EBOOK Refrigeration Commissioning Guide for Commercial and Industrial Systems EBOOK Hướng dẫn Vận hành Lạnh cho Hệ thống Thương mại và Công nghiệp (Ashrae 2014)

EBOOK Hướng dẫn Vận hành Lạnh cho Hệ thống Thương mại và Công nghiệp (Ashrae 2014) EBOOK Hướng dẫn Vận hành Lạnh cho Hệ thống Thương mại và Công nghiệp (Ashrae 2014) EBOOK Hướng dẫn Vận hành Lạnh cho Hệ thống Thương mại và Công nghiệp (Ashrae 2014) EBOOK Refrigeration Commissioning Guide for Commercial and Industrial Systems

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Commissioning Refrigeration Systems in

• Food Retail and Convenience Stores

• Small Retail Stores

• Food and Beverage Facilities

Industrial

Systems

Refrigeration Commissioning

for

Commercial

and

Guide

The Essential Guide for Commissioning Refrigeration Systems

The first of its kind, Refrigeration Commissioning Guide for Commercial and Industrial

Systems provides guidance to owners and managers of commercial and industrial

facilities that use refrigeration systems to help ensure that project requirements are

met and owners’ expectations are achieved For commercial facility owners and

managers, this means improved profitability through lower operating and service

costs as well as reduced product loss.

Because deficiencies in system design found at start-up are not easily resolved,

maintenance managers or operators may deal with unnecessary shortcomings

and expenses over the life of the facility Commissioning helps project teams avoid

these “surprises” by establishing a consistent, stepwise process that helps “get it

right the first time.” The commissioning process starts with the initial planning and

design and continues through construction, installation, start-up, and the first year

of system operation Commissioning also sets the stage for ongoing servicing and

maintenance of performance The result is refrigeration systems that are easier and

less expensive to install and maintain, with lower energy costs, minimized liabilities

from refrigeration system leaks, and reduced loss of refrigerated product due to

system failures or unreliable performance.

Using this Guide will help achieve cost-effective and cost-efficient refrigeration systems

for new projects, expansions, remodels, and existing systems that simply need a tune-up.

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Refrigeration Commissioning Guide

for Commercial and Industrial Systems

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Updates/errata for this publication will be posted on the ASHRAE website at www.ashrae.org/publicationupdates.

This publication was developed under ASHRAE’s Special Publication procedures and is not

a consensus document It was developed under the auspices of ASHRAE Special Project 137

and was supported with funding from U.S Department of Energy throughNational Renewable Energy Laboratory subcontract #AGN-1-11923

ASHRAE Staff Support

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Refrigeration Commissioning Guide

for Commercial and Industrial Systems

1791 Tullie Circle, NE Atlanta, GA 30329 www.ashrae.org

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ISBN 978-1-936504-53-4

1791 Tullie Circle, NE · Atlanta, GA 30329 · www.ashrae.org

Cover design by Laura Haass

ASHRAE is a registered trademark in the U.S Patent and Trademark Office, owned by the American Society of Heating, ating, and Air-Conditioning Engineers, Inc.

Refriger-ASHRAE has compiled this publication with care, but Refriger-ASHRAE has not investigated, and Refriger-ASHRAE expressly disclaims any duty

to investigate, any product, service, process, procedure, design, or the like that may be described herein The appearance of any technical data or editorial material in this publication does not constitute endorsement, warranty, or guaranty by ASHRAE of any product, service, process, procedure, design, or the like ASHRAE does not warrant that the information in the publication is free

of errors, and ASHRAE does not necessarily agree with any statement or opinion in this publication The entire risk of the use of any information in this publication is assumed by the user.

While supported by the U.S Department of Energy with the National Renewable Energy Laboratory, neither the United States government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal lia- bility or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed,

or represents that its use would not infringe privately owned rights Reference herein to any specific commercial product, process,

or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, mendation, or favoring by the United States government or any agency thereof The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States government or any agency thereof and shall not be used for advertising or product endorsement purposes.

recom-Except for rights reserved by the U.S Government, no part of this book may be reproduced without permission in writing from ASHRAE, except by a reviewer who may quote brief passages or reproduce illustrations in a review with appropriate credit; nor may any part of this book be reproduced, stored in a retrieval system, or transmitted in any way or by any means—electronic, pho- tocopying, recording, or other—without permission in writing from ASHRAE Requests for permission should be submitted at www.ashrae.org/permissions.

Library of Congress Cataloging-in-Publication Data

Refrigeration commissioning guide for commercial and industrial systems.

pages cm

Includes bibliographical references and index.

Summary: "Provides how-to guidance for commissioning custom-engineered refrigeration systems in commercial and industrial facilities to improve and supplement existing design, construction, and operational practices" Provided by publisher.

ISBN 978-1-936504-53-4 (softcover : alk paper)

1 Refrigeration and refrigerating machinery Industrial applications 2 Refrigerators Installation 3 Commercial Equipment and supplies Installation Planning I American Society of Heating, Refrigerating and Air-Conditioning Engineers TP492.R3785 2013

buildings 621.5'6 dc23

2013041539

ASHRAE S TAFF SPECIAL P UBLICATIONS Mark S Owen, Editor/Group Manager of Handbook and Special Publications

Cindy Sheffield Michaels, Managing Editor James Madison Walker, Associate Editor Roberta Hirschbuehler, Assistant Editor Sarah Boyle, Assistant Editor

Michshell Phillips, Editorial Coordinator

P UBLISHING S ERVICES David Soltis, Group Manager of Publishing Services and Electronic Communications

Jayne Jackson, Publication Traffic Administrator Tracy Becker, Graphics Specialist

P UBLISHER W Stephen Comstock

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Preface The Business Case for Commissioning: A Message to Owners vii

Acknowledgments ix

Chapter 1 Introduction The Need for Commissioning 2

Purpose and Scope 4

How to Use this Guide 7

Chapter 2 Commissioning during Planning and Design Introduction 9

Forming the Commissioning Team 13

Developing the Owner’s Project Requirements (OPR) 15

Managing the Issues Log 24

Developing the Commissioning Plan 25

Developing the Basis of Design (BoD) 28

Requirements for Construction Documents (CDs) 32

Deliverables and Acceptance 34

Chapter 3 Commissioning during Construction and Installation Introduction 37

Installation Planning and Scope of Work 41

Prefunctional Testing and Verification 45

Construction and Installation Details 50

Final Installation Commissioning and Review 55

Chapter 4 Commissioning during Start-Up and First-Year Operation Introduction 57

Commissioning Activities 59

Start-Up Report and Handoff to Owner 63

Activities in the First Year 64

First-Year Final Report and Acceptance 68

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Refrigeration Commissioning Guide for Commercial and Industrial Systems

Appendix A Roles and Responsibilities Matrix 73

Appendix B Example Commissioning Plan 77

Appendix C Example Acceptance Plan 85

Appendix D Technical Procedures 1 Verifying Control Functions 89

2 Verifying Refrigeration System Capacity 92

3 Evaluating Part-Load Operation 96

4 Checking Refrigerant Temperatures and Pressures and Evaluating Setpoints 98

5 Verifying Operation of Alarms 101

6 Evaluating Refrigerant Piping 104

7 Verifying Anti-Sweat Heater Control Operation 107

8 Verifying Defrost Adequacy and Defrost Control Operation 109

9 Minimizing Air Infiltration of Boxes and Cases 112

10 Evaluating the Use of Energy-Saving Features 113

Glossary 117

References 127

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Preface The Business Case for Commissioning:

is approximately 7% of commercial building energy use Nearly 70% of thiscommercial refrigeration use consists of supermarkets and other custom-designed refrigeration systems (DOE 2009)

