1、43.1CHAPTER 43HVAC COMMISSIONINGCONSIDERATIONS 42.1Commissioning Objective 43.2Management and Responsibilities . 43.2COMMISSIONING PROCESS 43.4Predesign-Phase Commissioning 43.5Design-Phase Commissioning . 43.5Construction-Phase Commissioning 43.8Occupancy- and Operations-Phase Commissioning . 43.11
2、Life and Property Safety Check 43.11COMMISSIONING COSTS 43.12Design-Phase Costs (Including Predesign andDesign) . 43.12Construction- and Occupancy/Operations-PhaseCosts . 43.12Existing Buildings 43.13Certification . 43.13OMMISSIONING implements a quality-oriented process forCachieving, verifying, an
3、d documenting that the performance offacilities, systems, and assemblies meets defined objectives and cri-teria. The defined objectives and criteria are often referred to as theowners project requirements (OPR). The commissioning pro-cess uses the owners project requirements as the reference to dete
4、r-mine acceptance of the design and construction. Commissioningincludes verifying and documenting that the project operational andmaintenance documentation and training of operation and mainte-nance personnel occur. The result should be fully functional sys-tems that can be properly operated and mai
5、ntained throughout thelife of the building.This chapter gives an overview of the general commissioningprocess as covered in ASHRAE Guideline 0-2013, developed for theNational Institute of Building Sciences total building commission-ing program, as well as the best practices for applying the processf
6、rom ASHRAE Guideline 1.1-2007. The minimum acceptable pro-cess for commissioning is detailed in ASHRAE Standard 202-2013.This chapter provides more narrative discussion on some issues thanthese two guidelines and the standard.Recommissioning applies commissioning to a project that hasbeen previously
7、 delivered using the commissioning process. This maybe a scheduled recommissioning developed as part of ongoing com-missioning, or it may be triggered by use change, operational prob-lems, or other needs. Existing building commissioning (often calledretrocommissioning) applies commissioning to an ex
8、isting facilitythat may or may not have been previously commissioned. It consistsof systematically investigating, analyzing, and adjusting operations ofexisting building equipment, systems, and assemblies, as well astraining and documentation for operators to ensure that required per-formance (inclu
9、ding energy, comfort, and IAQ) is achieved. Buildingsrequire maintenance and tuning to prevent performance degradation.Existing building commissioning should be performed as part ofongoing efforts to maintain a comfortable and efficient environmentwithin the building. It has broad application to vir
10、tually every buildingtype with excellent cost/benefit results and payback ratios. Existingbuilding commissioning starts with development of the owners cur-rent facility requirements, reviewing the existing design, and testingof the existing systems. Any major retrofits required follow the pro-cess f
11、or new building commissioning as defined in this chapter.1. CONSIDERATIONSApplicabilityThe commissioning process described here applies to new con-struction, major renovations, and all systems and assemblies.Although this chapter focuses on HVAC systems, commissioningcan be applied to the building a
12、s a total system, which includesstructural elements, building envelope, life safety features, electricalsystems, communication systems, plumbing, irrigation, controls,and HVAC systems (ASHRAE Guideline 0). Based on owners pref-erence and project contract scope, total commissioning can includeindustr
13、ial process and process equipment, systems, piping, instru-mentation, electrical, and related control, or these topics may betreated as an independent phase of project commissioning.Systems to be commissioned vary with the systems and assembliesused, building size, project type, and objectives. Owne
14、rs and commis-sioning providers often focus on systems and assemblies under thecommissioning umbrella that have (1) historically not performed wellat turnover (e.g., outside air economizers and variable-speed drives),(2) are mission critical (e.g., air cleanliness in a cleanroom, emer-gency power in
15、 a hospital), (3) will be costly to fix during occupancyif they fail (e.g., chilled-water piping, window flashing assemblies),or (4) present a life-safety risk if they fail (e.g., fire alarm, smoke con-trol, moisture penetration). Recommendations in this chapter shouldbe appropriately modified for e
16、ach project. Although commissioningmay begin at any time during the project life cycle, owners obtain thehighest benefits when commissioning begins at the conceptual or pre-design phase.BackgroundEquipment, components, systems, and assemblies have becomemore complex. More specialization has occurred
17、 in the disciplinesand trades, with increased interactions between all elements. Thisincreased specialization and interaction requires increased integra-tion between disciplines and specialized systems by the deliveryteam. Owners often use low-bid policies, and scopes of design pro-fessionals are of
