiation/bidding for prime contractors and subcontractors • Procurement requirements of refrigeration equipment and controls,
including the EMS, as well as review and acceptance at delivery • Assembly of the construction team and project schedule planning • Installation of the refrigeration system, including display cases,
compressor racks, condensing units, controls (including EMS), inter- connecting piping, electrical wiring, and other related components • Various testing and installation verifications
• Pre-start-up quality control (QC) and readiness • Installation final commissioning and review
Figure 3-1 details activities related to commissioning during the Con- struction and Installation Phase. Activities may vary depending on the nature of the project.
Roles and
Responsibilities
Table 3-1 shows an example of commissioning roles and responsibilities during the Construction and Installation Phase. This table is an example of an owner-specified project where the owner provides a substantial portion of the requirements and specifications to the designers and contractors (as opposed
“FORGOTTEN” INSTALLATION ISSUES
Seemingly minor omissions or errors during equipment installation can lead to significant problems and/or inefficiencies that can last for the life of the facility.
Example: Most low-temperature display cases require wiring to transfer a signal from the
case to the energy management system (EMS) to terminate the defrost cycle when the evaporator is free of frost (rather than running the full default period for the defrost cycle). If this wiring is specified in the CDs but is overlooked during equipment installation, the defrost cycle may run longer than it should, increasing energy consumption, potentially risking product integrity, and possibly creating other problems. It is relatively effortless to run this wiring during equipment installation, but running the wiring after the store opens is much more difficult as it can disrupt sales and/or interfere with other maintenance operations. The owner may not even allow the work to be done, especially during the busy days or weeks following the grand opening. As a result, this problem could go uncorrected for the life of the equipment.
Associated Costs: In an example where a supermarket has three runs of glass-door frozen
food/ice cream cases with 30 doors in each run, the total defrost electrical load is 63 kW. The defrost runs on average 15 minutes longer each day because the termination wiring was not installed. If the power cost is $0.10/kWh, the additional costs each year for this single omission would be $575.00.
63 kW/day × 0.25 h/day × 365 days/yr = 5749 kWh/yr 5749 kWh × $0.10/kWh = $575.00/yr
Translating this to grocery sales equivalent means that a store would have to sell an addi- tional $34,000.00 worth of groceries to cover this cost!
When coupled with other possible oversights, the annual costs of overlooked installation issues can grow significantly and continue for the life of the facility.
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Table 3-1 Example of Roles and Responsibilities Matrix
in the Construction and Installation Phase for an Owner-Specified Project
Role Responsibilities in the
Construction and Installation Phase
Owner or Owner’s Representative
• Review, approve, and disseminate any changes in BoD, OPR, Commissioning Plan, CDs, sequence of operations (SoO), and systems manual and accept deliverables. • Determine what method will be used to commission the
project.
• Remain involved throughout the process, including scheduling, project management, interfacing with the CxA, contractors scheduling, equipment procurement, etc.
Commissioning Authority (CxA)
• Communicate Commissioning Plan to the construction team so all are aware of the commissioning structure. • Make site visits and inspections and provide
documentation of the inspections as required in the Commissioning Plan.
• Review OPR, BoD, CDs, SoO, and product/equipment specifications.
• Communicate changes discovered during the commissioning process as relates to the BoD, OPR, Commissioning Plan, CDs, and SoO. Escalate deviations to the owner so that appropriate action is taken to correct any deficiencies that do not have prior approval.
Refrigeration Designer (Engineer of Record)
• Provide updates or changes in BoD, CDs, and SoO that occur during the requests for information (RFI) or construction process.
• Review and approve product/equipment submittals.
Refrigeration Contractor and/or Installer
• Provide feedback to the design team on the project documents where conflicts exist or field modifications are required.
• Review systems manual so that the installation is executed in concert with the commissioning requirements.
• Resolve issues and update issues log, documenting what actions were taken, when each item is complete, and whether the issue is closed.
• Install refrigeration systems per the OPR, BoD, and CDs, ensuring that the completed system can be commissioned. Record testing events and provide evidence to the CxA that all pertinent criteria have been met.
Refrigeration Original Equipment Manufacturers (OEMs)
• Supply equipment per the CDs and the project schedule requirements.
• Provide operation and maintenance information for the systems manual.
• Participate in any on-site inspections after equipment arrives on site as required in the owner’s equipment solicitation.
Control System Contractor
• Install controls per the CDs.
• Ensure that all controls can be commissioned as defined in the CDs.
Controls Systems Programmer
(if Required by Owner)
• Provide EMS programming to support the refrigeration and HVAC equipment as defined in the CDs.
• Coordinate with the OEM programming that may be included and shipped as part of the refrigeration or HVAC systems. Facility Operations and
Maintenance Staff • Provide input on site information, OPR, and BoD. Refrigeration Commissioning Guide for Commercial and Industrial Systems
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to a design-build project, where the owner may provide minimal detail in the requirements). An example of a full roles and responsibilities matrix for all phases in one table is provided in Appendix A.