Supermarkets are the largest example: a U.S Environmental ProtectionAgency (EPA) study estimates that supermarkets typically use approximately3,000,000 kWh of electricity per year, with 60% of that energy use attributed

to refrigeration (EPA 2007) Portland Energy Conservation, Inc (PECI) dicts that commissioning in existing grocery stores would result in 7% to 25%energy savings per year (PECI 2010) Based on these estimates, this commis-sioning guide, if widely adopted, would lead to substantial U.S nationalenergy savings

pre-Custom refrigeration systems are complex and individually designed foreach facility Deficiencies in the system design found at start-up are not easilyresolved and, as a result, maintenance managers or operators deal with unnec-essary shortcomings and expenses over the life of the facility The value ofcommissioning is to establish a consistent stepwise process that helps “get itright the first time,” resulting in refrigeration systems that “work right” andminimize maintenance and energy costs

Thousands of refrigeration systems are installed every year in facilitiesranging from convenience stores to large, sophisticated frozen food distribu-tion centers Properly commissioned systems reduce energy costs, are easier

to maintain, help minimize liabilities from refrigeration leaks, and reduce loss

of product due to system failures or unreliable performance

Commissioning of refrigeration systems is currently uncommon One son is the belief that commissioning results in added cost and time without

rea-Preface

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sufficient or measurable value Certainly, commissioning is an investment, but

it provides significant financial value in several ways First, systems operatemore reliably with lower maintenance cost and lower energy cost when com-missioning is applied as described in this Guide Second, incorporating com-missioning can reduce first cost through improved understanding of systemperformance and lead to better equipment design and installation methods.Using this Guide will help achieve cost-effective and cost-efficient refrig-eration systems for new projects, expansions, remodels, and existing systemsthat simply need a tune-up For commercial facility owners and managers, thismeans improved profitability through lower operating and service costs aswell as reduced product loss For industrial plants, this means improved “uptime” and improved labor productivity in addition to reduced operating cost.The commissioning process is holistic and considers life-cycle perfor-mance, including the long-term operating (utilities and servicing) costs of the

refrigeration system Commissioning is not another term for start-up The

commissioning process starts with the initial planning and design and ues through construction, installation, start-up, and the first year of systemoperation Commissioning also sets the stage for ongoing servicing and main-tenance of performance This Guide provides the process and methods to helpachieve these desired results: expected performance and reliability with thelowest life-cycle cost

contin-© 2013 ASHRAE (www.ashrae.org) For personal use only Additional reproduction, distribution, or transmission in either print or digital form is not permitted without ASHRAE's prior written permission.

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to bring order to the unorderly.

The primary authors were the members of ASHRAE Special ProjectCommittee 137 and provided the expertise and experience necessary todevelop the document They represented manufacturers, contractors, and endusers of refrigeration systems

The project would not have been possible without the financial support ofthe U.S Department of Energy (DOE) and National Renewable Energy Labo-ratory (NREL) as well as the invaluable support of ASHRAE In addition,DOE’s Better Buildings Alliance provided the project committee with thetechnical services of Rebecca Legett and Robert Zogg of Navigant Consult-ing, Inc I would also like to thank Paul Torcellini of NREL for his supportand help with the development of the document

I would also like to personally thank all the members of the project mittee for their diligence, creativity, persistence, and willingness to take time

com-to support the development and review of this Guide They worked extremelyhard to put together practical and fundamental information covering theaspects of commissioning applicable to a holistic approach Their expertiseand differing views greatly enriched this Guide The authors brought manydecades of experience, success, and failure to the text to achieve a significantmilestone for the refrigeration system owner and the refrigeration systemindustry I appreciate the patience of the committee members’ families duringthe development process, and I gratefully acknowledge the support of thecommittee members’ employers, including CTA; DC Engineering, PC;Edmonds Engineering Company; Hillphoenix; National Renewable EnergyLaboratory; PECI; Safeway, Inc.; Source Refrigeration and HVAC; Target

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Corporation; VaCom Technologies; Wal-Mart Stores, Inc; and Winn-DixieStores, Inc

Additional thanks go to the ASHRAE staff, including Lilas Pratt and BertEtheredge, whose direction and guidance were invaluable and whose organi-zational skills and dedication helped keep the project committee on track.Richard Royal

Chair, ASHRAE Special Project Committee 137

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as well providers of commissioning services.

Commissioning is a process for ensuring that a facility or system isdesigned and operated as intended Commissioning helps achieve larger goals

of sustainable design and operations, life-cycle cost-effectiveness, efficientuse of capital, minimizing overall maintenance costs and utility costs, longequipment life and reliability, and meeting performance expectations.ASHRAE addresses commissioning in two other publications: ASHRAE

Guideline 0, The Commissioning Process (2005), describes a general

commis-sioning process applicable to any facility or system and ASHRAE Guideline

1.1, HVAC&R Technical Requirements for the Commissioning Process

(2007), addresses how the commissioning process is applied to heating, lating, and air-conditioning (HVAC) systems, with some discussion of refrig-eration systems

venti-While Guideline 0 and Guideline 1.1 provide useful information, they donot readily address the needs of refrigeration systems Refrigerated facilitiesare both numerous and among the most energy-intense commercial buildings

Refrigeration Commissioning Guide for Commercial and Industrial Systems

builds on the concepts and process outlined in Guideline 0, providing specificmethods and approaches to achieve comprehensive commissioning of com-mercial and industrial refrigeration systems

Development of this Guide began after multiple discussions withinASHRAE concerning the value and need for such a publication and after con-sideration of many factors, such as the customized nature of refrigeration sys-tems as contrasted to packaged HVAC systems and the typical methods ofdesigning and contracting for refrigeration work These are two of the factorsthat have resulted in very limited commissioning of refrigeration systems incurrent practice The value of commissioning is clear to those designing andoperating for improved sustainability in refrigerated facilities To meet the

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apparent need and demonstrate the value of commissioning in the place, it became clear that refrigeration experts should define the needs, deter-mine the appropriate processes, and develop a guide specifically tailored forthe commissioning of refrigeration systems

market-THE NEED FOR

COMMISSIONING

Refrigeration systems for most commercial and industrial facilities arecustom-engineered for each application, with individual equipment selectedand matched to meet project needs and designer preferences In contrast, arooftop cooling unit or a packaged water chiller is factory built as a packagesubject to standards and certification as a combined system, with performanceand specifications fully described and catalogued While factory packages stillneed commissioning, the more customized nature of refrigeration is an impor-tant factor in defining how refrigeration commissioning will be accomplished.Refrigeration system designers choose the type of refrigerant, control valves,compressor technology, method of oil management, capacity control mea-sures, type of condensing (air or water cooled), and control system design andstrategies Supermarket store-planners determine which display cases will beused, what configuration will be laid out, and what merchandise will be in thecases Temperature, load, and evaporator layout can be completely uniquefrom project to project, requiring that compressors, condensers, evaporators,valves, and receivers be designed specifically for each project Various controlsystem providers and programmers contribute their products and services tothe completed system, which adds another layer of customization There arenot only numerous manufacturers of compressors, condensers, cases, coils,and controllers but also numerous owners and contractors with their uniquespecifications—resulting in the possibility for infinite variations

As with most construction projects, speed to market is critical Whilemany companies have well-established specifications and criteria, limiteddesign time can make design coordination difficult For example, to start pur-suing permits for a new facility, a preliminary refrigeration design may becompleted early in the process That design is then distributed for bidding andconstruction several months later When the equipment is received directlyfrom the providers, the contractor must integrate everything on site This pro-cess can result in the design’s intent being lost The commissioning processcan help to preserve that intent for manufacturers and programmers