18、ten narrowed. The result has been buildings thatdo not meet owner expectations and often do not work as intendedbecause of programming, design, and construction deficiencies.Commissioning is a value-added service that helps overcome theseinfrastructure inadequacies and fundamentally improve the perf
19、or-mance of building systems and living conditions for occupants.BenefitsThe primary benefits of commissioning include improvements inall of the following areas:Predesign and design- Owners develop better understanding of what they want and needthrough clear, documented OPR- Designers understand bet
20、ter what owner is requesting- Designers reduce their risk with better communication and inputfrom owner- Owners understand better what designers are proposing througha clear, documented basis of design (BOD)The preparation of this chapter is assigned to TC 7.9, Building Commis-sioning.43.2 2015 ASHR
21、AE HandbookHVAC Applications- Experts review and improve commissioning documents- Resolves many potential issues more cost effectively beforeconstruction phase- Verifies planned systems can be commissioned and tested, andare within owners ability to maintain- Improves specifications and drawings, re
22、sulting in improvedcoordination between all groups- Includes thorough training requirements in the construction doc-umentsConstruction (including system and assembly performance)- Increases accountability in submittal process, leading to higher-quality installation- Provides tools to help contractor
23、s perform installations that meetthe project requirements (e.g., construction checklists)- Provides performance accountability through constructionobservation, issue management, and testing- Documents verification of system and assembly performance- Verifies training completion- Includes formal func
24、tional testing at completionOccupancy and operations (including maintenance)- Improves performance (IAQ, comfort, energy) from start ofoccupation - Reduces amount of troubleshooting- Has fewer contractor call backs- Ensures thorough documentation in operation and mainte-nance (O and (2) verifyand do
25、cument compliance with these criteria throughout design,construction, acceptance, and initial operation phases.Specific goals for commissioning includeProviding documentation and tools to improve quality of deliver-ables (e.g., forms, tracking software, performance calculationtools)Verifying and doc
26、umenting that systems and assemblies performaccording to OPR by end of construction with building occu-pancyProviding a uniform and effective process for delivery of con-struction projectsUsing quality-based sampling techniques to detect systemic prob-lemsVerifying proper coordination among all cont
27、ractors, subcontrac-tors, vendors, and manufacturers of all furnished equipment andassemblies in the completed systemsVerifying that adequate and accurate system and assembly docu-mentation is provided to ownerVerifying that operation and maintenance personnel and occu-pants are properly trained1.2
28、MANAGEMENT AND RESPONSIBILITIESManagement StrategiesIn each project, a qualified party should be designated as thecommissioning authority (CxA).Predesign and Design. Commissioning during predesign anddesign is most often managed by an independent CxA who is not partHVAC Commissioning 43.3of the form
29、al designer-of-record team. An independent, objectiveview is critical. The CxA normally provides input to the owner anddesigners but does not have ultimate authority over design decisions.The CxA should also coordinate, conduct, or approve activities suchas assisting in development of the OPR, condu
30、cting statistical sam-pling reviews, and developing commissioning specifications and testprocedures. The CxA may also review plan designs.Construction. During construction, because of the variety ofplayers, construction management scenarios, and the owners objec-tives, numerous methods are used to m
31、anage the commissioningprocess. To maintain objectivity, the CxA should be independent. Ifthe contractor or designer hires the CxA, the potential conflict ofinterest must be carefully managed. The two primary methods tomanage commissioning during construction are commissioning-authority-managed and
32、contractor-managed.In the commissioning-authority-managed approach, theCxA performs many of the planning and technical tasks, such asdeveloping the commissioning plan and test procedures anddirecting, witnessing, and documenting execution of tests, per-formed by either the contractor or the CxA.In t
33、he contractor-managed approach, the contractor maydevelop the commissioning plan, write test procedures, and directand document testing, with the CxA reviewing and approving theplan, witnessing selected tests, and reviewing completed testreports. The CxA should report to the owner on the adequacy of
