The following primary commissioning activities (in approximately sequential order) address commissioning objectives. The CxP coordinates and ensures that all activities occur and perform successfully.
Bidding and Contract Negotiation. A member of the commissioning team (usually the CxP) may attend the prebid conference to present an overview of commissioning requirements and answer questions. Changes that occur during bidding and contract negotiations related to commissioned systems and assemblies are also reviewed to ensure they agree with the OPR.
Commissioning Planning and Kickoff Meetings. The CxP coordinates construction-phase planning and kickoff meetings. The planning meeting held with the contractor, owner, designer, and CxP focuses on reviewing requirements and establishing specific communication and reporting protocols. The commissioning plan is updated from this meeting. The kickoff meeting is held with additional construction team members, who generally include the mechanical, controls, electrical, and test and balancing contractors. At this meeting, the commissioning provider outlines the roles and responsibilities of each project team member, specifies procedures for documenting activities and resolving issues, and reviews the preliminary construction commissioning plan and schedule. Team members provide comments on the plan and schedule, and the CxP uses these suggestions to help finalize the commissioning plan and schedule.
Commissioning Plan Update. The planning and kickoff meetings usually result in an updated commissioning plan. Later, any project phasing or other schedule and scope-related issues (e.g., testing and training plans and schedules) are clarified in further updates.
Submittal Reviews.
Construction Submittals. The CxP reviews equipment and material submittals of commissioned systems and assemblies to obtain information needed to develop construction checklists, make meaningful observations of construction progress, and aid in developing comprehensive tests. This process also verifies that contractors are providing high-quality submittals that meet the construction document requirements, and that architects and engineers provide a quality review so construction-related performance issues are identified before construction progress makes them more difficult and expensive to address. Submittals could be reviewed concurrently by the design team to allow any discrepancies to be identified before formal approval, but the construction submittal review should also be compared to the architects’ and engineers’ reviews to verify that the architects and engineers are providing a thorough review of the submittals.
Controls Submittal and Integration Meeting. Before the contractor develops the controls submittal, the CxP coordinates a controls integration meeting to discuss and resolve methods for implementing performance specifications or strategies, interlocks between systems, priority of control between packaged controls and the central control system, the control system database, point names, graphic details and layout, access levels, etc.
Coordination Shop Drawings. The CxP may help the owner monitor the development and coordination of shop drawings to ensure synchronization between trades.
Early O&M Data. Information beyond typical construction submittals requested by the CxP includes installation and start-up procedures, operation and maintenance information, equipment performance data, and control drawings before formal O&M manual submittals. This information allows the CxP to become familiar with systems and assemblies to develop construction checklists, start-up plans, and test procedures.
Contract Modifications Review. Construction documentation issued during this phase, including requests for information, construction field directives, and change orders, should be reviewed by the CxP to identify issues that may affect commissioning and compliance with construction documents, BOD, or OPR.
Schedule Commissioning Field Activities. The CxP works with the discipline design engineers, contractors, and construction manager to coordinate the commissioning schedule and ensure that commissioning activities are integrated into the master construction schedule.
Construction and Commissioning Meetings. The CxP attends periodic planning and job-site meetings to stay informed on construction progress and to update parties involved in commissioning. During initial construction, the CxP may attend regular construction meetings and hold a line item on the agenda. Later, the CxP may convene entire meetings devoted to commissioning issues, with more frequent meetings as construction progresses. Attendees vary with the purpose of the meeting. Team members should be represented at meetings by parties with technical expertise who are authorized to make commitments and decisions for their respective organizations. The CxP should distribute minutes from these meetings.
Progress Reports. The CxP provides periodic progress reports to the owner and contractor with increasing frequency as construction progresses. These reports indicate current progress, next steps, and critical issues affecting progress and construction schedule.
Update Owner’s Project Requirement and Basis of Design. When contract negotiations and/or changes and clarifications made during construction alter or add to the OPR or BOD, these documents should be updated. Normally, the CxP updates the OPR and the designer updates the BOD. Final construction updates to these documents are made at the end of testing, typically a few months into occupancy.
Coordinate Owner’s Representatives Participation. The commissioning plan should describe participation of the owner’s representatives in work such as submittal review, construction checklist verification, construction observation, test procedure review and execution, and O&M manual review. The CxP normally coordinates this participation with the contractors.