Historically, the design and construction of commercial and industrialrefrigeration systems have not followed the approach where the architect isresponsible for all design engineers and a general contractor is responsible forall contractors Refrigeration design has typically been separate from thearchitect’s responsibility The entire refrigeration scope may be assumed by adesign-build contractor responsible for engineering the systems, providing theequipment, and performing the installation The owner may have multipledesign, equipment, and installation providers, all under separate contracts.Owners with multiple facilities may establish detailed criteria, design therefrigeration systems in house, rely on an original equipment manufacturer(OEM), or use a design consultant with refrigeration specialization Becausemuch of the commercial refrigeration business involves repetitive construc-tion (e.g., multifacility operations), refrigeration design often evolves fromone project to the next following a general criteria or relies on the experience

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ENERGY SAVINGS FROM COMMISSIONING

AS RELATED TO RETAIL SALES DOLLARS—A CASE STUDY

Background: A study of several recently opened stores owned by a large supermarket chain

revealed that each store had major shortcomings in the operation of its refrigeration and controlsystems The chain has a large development department that includes architects, engineers, proj-ect managers (PMs), construction managers, and others, so the store designs were based on awell-developed set of specifications and criteria drawings and should have all been operating thesame way Further investigation revealed that the contractors for the subject stores had not fol-lowed the plans and specifications

Problem: One specific store in California had been open for more than a year at the time of

the study The store had been designed to meet California Title 24 standards (CA 2013a, 2013b)and the store design had been evaluated by a leading engineering firm using energy modelingsoftware The modeling had shown that with all efficiency measures working properly the storeenergy use would be 2,800,000 kWh/year However, the actual energy use for this store during thefirst year of operation was 3,500,000 kWh/year

Lessons Learned: The Energy Management team developed and implemented a strategy to

retrocommission the store systems The result was a reduction in annual energy usage of 750,000kWh and annual cost savings of $90,000, bringing the system more in line with the expectationsgenerated by the model (see the figure)

Support for changes to address this issue at other stores and in future new constructionrequired attention from retail management But, the value of these savings is difficult to graspwhen the focus is on sales dollars Translating the savings into equivalent sales dollars shows thatthe average supermarket would have to sell approximately $4,500,000 in groceries (or about 10weeks’ worth of sales) in order to make up the dollar value of 750,000 kWh in energy savings.Additional savings would also result from reduced maintenance and/or a possible increase in salesfrom improved conditions in the store

The magnitude of the savings demonstrated the cost-effectiveness of a new construction missioning process that clearly defines expectations and verifies that equipment and controls areperforming according to expectations Subsequently, other stores in the chain also experiencedsavings ranging from 4% to 24% after similar retrocommissioning

com-Commissioning should start before design so that expectations are met at the start of tion rather than errors being discovered and having to be fixed only after excessive energy con-sumption is realized

opera-Energy Usage in Kilowatt-Hours as Designed, Before and After Commissioning

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of “what works” and ensures product temperature requirements are met.Design practice, equipment sizing, and performance expectations are highlydependent on the experience of designers and contractors Most refrigerationcomponents (unlike HVAC equipment) are not certified to a rating standard,and generally equipment catalogs do not reference a test standard Rules ofthumb and experience factors are inherent throughout the design, construc-tion, and operation of systems and are related to the built-up nature of nearlyall refrigeration systems and related control systems

Several retail chains have in recent years changed from reliance on dor- or contractor-provided engineering to employing a refrigeration designconsultant and incorporating refrigeration with the other mechanical engineer-ing responsibilities (e.g., HVAC, plumbing) This approach adds refrigeration

ven-to the traditional mechanical, electrical, plumbing (MEP) design consultantsand creates a mechanical, electrical, plumbing, and refrigeration (MEPR)team responsible to the owner and architect In addition, it has become moreprevalent for the general contractor to assume responsibility for the refrigera-tion subcontractor To address the fragmentation of the process, commission-ing seeks to provide a common thread with the purpose of creating high-performance refrigeration systems that meet specifications as well as mini-mize energy consumption while increasing reliability and maintainability

PURPOSE AND SCOPE

The purpose of this Guide is to outline a commissioning process forrefrigeration systems that can be readily adopted by a wide range of owners,designers, and contractors of commercial and industrial refrigeration systems

in the United States and globally The Guide is designed to start at projectconception and extend through the first year of operation Moreover, it alsoestablishes a basis for a continuous improvement process lasting throughoutthe life of the facility

This Guide is intended to improve and supplement existing design, struction, and operational practices Since most companies have successfullyrefined their practices to achieve on-time and on-budget projects, commis-sioning must be carefully considered and adopted such that the existingresponsibilities for design, supplier compliance, and contract completion arenot diminished Table 1-1 shows the people involved in commissioning a proj-ect and describes their roles or interests in the process

con-A key concept in the Guide is that the commissioning work is a process orfunction that entails multiple entities and individuals over the course of a proj-ect—commissioning is not simply the work of a single commissioning author-ity (CxA) The Guide is designed to be flexible and to acknowledge the variedmethods of designing and contracting refrigeration work across industry seg-ments and from company to company The Guide can be easily adopted in part

or in whole, without assuming one contracting method over another Users ofthe Guide will need to determine the elements that are appropriate to theirprojects, interests, and capabilities and define the responsibilities within avail-able company and project team resources

This Guide does not attempt to comprehensively address system design,detailed construction specifications, construction methods, or detailed routinestart-up procedures (e.g., oil and refrigerant charging methods), and it doesnot include safety topics

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Table 1-1 Potential Participants in the Commissioning Process

• Large company or chain where the owner is represented by an employee or a third-party agent

Tenant The tenant directly or indirectly pays for operating costs Some projects are built to suit the needs

for a particular tenant based on medium- or long-term arrangements.

Engineering

Team

Refrigeration design engineer(s), including the following:

• Consulting refrigeration engineer

• Engineer(s) for design-build contractor

• Refrigeration equipment supplier(s)

• Individual acting as Engineer of Record, as required Other engineers and disciplines, including the following:

• Thermal envelope designer, in the case of a refrigerated warehouse

• Control system designer, vendor, or contractor

• Electrical engineer, related to refrigeration equipment and controls integration with other systems

Contractors

Refrigeration contractor(s), including the following:

• One contractor providing and installing refrigeration equipment and controls

• A separate controls contractor

• A separate contractor for walk-ins or thermal envelope and doors

Commissioning

Service

Providers

Commissioning services may be provided by the following:

• Independent third-party commissioning consultants who manage and coordinate the overall commissioning process (see the sidebar “Best Practices for a Commissioning Authority: Independence, Perspective, and Understanding” in Chapter 2 of this Guide)

• A member of the design team

• The design-build refrigeration contractor

• Technical commissioning specialists who provide third-party testing and verification to implement the technical aspects of commissioning

• Chain supermarkets often have an operations division that prefers a standardized view of refrigeration focused on reliability, maintainability, and energy performance.

• An industrial project may require close coordination by plant operators, maintenance personnel, and production staff, particularly on an existing facility expansion.

• For a new facility, the on-site operations staff may be involved late in the process, only as they are hired or assigned to the location.

Energy and

Sustainability

Consultants

Various parties may be involved with energy efficiency and sustainability, including the following:

• Corporate departments measuring facility performance with metrics such as energy, water, and sustainability

• Energy efficiency consultant engaged by owner

• Utility and related program consultants for incentives and design assistance programs

• Labeling and certification program consultants (e.g., bEQ, LEED®, Green Globes, ENERGY STAR®)

Other

Projects with new or special equipment, systems, or technology may include an associated representative to assist with design integration and commissioning An Information Technology representative may be necessary to support data communications and management of information resources required to meet commissioning objectives.