34、 acontractor-managed commissioning plan. The contractor mayassign staff, a subcontractor, or a subconsultant to manage and coor-dinate commissioning responsibilities. This approach gives the con-tractor more responsibility. Some view this method as lessobjective, but others consider it more integrat
35、ed into the buildingdelivery process than the CxA-managed approach.Some project plans use both management approaches, particu-larly when a substantial amount of electrical equipment is beingtested. HVAC and controls follow the commissioning-authority-managed approach, and electrical system commissio
36、ning followsthe contractor-managed approach, but the entire process is still over-seen by the single CxA.Team MembersEffective building commissioning requires a team effort. The sizeand makeup of the team depends on the size and complexity of theproject and the owners desire for quality assurance. T
37、eam membersinclude the owner, occupants, design professionals, constructionmanager, general contractor, subcontractors, suppliers, equipmentmanufacturers, and the CxA.The level of effort of team members changes during the differentproject phases. For example, during design, the designer is a keyplay
38、er in the commissioning process, whereas the contractor maynot have been selected. During construction, the general contrac-tors and installing subcontractors roles increase.The scope of work of the CxA, design professionals, and con-tractors should be clearly and completely identified in their con-
39、tracts. Without this, change orders, incomplete or missed tasks, andotherwise dysfunctional commissioning may result.Roles and ResponsibilitiesThe commissioning teams responsibilities are to conduct com-missioning activities in a logical, sequential, and efficient mannerusing consistent protocols an
40、d forms, centralized documentation,clear and regular communications and consultations with all neces-sary parties, frequently updated timelines and schedules, and appro-priate technical expertise. The following sections summarize theresponsibilities of each party. Additional detail is found in the C
41、om-missioning Process section.Commissioning Authority. Specific responsibilities vary withthe management scenario and the CxAs specific scope of services.Ideally, the same party or firm acts as CxA through all projectphases. The CxA organizes and leads the commissioning teamthroughout the project.Pr
42、edesign and Design Phase. During predesign, the CxA devel-ops the predesign and design-phase commissioning plan andensures the OPR is developed.During design, the CxA develops detailed commissioning activ-ities. The core CxA responsibilities areReviewing designers BOD, plans, and specifications, ens
43、uringthey meet the OPRDeveloping initial construction-phase commissioning planEnsuring that the commissioning, training, and documentationrequirements for all contractors and suppliers are reflected in con-struction contract documentsConstruction. During construction, the CxA is in charge of thecomm
44、issioning process and makes the final recommendations to theowner about functional performance of commissioned building sys-tems and assemblies. The CxA directs commissioning activities, andis an independent and objective advocate for the owner. The corecommissioning activities during construction i
45、nvolveReviewing selected construction submittals to verify confor-mance with OPR, with updates in commissioning plan as neededObserving selected installations, start-up, and functional perfor-mance tests, including documenting any conditions that requirecorrectionCo-organizing with the discipline de
46、sign engineer, and planning,developing, reviewing, and observing testingCodeveloping or assisting with systems manualReviewing O relative humid-ity; lighting power density; glazing fraction; U-value and shadingcoefficient; roof, wall, and ceiling R-values; ventilation and infil-tration rates; etc.)F
47、ire and life safety issuesSummary of primary HVAC load calculations and the methodsusedDevelopment and Use. The BOD is written by the designer andincreases in details as design progresses. The CxA may need toobtain this explanatory information from the designer. An updatedBOD with increased detail s
48、hould be submitted with each newdesign submission. Each submission is reviewed by the owner andCxA as part of design reviews.Develop Commissioning Plan for Construction and Occu-pancy/Operations Phases. The commissioning plan (Cx plan) is adocument that outlines the organization, schedule, allocatio
49、n ofresources, and documentation requirements of the commissioningprocess. This is an overall plan, developed during the predesign,design, and construction phases, that provides the structure, schedule,and coordination planning for commissioning. The Cx plan includesspecifications detailing the scope, objectives, and process of commis-sioning during the construction and occupancy/operations phases ofthe project. It must specify the scope of work, roles, responsibilities,and requirements of the construction contractor. For the constructionand occupancy/operations phases, it de
copyright@ 2008-2019 麦多课文库(www.mydoc123.com)网站版权所有
备案/许可证编号:苏ICP备17064731号-1