Construction Observation. The CxP should make planned, systematic visits to the site to observe installation of systems and assemblies. The owner’s staff may assist in construction observation. The CxP should verify that the first few of any large-quantity items (e.g., variable-air-volume terminal units) are installed properly and used as a mock-up or standard to judge the rest of the installation. Any conditions not in compliance with the construction documents or BOD or that may affect system performance, commissioning, operation, or other project requirements should be documented. These observations normally focus on areas where observers have found problems before, or spot-check items on construction checklists. Less often, practitioners are tasked with validations or detailed inspections verifying that equipment or assemblies have been installed properly in every detail. Some practitioners make formal construction observation reports, whereas others merge findings into the regular issue logs and progress reports. Site visits should be used to verify completion of construction checklists.
The CxP normally witnesses many of the contractor’s start-up activities for major equipment to ensure checklists and start-up are documented properly and to gain additional feature and function information from installing technicians.
Record Documents. Contractors should be required to immediately update the record drawings when any deviations from the construction document occur. During the construction phase, the CxP should verify that the record documents are kept up to date by comparing the installation with the construction documents, and verify that any changes have been recorded on the record documents.
Construction Checklists and Start-up. At the beginning of construction, construction checklists are developed (usually by the CxP in cooperation with the discipline engineer, but sometimes by the contractor or equipment manufacturer) for most commissioned systems and equipment. They are attached to or integrated with manufacturer’s installation and start-up procedures. In most projects, contractors fill out the checklists during installation, during normal checkout of equipment and systems, and before and during system start-up, though some commissioning practitioners fill out the checklists themselves. The contractor fully documents start-up and initial checkout, including the construction checklists to ensure systems are ready for testing, and submits them to the CxP, who reviews the forms and spot-checks selected items in the field later in the project.
Some CxPs statistically sample items on checklists to verify proper completion (typically random or targeted sampling of 2 to 20%). If an inordinate fraction of the sampled items are deficient (typically more than 10%), the contractor is required to check and document all remaining items. The contractual documents need to contain details of the sampling and actions based on the results.
Commissioning Issues Management. The CxP keeps a record of all commissioning issues that require action by the design team, contractor, or owner. The issues should remain uniquely identified, be tied to equipment and systems, and prioritized relative to performance, cost, and schedule. Issues are tracked to resolution and completely documented. The CxP distributes the updated log to the owner, contractor, construction manager, and HVAC design engineer at construction and commissioning meetings. This log can also be placed on project web sites. If the CxP is hired through a contractor, the contractor’s commissioning manager or subconsultant may manage the contractor’s issues log. In that case, to minimize conflicts of interest, the CxP is often required to report all issues simultaneously to the contractor and to the owner.
Developing Test Procedures. Step-by-step test procedures and project-specific documentation formats are used for all commissioned equipment and assemblies. Manual tests evaluate systems with immediate results. Monitoring testing uses the building automation system or data loggers to record system parameters over time and analyze the data days or weeks later. Automated testing gathers or analyzes system performance data completely electronically, or with significant help from software. The system contractor should prepare and submit test procedures to the CxP, discipline engineer, and construction manager.
Test procedure writing begins immediately after the submittal, because test procedures need to be reviewed and approved before testing occurs, which is generally scheduled about three to six weeks after the submittal review. Test procedures may be based on specifications, applicable standards and codes, submittal data, O&M data, data shipped with the equipment, approved control drawings, and existing test procedures of similar equipment or components. Tests should cover all functions and modes.
Procedural documents clearly describe the test prerequisites, required test conditions, individual systematic test procedures, expected system response and acceptance criteria for each procedure, actual response or findings, and any pertinent discussion. Test procedures differ from testing requirements found in the specifications, which describe what modes and features are to be tested and verified and under what conditions. Test procedures describe the step-by-step method of how to test. Simple checklists may be appropriate for testing simple components, but dynamic testing of interacting components requires more detailed procedures and forms.
The responsible HVAC design engineer should organize the preparation of HVAC system testing, adjusting, and balancing (TAB) procedure together with the test and balancing professional and the commissioning provider, depending on their scopes of work. The CxP is responsible for verifying that the test procedures are written and appropriate for determining that equipment, assemblies, and systems function correctly. All parties should have input into the final test procedures to ensure that equipment, assemblies, systems, or people will not be endangered or warranties voided. Industry standard test procedures [e.g., ASHRAE, Air-Conditioning and Refrigeration Institute (ARI)] should be referenced whenever possible.