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The Guide emphasizes refrigeration systems commonly used in cial and smaller industrial facilities (e.g., retail food stores, halocarbon sys-tems for warehouses, and small food facilities, etc.) While the commissioningprocesses outlined will also apply to commissioning of large industrial ammo-nia-based refrigeration systems and large built-up central compressor plants,specific technical procedures related to large industrial and ammonia systemsare not addressed in this Guide

commer-The phases of commissioning described in Refrigeration Commissioning

Guide for Commercial and Industrial Systems are, in order:

1 Planning and Design

2 Construction and Installation

3 Start-Up and First-Year OperationThis Guide is intended to be used within a variety of construction andcontracting arrangements, including the following:

• Design-build projects by refrigeration contractors

• Owner-designed projects installed by a refrigeration contractor

• Projects designed by the owner’s consultant and installed by a eration contractor

refrig-This Guide is expected to be used frequently by design-build contractors,who manage the commissioning process largely on the owner’s behalf and/orexecute the technical procedures While the benefit of an independent third-party perspective may not be achieved with this approach, this reflects thereality of the industry and how many commercial and industrial projects arecontracted as well as the fact that a great deal of the relevant expertise resideswith design-build contractors For this reason, the Guide is designed toaccommodate a “self-managed” method as well as apply to commissioningactivities performed by consultants and independent third parties Additionalperspective on third-party commissioning authorities is provided in the Chap-ter 2 sidebar “Best Practices for a Commissioning Authority: Independence,Perspective, and Understanding.”

This Guide is designed to address the characteristics of typical tion applications and systems, including the following:

refrigera-• Refrigeration systems must perform (maintain temperatures) at allhours of operation, in contrast to air-conditioning systems, whichmay be designed to meet temperatures a certain percentage of hours.The consequences of failing to maintain temperatures are thereforemore problematic in refrigeration systems than in air-conditioningsystems Thus, safety factors are a practical necessity for refrigera-tion systems, though the amount of safety factor realized by theinstalled equipment and systems is rarely quantitatively tested

• Refrigeration systems are custom built from components rather thanfactory-assembled packages As such, each system is unique andperformance is greatly affected by component interactions and con-trol methods Compressors and condensers are selected to meet theneeds of multiple loads and multiple application conditions, withcontrol valves and electronic control systems often selected andapplied by parties different than the provider of the major compo-nents

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• Retail chain stores and other large users commonly purchase ment directly from multiple vendors to increase competition andobtain the best-in-class product for each use Equipment may bespecified and purchased under blanket bidding/purchase agreements.

equip-• The owner (or engineer) often defines the manufacturer and the type

of operating controls energy management system (EMS) that will beincluded with the equipment from one or more OEMs and installed

by one or more contractors and then addressed by another controlscontractor to include HVAC and lighting This increases the integra-tion challenges and can contribute to uncertain responsibilities and alack of coordination between system design features, control systemcapability, and programming

As previously stated, this Guide is intended to address the needs of allcustom-designed refrigeration systems, including those for industrial applica-tions, retail food stores, and other commercial applications However, retailfood stores provided the largest source of examples concerning design, con-struction, and facility operations, and the examples vary by business size(including national chains, independent chains, and individually ownedstores), responsibility for design and design methods, contracting choices, andtype of maintenance operations Historically a large portion of refrigerationdesign in this sector has been provided by manufacturers and design-buildcontractors, along with a smaller portion of owner-designed and consultant-designed refrigeration and HVAC systems Plus, supermarkets are remodeledand expanded over the life of the facility, providing multiple opportunities torealize benefits from commissioning Using examples from this wide range ofindustry characteristics has resulted in a Guide that is expected to be adaptable

to other industrial and commercial refrigeration applications

Because commissioning is undertaken to achieve a project that meetsowner expectations, this Guide is designed on the assumption that the owner(or owner’s representative) will provide the assignment, directions, and over-all impetus for commissioning Commissioning will be most successful whenall project participants fully understand the commissioning process and takeinitiative and action in their areas of responsibility and expertise

There are two major aspects of the Guide: the commissioning process andthe technical procedures used in commissioning The process could be consid-ered the “business of commissioning” while the procedures are the “nuts andbolts” (i.e., how to commission)

In some cases, these constructs may overlap or not be perfectly separated.Users of the Guide may choose to draw the line between the process and tech-nical procedures in a manner that best suits their businesses and facilitydesigns and construction methods This Guide provides examples of only themost common technical procedures; individual Commissioning Plans shouldinclude the identification and development of project-specific technical proce-dures to ensure effective component- and system-level commissioning

HOW TO USE THIS GUIDE

Refrigeration Commissioning Guide for Commercial and Industrial tems traces the development of refrigeration systems from concept through

Sys-design, construction, and start-up Chapters 2, 3, and 4 cover the phases ofcommissioning: Planning and Design, Construction and Installation, and

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Start-Up and First-Year Operation Each chapter includes a flowchart withsteps outlined that users can follow to ensure that the end result will meet theexpectations of the owner as well as a roles and responsibilities table thatbreaks out the possible interested parties and their involvement in the commis-sioning process Sidebars are dispersed throughout the Guide to offer real-world examples to strengthen points and provide additional ideas and insights.The appendices provide resources for viewing the roles and responsibilities ofpeople involved in commissioning for all phases in one table (Appendix A),

an example Commissioning Plan (Appendix B), an example acceptance plan(Appendix C), and technical procedures that describe activities that may beconducted when commissioning refrigeration systems (Appendix D) Alsoincluded is a glossary of terms commonly used in refrigeration commission-ing practice

During the development of this Guide there was much discussion ing the need for consistent terminology within the refrigeration industry, andthe committee spent some time coming to a consensus on the terminology andacronyms used in this Guide Though there is no separate acronyms sectionincluded, the acronyms are indicated throughout the text when the terms areused and they are included in the glossary entries

regard-© 2013 ASHRAE (www.ashrae.org) For personal use only Additional reproduction, distribution, or transmission in either print or digital form is not permitted without ASHRAE's prior written permission.

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Commissioning during Planning and Design

INTRODUCTION

ensure that a project is designed to be “commissionable.” Starting the missioning process in this phase helps to establish a framework by whichcommissioning is embedded in the project from the beginning Specifically, itensures that the Owner’s Project Requirements (OPR) are the foundation ofthe project and that all subsequent phases of the project are based on this well-defined set of requirements This chapter describes the key documents devel-oped and activities undertaken in this phase to help ensure the project achievesthe goals defined in the OPR and to facilitate commissioning of the project

are the development or compilation of several key documents: the OPR, theBasis of Design (BoD), and construction documents (CDs) The Commission-ing Plan is developed and refined concurrent with development of these docu-

ments As explained in ASHRAE Guideline 0 (2005), the OPR describes what the owner’s requirements are for the project, the CDs show how the require-

ments are tangibly met, and the BoD ties the two together

Although these documents are developed during the Planning and DesignPhase, they must be revisited and revised as needed throughout the project.For example, if a requirement in the OPR cannot be met, the designer mustspecify why in the BoD, detail what was done instead, and seek approval fromthe owner to have the OPR revised In this regard, the OPR, BoD, and CDs,along with the Commissioning Plan, will be living documents throughout thelife of the project As the project progresses and new team members becomeinvolved in the project, these foundational documents must be made availableand presented with clear expectations so that everyone involved may be heldaccountable

As much as possible, the procedures, documents, guidelines, and forms to

be used during the construction, start-up, and first-year commissioning ties should be identified during the project design, realizing that some detailsmay change based on final design, equipment, and vendor selections An

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activi-Refrigeration Commissioning Guide for Commercial and Industrial Systems

important step during planning and design is to define the details and costsassociated with making the facility commissionable and to include informa-tion to define expectations and form a basis of comparison Examples of com-missionable items include pressure taps, flowmeters, specifications for datalogging and history capacity, etc These are often relatively minor costs whenincluded in the initial design but can be physically impossible or difficult from

a budget standpoint to add after a project is designed and under construction.Figure 2-1 details activities related to commissioning during the Planningand Design Phase and the order in which they should ideally occur Activitiesmay vary depending on the nature of the project

Defining the Scope

as the expectations that define success must be decided and clearly stated.The areas of design, specification, equipment, construction, and perfor-mance that affect commissioning or are affected by commissioning should bedecided on in order to define responsibility and involvement Table 2-1 pro-vides an example means of defining scope and involvement

Roles and Responsibilities

The roles and responsibilities of all entities directly or indirectly involved

in the commissioning process should be established as part of the sioning Plan Key roles in the commissioning process include, but are not lim-ited to, the following:

Commis-• Owner: The entity who owns the building and the project The owner

may assign a representative to perform commissioning tasks and beresponsible for core project parameters such as budget, schedule, andother project-specific restrictions and limitations—typically this per-son is the owner’s project manager (PM) The owner may set verydetailed and specific project requirements or, as in the case of adesign-build project, leave more of the means and methods up to themanufacturers and contractors

• Commissioning Authority (CxA): The entity managing the

commis-sioning process The CxA may be a subcontractor to the designer or

an independent contractor but should be independent of the designteam so as not to pose a conflict of interest

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Figure 2-1 Planning and Design Commissioning Flowchart

• Refrigeration Designer: The entity designing the refrigeration

sys-tem Depending on the applicable state and local codes, the ation designer may be a licensed, professional Engineer of Record.Depending on the owner or specific project, the refrigerationdesigner could be an employee of the owner, a consultant to theowner, or an employee of the contractor, such as in a design-buildproject

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refriger-Table 2-1 Example Scope Definition Document

Design Topic Example Details

Standard Documents

List of standard references and materials used for facility design (e.g., equipment lists, details, specifications) that are to be employed as part of the basis for overall project design.

Site-Specific Documents

List of site-specific development documents (e.g., surveys, planning reports) that are to be employed as part of the basis for overall project design.

Design and Contracting Summary

Definition of intended responsibility for design and construction, including as applicable design professionals, project managers (PMs), consultants, contractors, and how these will be selected at each phase of the project.

Design and Selection Criteria

Ambient conditions, codes and standards, criteria for system options (air vs water, refrigerants, direct vs indirect, etc.), guidelines for future capacity and functional flexibility, and tenant requirements.

Design Options Options to be developed for owner consideration and required

analysis (e.g., first cost, energy analysis, life-cycle calculations).

Operational Requirements

Temperature requirements in spaces and for equipment, operational hours, traffic peak and hourly assumptions, pull-down loads, and product definitions.

Economic Considerations

Facility life expectancy, incremental payback requirement, and budgets.

Load Calculations

Definition of responsibility for load calculations, tools to be used (e.g., peak design or modeling), and parameters required for subsequent commissioning.

System Design Standard product specifications, acceptable manufacturers and

product configurations.

HVAC/Mechanical Integration

Coordination of space conditions, methods of heat recovery, and requirements for performance measurement and commissioning.

Control System Integration

Network design, integration with other systems, standard vendors

or functional requirements, and functional definitions—where responsibilities, required level of detail, and sensor and data requirements must be adequately defined to support the commissioning process during system troubleshooting.

• Refrigeration Contractor/Installer: The entity hired to install the

refrigeration system or certain aspects thereof

• Refrigeration Original Equipment Manufacturer (OEM):

Manufac-turer of the refrigeration equipment, e.g., refrigerated cases, pressor racks, condensers, etc

com-• Other Contractors/Specialists: Other entities hired either directly by

the owner or as subcontractors to the designer who are responsiblefor certain aspects of the refrigeration system or its supporting ele-ments (e.g., a control system contractor)

• Building Service, Operations, and Maintenance Staff: People who

will occupy, operate, and support the refrigeration system and thebuilding itself throughout the life of the system

Table 2-2 shows an example of commissioning roles and responsibilitiesduring the Planning and Design Phase This table is an example for a project

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Table 2-2 Example of Roles and Responsibilities Matrix

in the Planning and Design Phase for an Owner-Specified Project

Role Responsibilities in the Planning and Design Phase

Owner or Owner’s Representative

• Provide OPR, site information, financial information, and product/equipment specifications.

• If desired, undertake cost/benefit analysis of saving features.

energy-• Provide direction on the extent of required commissioning

to be reflected in the OPR and Commissioning Plan.

• Review and approve BoD, Commissioning Plan, CDs, and sequence of operations (SoO) and accept deliverables.

• Identify which technical procedures must be performed as part of the commissioning process.

Commissioning Authority (CxA)

• Lead development of Commissioning Plan.

• Review OPR, BoD, CDs, SoO, and product/equipment specifications.

• Work with owner to identify technical procedures that are relevant to the project.

Refrigeration Designer (Engineer of Record)

• Develop the BoD, CDs, and SoO.

• Review product/equipment specifications and modify as needed.

• Provide input on cost/benefit analysis of energy-saving features, Commissioning Plan, and systems manual Refrigeration

Original Equipment Manufacturers (OEMs)

• Provide input on cost/benefit analysis of energy-saving features.

Control System Contractor

• Provide input on cost/benefit analysis of energy-saving features.

Facility Operations and Maintenance Staff • Provide input on site information, OPR, and BoD.

that is largely owner specified, with the owner providing many of the systemspecifications to the refrigeration designer and contractors (as opposed to adesign-build project, where the owner may provide minimal detail in therequirements) An example of a full roles and responsibilities matrix for allphases in one table is provided in Appendix A

FORMING THE COMMISSIONING

TEAM

The formation of the Commissioning Team is the first step in successfullyexecuting the commissioning process in the Planning and Design Phase It iscrucial for the owner to have appointed a CxA prior to the development of anyproject documents or requirements The CxA can also help the owner decidewhat other entities are required to make up a complete Commissioning Teamand also solicit the appropriate input from the team and the owner to generateproject documents

Since the activities of the CxA ideally extend from initial design throughthe first year of operation, the owner must contract for these services, whetherfrom one entity or several, separate from the construction contracts Themeans of contracting for CxA services will vary based on the practice fol-lowed by each owner, but a clear delineation of the CxA’s role, responsibili-ties, and authority is essential Moreover, the CxA’s activities must becoordinated with the commissioning-related work to be carried out by vendors

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and contractors as defined in the CDs As detailed in Annex L of ASHRAEGuideline 0 (2005), the CxA’s role must be considered and refined for eachproject to suit the owner’s business practices as well as project-specific neces-sities and constraints

In this Guide it is not assumed that there will be one CxA throughout theentire project While a single CxA entity is suggested as the best practicemodel, the industry requires time and experience for these skills and capabili-ties to develop and be offered by engineering practitioners and service provid-ers For some companies (e.g., multifacility operations), other methods may

be more consistent with their business practices

Contracting for CxA Services

The CxA’s role and responsibilities can be defined in a CxA specification

or in a project-specific request for proposal (RFP) describing the tasks theCxA will perform at each phase of the project Annex E of ASHRAE Guide-line 0 (2005) provides an example format that can be used to define responsi-bilities and request proposals for CxA services

Depending on the content of the project documents, the commissioningservices may be engaged using one of the following methods:

• Solicit proposals from prospective third-party CxAs

ROLE AND RESPONSIBILITY OF THE COMMISSIONING AUTHORITY

The text included in this sidebar is an excerpt from Annex L of ASHRAE Guideline 0 (2005).This annex provides an example of how to implement part of Guideline 0; it is not intended to be

a comprehensive representation or a best practice example

2 THE COMMISSIONING AUTHORITY (CxA) 2.1 The primary role of the CxA is to verify

achievement of the OPR throughout the project, fromPre-Design Phase through Occupancy and Opera-tions Phase The Owner should perform this role

2.2 When the Owner cannot perform the CxA

duties with qualified personnel, then the CxAshould have a separate professional services agree-ment with the Owner, as this avoids conflicts ofinterest and provides independence from the otherparties (the Owner’s project manager, designers ofrecord, construction managers, suppliers, and con-struction contractors) This professional servicesagreement defines the duties, rights, and responsi-bilities of the CxA for each phase of the project

This separate relationship allows the CxA to actindependently as director of Commissioning Pro-cess activities, to focus on achieving the OPR, and

to communicate directly with the Owner

2.3 The CxA is a group of personnel with

expertise and experience in the design, construction,and operations of the various systems and assem-

blies included in the project These personnel areled by an individual who has expertise and experi-ence in successfully implementing the Commission-ing Process

2.4 If the CxA is an employee, associate, or

partner of the same organization as the designer ofrecord or construction management firm, there is aconflict of interest While not a recommendedapproach, in these instances the CxA must have aseparate professional services agreement, be organi-zationally separate from the design team or con-struction management team, and define and managethe conflicts of interest to provide the Owner withthe independence required for the CommissioningProcess to be successful

2.5 The CxA does not perform testing; it directs

the process and directs the recording of the results.The CxA plans, schedules, and supervises Commis-sioning Process activities to verify achievement ofthe OPR The Contractor completes constructionchecklists, performs tests, and accomplishes otherCommissioning Process activities

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• Include commissioning responsibilities in the refrigeration tor’s scope of work.

contrac-• Usee the owner’s predetermined internal commissioning resources

• Use a prenegotiated third-party CxA

Specifying Commissioning

Activities

The construction contract documents should include the commissioningprocess activities the contractors are expected to perform during the construc-tion work and through their warranty period The contract specifications shoulddescribe the CxA’s role in each area of responsibly to avoid duplication ofeffort and cost and to maintain intended responsibilities Other sources, such asthe Commissioning Plan or the technical procedures, which become part of theCDs (described in more detail later in this chapter), may also be leveraged tohelp define and delineate the CxA and contractors’ scopes of work Additionalinformation on project bidding and contract placement is outlined in Chapter 3

DEVELOPING THE OWNER’S PROJECT REQUIREMENTS

con-BEST PRACTICES FOR A COMMISSIONING AUTHORITY:

INDEPENDENCE, PERSPECTIVE, AND UNDERSTANDING

Commissioning is best achieved when the commissioning authority (CxA) is an independentand impartial third-party entity with the technical skills and process experience to achieve thecommissioning objectives while creating value through coordination with all project participants.The greatest independence is achieved when the CxA is not involved in the project design,construction, or ongoing maintenance and operations This way, not only is the CxA able to bring

a fresh perspective to the project but the responsibility for managing the commissioning scope,content, and deadlines is more clearly defined

Being realistic about the “starting point.” At the present time, given both the very limited

use of commissioning for commercial and industrial refrigeration systems and the common tice of design-build construction for many commercial and industrial projects, it remains to beseen if and when qualified service providers (who are independent and unrelated to the project)will be available to provide refrigeration commissioning Most importantly, and the biggest chal-lenge, is that this is a highly technical undertaking Although the CxA is not the design engineer,the nature of refrigeration commissioning requires that the CxA be highly skilled and experienced

prac-in refrigeration system and control technologies prac-in order to work with designers, contractors, dors, and the maintenance team

ven-If the work of the CxA is performed by the project engineer, project contractor, or build contractor, the commissioning work should be performed by a separate department and staffwithin that person’s organization The CxA should not report to the person responsible for theproject design, the construction work, or the start-up team Achieving the desired independenceand impartiality will be largely dependent on how the firm is organized and manages their com-missioning business

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design-Refrigeration Commissioning Guide for Commercial and Industrial Systems

Owner’s Project Requirements document It includes information to help theproject team to properly plan, design, construct, operate, and maintain sys-tems and assemblies” (ASHRAE 2005, p 6)

The CxA facilitates the development of the OPR, and in order to fully develop an effective OPR, the Commissioning Team must be engaged inthe process—including the owner or owner’s representative, who is responsi-ble for core project parameters (budget, schedule, etc.) It is also recom-mended that the building operators, facility managers, store directors, andmaintenance personnel be involved in the OPR development Many timesthese individuals have valuable insight into the actual operation of the systemand facility and can help point out issues that can be addressed during design

success-by influencing the OPR For example, a supermarket store manager may knowfrom experience that the capacity of the typical ice flaker used may not pro-duce enough ice for the type of service fish cases that are planned to beinstalled in the store The OPR could then require the designer to address thisparticular capacity issue

Depending on the owner, a technical representative (often a mechanicalengineer or other technical individual employed by the owner) may be avail-able to represent the owner’s internal goals and directives For example, theowner’s project manager (PM) may know that certain refrigerants exhibit aglobal warming potential (GWP) and that it is the goal of their company toreduce their environmental impact by reducing the GWP of their refrigerationsystems; however, this person may not personally know what strategies toemploy to best deal with the issue The owner’s technical representative,therefore, would set requirements in the OPR such as what refrigerant should

be used, what type of system it should be used in, what charge minimizationstrategies should be used, what leak prevention efforts should be made, andhow the commissioning process will validate the company’s overall environ-mental strategy If an internal technical representative does not exist, theowner may rely on the CxA to help effectively communicate the requirements

in the OPR (Refer to the “Roles and Responsibilities” section of this chapterfor more detailed information on how the various team members can contrib-ute to the development of the OPR.)

Other examples of key items that should be contained in the OPR are cussed in the following sections Many of the requirements can be consideredproject specific; however, many of them reflect owner-specific requirementsthat may not change from project to project, such as the additional require-ment of quality for materials and construction It is important to leverage pre-established owner requirements that may already exist in the form of equip-ment and installation specifications, owner-developed design and installationguides, or even CD criteria sets Many owners use these types of documents as

dis-a pldis-atform to dis-administer their interndis-al godis-als dis-and directives in dis-a consistentmanner, so simply referencing these documents in the OPR can be an effectiveway of including the requirements they contain

Key Items to Include in the OPR

Project Budget and Schedule

Sufficient detail should be included to document the project budget andschedule so that the entire project team knows the limitations Depending on

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the type of system to be installed, sufficient budget and time must be allocated

to allow for proper design, installation, start-up, and commissioning Sincemany refrigeration systems are custom built for the application, input from thedesigner and/or manufacturer may be necessary to accurately adjust the bud-get and schedule on a project-by-project basis

CONDENSER STACK ATTACK—A CASE STUDY

Background: Many grocery stores are built fairly close to residential areas and have to

address noise issues in order to be good neighbors Some cities have noise ordinances with cific requirements to keep equipment noise below the established threshold during evening/night-time hours Various design solutions may be employed to accommodate these noise abatementrequirements

spe-Problem: One design resolution to accommodate noise issues is the “stack attack” option

shown in the figure In this design, condenser fan stacks are installed on top of the condensingequipment Unfortunately, this particular design solution creates service issues and increases costsassociated with changing out the condenser fan motors It is unlikely that these issues will be real-ized until problems arise associated with condenser fan motor failures (e.g., high head pressures).When that occurs, it is likely that a crane will be required to safely lift the stacks so the condenserfan motors can be replaced and to reset the stacks onto the condenser when the work is completed.The need for a crane greatly increases the both the costs and time required for what should be rou-tine maintenance In this particular case study, the cost was increased by $5000 for local cranefees and the replacement took all day

identification of alternate design options to meet site noise abatement requirements that do notcreate costly service situations This design solution created a very expensive service challengeand an unsafe maintenance process In addition, once installation is complete, retrofitting thistype of situation can be expensive, and the process of reviewing information and evaluating sup-porting systems may impact the operation of the store

Photograph courtesy of NREL; credit John de la Rosa

Why are Those Stacks on the Condenser Fans?