Testing and Verification.
Responsibilities and Management. Traditional air and water testing, adjusting, and balancing is often performed by the contractor or by an independent licensed professional employed by the contractor or by the owner. Building envelope, elevators, and building electrical system testing are generally excluded from HVAC commissioning, but may be included in whole-building commissioning. The CxP reviews the testing and verification plan along with the results, and may spot-check the results to verify the testing was completed. There is some movement in the industry to centralize coordination for quality assurance/quality control (QA/QC) functions under the commissioning team. Each project is unique, and different approaches can be warranted.
Critical issues include ensuring that
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Appropriate testing rigor is applied
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Technically qualified parties execute and document the testing
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Objectivity is maintained
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Testing is well documented
For systems not usually thoroughly tested by the contractor, such as specialty plumbing, the test procedure should be provided by the plumbing design engineer; for building envelope test procedures, by the architect or structural design engineer; and for interfaces between systems (security, communication, electrical, controls, HVAC, fire protection, emergency power), by the CxP with cooperation of related design engineers, along with contractors, who should provide interface drawings (Shieh 2009) and may write test procedures that go beyond HVAC tests. The CxP then directs, witnesses, and documents each test executed by the contractor after the contractors have ensured that the systems will pass these tests. The controls subcontractor usually executes the tests, although the CxP may test some equipment with or without the contractor present.
Testing that has traditionally been conducted by the contractor (e.g., fire alarm, fire protection, elevator, duct and pipe tests, emergency power, some electrical equipment) ideally should be centrally coordinated. This can be the responsibility of the contractor or of the CxP. The specifications should clearly establish testing and documentation requirements and define the responsible party. The level of confidence and objectivity can be increased by requiring experts in specific disciplines to witness tests, particularly in some electrical system and envelope assembly field testing. Increasing the required amount of field witnessing by the CxP also improves the confidence that commissioning was correctly performed.
Within a given discipline, there may be differing levels of autonomy. For example, in tests of electrical equipment (e.g., circuit breakers), the contractor may conduct and document the bolt-torque tests, and also be required to hire an independent certified testing agency to conduct other necessary tests that require more specialized expertise and test equipment.
The owner’s technical staff can assist in and benefit from participation in any of the above scenarios. The designer and owner’s project management staff may witness selected tests.
Verification Testing Scheduling. Verification testing should be performed after equipment and assemblies are complete and started up, construction checklists checked out and submitted, air and water balancing completed, and the contractors’ systems testing finished. The contractor is then ready to turn the system over to the owner. Most projects require a certificate of readiness from the contractor certifying that the system has been thoroughly checked out and verified to be completely functional. Ideally, manual testing occurs before substantial completion, but schedule slippage may require testing to occur after this milestone. Some short-term monitoring may be completed with manual testing, but sometimes is postponed until early occupancy. Opposite-season and other deferred testing should be conducted during seasonal changes or peak seasonal conditions.
Testing Scope. At a minimum, testing includes observing and documenting system operation and function during normal operation, through each of their sequences of operation, and all other modes of operation and conditions, including manual, bypass, emergency, standby, high and low load, and seasonal extremes, and comparing actual performance to that specified in the construction documents. Testing may also be conducted to verify performance criteria found in the BOD and OPR, including system optimization, though deficiencies in these areas are not normally the contractor’s responsibility.
Manual Testing Methods. Testing includes observing normal operation; changing set points, schedules, and timers; and exercising power disconnects, speed controls, overwriting sensor values, etc., to cause perturbations in the system. System response and results are recorded on test procedure forms, and any issues are documented. Small corrections are often made during testing. Less pressing corrections or issues with unknown solutions are investigated later, corrected, and retested.
Building automation systems (BAS), when present, can be the backbone for conducting much of the testing, collecting, and archiving data. Before using the BAS, critical sensors, actuators, and features should be verified as calibrated so the system readouts are reliable (although all sensors and actuators should have been calibrated by the contractor and documented on construction checklists). The results are viewed on the building automation system screen or at the equipment. Other tests may require hand-held instruments or visual verification (e.g., evaluating caulking and flashings on window installations).
Monitoring. Some testing requires monitoring (trending) system operation over time through the BAS or data loggers (when the BAS does not monitor desired points). Monitoring can be used to document that systems are performing properly during test conditions over the monitoring period. However, this is not a substitute for manual testing, which can cover a wide range of conditions. Monitoring provides a view of system interactions over the course of normal, start-up, shutdown, and weekend operation. Normally, the CxP analyzes monitored data and submits a report, with any concerns added to the issues log.
Automated Testing. Various semiautomated testing is conducted in permanent onboard equipment controllers. Currently, most truly automated testing focuses on identifying electrical faults in controller components and is used during vendor start-up and troubleshooting activities. Some use logic to identify parameters outside limits, which indicate component malfunctions such as hunting and calibration issues. Different types of automated testing intended to help commissioning are under development. Some are primarily tools to gather and display monitored data; others help the analyzer make diagnoses. Equipment manufacturers often integrate automated commissioning testing capabilities into onboard controllers on their equipment.
Training. Training should include, as appropriate, (1) the general purpose of the system; (2) use and management of the systems manual; (3) review of control drawings and schematics; (4) start-up, shutdown, seasonal changeover, and normal, unoccupied, and manual operation; (5) controls set-up and programming; (6) diagnostics, troubleshooting, and alarms; (7) interactions with other systems; (8) adjustments and optimizing methods for energy conservation; (9) relevant health and safety issues; (10) special maintenance and replacement sources; (11) tenant interaction issues; and (12) discussion of why specific features are environmentally sustainable. Occupants may also need orientation on certain systems, assemblies, and features in the building, particularly sustainable design features that can be easily circumvented.
The CxP helps the owner ensure that adequate training plans are used by the contractor and that training is completed according to the construction documents. (See the discussion of defining training requirements in the section on Commissioning During Design.) Some CxPs conduct testing with a sample of trainees to verify the efficacy of the training.
Most training should be accomplished during construction, before substantial completion. However, for complex systems (e.g., control systems), multiple training sessions should occur before and after substantial completion. Training for systems that will not come into operation until the next season may be delayed. A meaningful training program typically includes using the operation and maintenance components of the systems manual, which must be submitted by the contractor before training begins. Selected training materials can be video-recorded as desired by the owner.
Commissioning Record. The CxP compiles all commissioning documentation and project data, which are submitted and become part of the systems manual. The commissioning record contains the salient documentation of commissioning, including the commissioning final report, issues log, commissioning plan, progress reports, submittal and O&M manual reviews, training record, test schedules, construction checklists, start-up reports, tests, and trend log analysis, grouped by equipment.
Final Commissioning Report. The CxP should write (or review) and submit a final commissioning report detailing, for each piece of commissioned equipment or assembly, the adequacy of equipment or assemblies meeting contract documents. The following areas should be covered: (1) installation, including procedures used for testing equipment with respect to specifications; (2) functional performance and efficiency, including test results; (3) O&M manual documentation; and (4) operator training. Noncompliance items should be specifically listed. A brief description of the verification method used (manual testing, trend logs, data loggers, etc.) and observations and conclusions from the testing should be included. The CxP updates the final commissioning report after occupancy/operations-phase commissioning. The commissioning documents also should include, among other things,
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Certificates and warranties of system completion with a complete set of as-built drawings submitted from mechanical, electrical, piping, plumbing, control, and fire protection contractors
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Complete records of all deficiencies identified during start-up, testing, and adjustments submitted by every individual contractor or subcontractor
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Certified system testing and balancing report from the licensed TAB company, with verified major equipment models, capacities, and all tested performance records conforming to system design criteria
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If room pressurization is required, a complete room-to-room pressurization map in the TAB report
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If room cleanliness is required, a certified as-built room cleanliness report of testing during completion of construction and installation
Systems Manual Submittal. The CxP usually compiles the systems manual and provides it to the owner. At the end of construction, the designer, contractor, owner, and CxP provide elements of the systems manual generated during the construction phase. The systems manual should include commissioning test procedures, results of commissioning tests, issue logs and resolution, system schematics, O&M information, record drawings, construction checklists, walk-through records, start-up reports, and trend log analysis, grouped by equipment. The CxP normally reviews and approves systems manual submissions by the contractor and designer, similar to traditional O&M manual reviews. Electronic systems manuals, now developed occasionally, will likely become standard in the future. The owner should specify the format of the system manual in the contract scope, whether all in traditional paperwork, all electronic files, or in both formats.