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Commissioning Process Scope and Budget

Identifying the equipment, components, and systems to be commissionedand assigning a budget to carry out the commissioning tasks is essential.Depending on the size of the scope and budget, commissioning could befocused on just the control and operation of the equipment in the compressorroom, or it could also include condensers, evaporators, piping systems,pumps, peripheral controls, etc

Technical Procedures

All technical procedures that will be conducted for commissioning, asspecified in the Commissioning Plan (see the section “Developing the Com-missioning Plan” in this chapter), must be reviewed, and the CxA must ensurethat any information or data necessary for fulfilling a given technical proce-dure is included in the OPR

Submittal Requirements

Specify how the submittals will be coordinated, reviewed, and approvedand who will be responsible for these functions

Project Documentation Requirements

With input from the owner’s technical representative and the CxA, specifywhat documentation will be required for effective commissioning, who will beresponsible for providing it, and in what format it should be provided Depend-ing on the nature of the facility and the owner’s preference, the documentationmay include only refrigeration-related content or may address all aspects of thefacility Additionally, the owner should specify a method for retaining, storing,and/or displaying these documents in order to preserve them for the life of thesystem and to allow for updating as changes, additions, and improvements aremade to the documents or the facility itself (see Figure 2-2)

Photographs courtesy of NREL; credit John de la Rosa

Figure 2-2 Examples of Displayed Project Documentation

As a best practice, documentation retention should include, at a minimum,the following:

• Owner’s Project Requirements

• Basis of Design documents

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• Start-up records

• Commissioning report

• Systems manual (including operations and maintenance manuals)

• Training materials and optimization guidance

• Ongoing operating dataOngoing operating data may include the following:

• Refrigerant leak and recharge records

• Oil usage log (additions and removal history)

• Maintenance and emergency repair records

• Equipment logs (periodic manually prepared forms and/or computerprintouts)

Training Requirements for

Owner’s Personnel

The CxA and all parties who will provide training information should beinvolved in the development of training requirements and expectations Inputfrom those who will be responsible for using the training materials is alsoimportant

The expectation for sufficient training should be documented and nicated directly with the expected trainer or included within any applicableRFP Typically, system manufacturers will offer some sort of training forequipment that is considered unique or a new technology For example, refrig-erated display cases may require training on how to properly load the cases oroperate various features of the cases

commu-In addition, the training process and timing must be defined While ple entities may be involved with aspects of training, particularly on a largeproject or with new technologies, training coordination is necessary to ensureinformation is fully and effectively made available on a timely basis to theindividuals who need it Chapter 4 discusses how to review the training activ-ity during the Start-Up and First-Year Operation Phase

multi-Developing training requirements and implementing training for a projectinvolves the following actions:

• Identifying who requires training, when, and how frequently

• Defining who will provide training (e.g., vendors, engineers, training

or subject specialists, etc.)

• Establishing a training calendar for the project

• Identifying additional requirements for new technologies or specialinstallation conditions

• Identifying certifications required of operating staff or contractors

• Specifying safety-related requirements per company policy and ernmental agencies (e.g., local codes, Occupational Safety andHealth Administration, Environmental Protection Agency, etc.)

gov-• Providing safety training before start-up or change activities

• Providing safety training after completion, with hands-on action

inter-• Providing individual safety qualification on standard operatingprocedure (SOP), when applicable

• Providing training on remote access, control interface, and other datasystems

• Defining the responsibility for maintaining and administering ing references and training support

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ongo-Refrigeration Commissioning Guide for Commercial and Industrial Systems

Warranty Requirements

The terms of warranty for all systems and components to be sioned should be collected and included in the OPR for reference so that allwarranties may be preserved throughout the project Chapter 4 discusses how

commis-to review warranty requirements during start-up and through the first year ofoperation

Benchmarking Requirements

Beyond requiring that benchmarking must be part of the CommissioningPlan, the owner must specify what the benchmark targets will be, when thebenchmarking should happen, what the means of measurement are, and whatthe benchmark deliverable needs to look like The CxA should help developthese requirements to ensure that the commissioning work performed and thegenerated deliverable is as meaningful as possible For example, if weatherdata and facility conditions are not recorded when the system benchmark isrecorded, then the information cannot be used to its full potential Chapter 4discusses the documentation of performance benchmarks during first-yearoperation

Operation and Maintenance Requirements

Include expectations regarding the yearly maintenance budget and theexpected capability of the service contractor To realistically set these require-ments, collaboration with the service technician may be required

Load and Sizing Calculations

Designate the responsibility for performing load calculations and definethe operational parameters, derating or safety factors, and related system-siz-ing criteria Adherence to these design parameters and responsibilities should

be maintained during the development of the design Once the systembecomes operational, commissioning feedback should be provided regardingthe efficacy of the load and sizing calculations and methods

Environmental Sustainability and

Energy-Efficiency

Goals

Environmental goals can be expressed in the OPR in many ways, such asdictating what type of refrigerant to use, what the total refrigerant chargeshould be, how much energy the refrigeration system should use, or even whatthe system’s total equivalent warming impact (TEWI) or life-cycle climateperformance (LCCP) number should be As previously discussed, depending

on the level of internal technical representation available to the owner, the cifics of how to achieve these environmental goals may or may not beincluded in the OPR The requirement should still be firm, but it may leavemore of the means and methods up to the designer to achieve the end goal.Any requirements for obtaining building ratings or certifications (e.g,bEQ, LEED®, Green Globes, GreenChill, or ENERGY STAR®) should bespecified The targeted level of awarded certification should also beexpressed

spe-The energy goals of a project are directly related to the environmentalgoals and, similarly, there are many different ways to address the require-ments Some of the ways to set the energy requirements are

• requiring equipment to meet a specified payback period,

• referencing an industry energy baseline and requiring that the systemeither meet this baseline or achieve a certain percentage deviationfrom it, or

• requiring that the equipment meet a certain preset performance ification that can be verified through kilowatt-hour monitoring

spec-© 2013 ASHRAE (www.ashrae.org) For personal use only Additional reproduction, distribution, or transmission in either print or digital form is not permitted without ASHRAE's prior written permission.

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System Type The system type is requirement that cannot necessarily be set until after

the environmental and energy goals have been identified Sometimes, theenvironmental and energy goals will require the use of a type of system thatthe owner has no experience with While some owners may give the designerthe authority to simply pick a system type and manufacturer that fits theirdesign, many owners have a selection of approved manufacturers and systemtypes that they will require to be used

Community Requirements

The owner should understand the surrounding community and setrequirements to make sure that the team and the installed systems do not neg-atively impact that community Sometimes community engagement will benecessary to successfully complete a project For example, projects where vis-ible and/or audible rooftop equipment will be installed may require approvalfrom surrounding neighbors With the use of some “natural” refrigerants, the

Emergency Planning and Community Right-to-Know Act of 1986 (EPCRA)

may come into play and require that certain steps are taken to properly engagethe community

Refrigerant Charge

Calculations and Refrigerant Management

The OPR should clearly define the responsibility for calculation of erant charge(s), confirmation of actual system charge, and identification ofany leaks or adjustments needed to accurately define the proper operating sys-tem charge In order to improve future designs, also define the responsibilityfor investigating variances from the expected charge and report reasons.Define the management systems for tracking refrigerant use from start-upthrough the first year of operation, including continuity between constructionand maintenance record keeping

refrig-Adaptability The OPR should specify whether the installed system should be able to

adapt and expand to meet the predicted future needs of the facility and, if itshould, to what degree it should be able to do so

List baseline acoustical requirements and express additional requirementsfor special situations Examples of special situations include mechanical roomwalls that are shared with other tenants or neighbors that are in close proxim-ity to rooftop condensers

Vibration Requirements

List vibrational requirements, especially when nontypical roof systems ormezzanines are used to support condensers and compressors Also includeseismic requirements for projects that are located in special seismic zones

Constructability Requirements

In addition to recording any known constructability restrictions specific tothe project site, the owner may choose to require that a constructability review

be performed by the installing contractor once the CD permit set is issued Theproject schedule and construction schedule should be reviewed to make surethat the pieces can come together in the right order One example of this isensuring that roof curbing is set before condensers are craned to the roof so thatthe racks can be ready to run when the evaporators are needed to refrigerate

Maintainability and Accessibility Requirements

Set requirements for equipment accessibility to allow for proper and cient maintenance This is a requirement that will demand some architecturalcoordination to ensure that spaces adequately allow for proper clearances and

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effi-Refrigeration Commissioning Guide for Commercial and Industrial Systems

pathways Proper storage and trash handling should be addressed to reducegarbage and clutter around equipment

Communication Requirements

Include any remote monitoring requirements for the purposes of nance, trend logging, or performance comparisons

mainte-Systems Communication and Controller Requirements

Aside from specifying which controls manufacturer should be used, ify what communications should take place between integrated systems.Beyond this, the expectation should be set for the designer and the controllerprogrammer to closely coordinate throughout the project to ensure that thedesign intent is executed in the final control of the system (refer to the sidebar

spec-“Sensors for Condenser Control—A Case Study” for more information) Toaccomplish this coordination, the owner may require that the designerdevelop a sequence of operations (SoO) for the system and include it in theBoD and CDs

New Technology Requirements

Include any requirements to use the latest advancements in technologies.Current examples of the latest advancements include electronic expansionvalves (EEVs), electronic evaporator pressure regulators (EEPRs), digital com-pressor unloading, variable-speed electrically commutated (EC) motors, etc

SENSORS FOR CONDENSER CONTROL—A CASE STUDY

Background: A supermarket remodel and expansion was designed to use closed-loop

evapo-rative fluid coolers for heat rejection connected to water-cooled condensers at the refrigerationracks (see the figure) The two fluid coolers used 30 hp (22.5 kW) motors equipped with variable-speed motors and were to provide floating head pressure using a variable setpoint (i.e., wet-bulb-following) control strategy The chain, which more commonly used air-cooled condensers, haddeveloped this system design to save energy in hot, dry climates as well as to reduce refrigerantcharge

Problem: During a store visit on a cool, dry day, well after the store opened, the fluid cooler

fans were observed at minimum speed, concurrent with near design condensing temperatures.Investigation determined that the sensors for the wet-bulb-following strategy were missing andwere not shown on the drawings In addition, the controller was set for a high, fixed head pres-sure The design concept (and significant capital investment) was undone by this control defi-ciency By simple rule of thumb (1.5% to 2% energy per degree Fahrenheit of condensingtemperature), the loss in efficiency during average weather conditions would exceed 20% Theimportance and lost savings are as follows:

Before After Savings

Annual refrigeration, kWh 900,000 700,000 200,000Annual refrigeration operating cost $120,000 $100,000 $20,000Cost to correct controls $2500Payback 2 monthsThe necessary control changes were made at low cost, although with some effort, since it wasfound that the controller model had certain logic limitations, which may explain why the neededsensor had been deleted in the first place

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Lesson Learned: The sequence of operations (SoO) typically employed by this chain to

define control operation either was not completed or was not coordinated with the mechanicaldesign incorporating a fluid cooler system From an economic standpoint, the extra capitalinvested in the fluid cooler system was wasted without the appropriate sensor and control logic.The missing sensors and/or control system limitations would have been more evident, taken onhigher importance, and likely been addressed if a CxA had been

• involved in the Planning and Design Phase,

• looking forward to the expected goals at project start-up,

• armed with the design intent as defined in the BoD, and

• aware of the financial implications.

The lack of a key sensor or fundamental control strategy from the drawings would be ent to the CxA during construction and start-up only if the overarching objectives were under-stood—in this case that would include floating head pressure, which was standard practice for thisowner Had this project included commissioning, the desired action by the CxA would have been

appar-to identify the technical solution, budget, and responsibility for changes appar-to achieve the designintent; to ensure that the changes were completed and verified; and to provide feedback to addressthe same deficiency in other stores of the same vintage

This example shows the type of responsibility and authority required to deal with one lar issue While the economics shown are striking, often the impacts are not at all as obvious dur-ing construction The CxA frequently needs to understand the economic ramifications in order tojustify the effort required to identify and enact changes that require research, design, and work bymultiple trades

particu-Schematic of Fluid Cooler/Condenser Loop

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Applicable Code,

Standard, and Guideline Requirements

In addition to the state and federal codes that must be followed, the OPRshould make it clear whether there are any additional applicable standards orguidelines that should be followed for the project

System Redundancy Requirements

Specify the level of redundancy that should be accounted for in thedesign Redundancy requirements could be applied to many different aspects

of design, such as compressor or pump redundancy—or even to the load Forexample, the owner could require that the frozen temperature evaporators besplit across multiple different compressors (or compressor racks) so that if one

is lost the frozen product may be restocked to other frozen cases or freezerboxes

Compressor Staging Requirements

Along with the redundancy and safety factor requirements, the OPRshould express the requirements for proper equipment staging to react toreduced loads and increased system capacities due to low-ambient conditions.This requirement can be set in various degrees of detail, leaving more or less

of the means and methods for achieving proper staging to the designer

Power Failure Requirements

Since refrigeration systems often protect thousands of dollars of productthat will be lost if the refrigeration system loses power, the OPR shouldinclude any requirements for how the system should react to power failure

MANAGING THE

ISSUES LOG

The issues log contains detailed descriptions of any design, installation,and performance issues that are at variance with the OPR Issues are identifiedand tracked as they are encountered and resolved through all phases of com-missioning It is particularly important to establish responsibility for main-taining the log at the beginning of the project and, if the entity responsiblechanges over the course of the project, have an effective means for transfer-ring responsibility to maintain continuity

The issues log is a living document that tracks issues from their initialidentification to their closure Once an issue is identified, it should berecorded in the issues log along with an initial plan for resolving it As stepsare taken toward resolution, each step should be documented Finally, once anissue is closed (whether or not it is resolved as planned) the outcome should

be noted and preserved in the issues log for future reference

For each item in the issues log, information to be documented mayinclude the following:

• Issue number: a unique issue identifier for location in a database

• Date the issue was identified

• Who identified the issue

• Description of the issue

• Initial recommendations for issue resolution

• Who is responsible for resolving the issue (may be more than oneentity)

• Date entity responsible for resolution was notified of the issue

• Steps taken toward resolution and dates these steps occurred

• Status of issue (open or closed)

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The format for the log (e.g., electronic or paper, list or table) should also

be established at the outset of the project Examples of two different templatesfor formatting an issues log are shown in Table 2-3 and Figure 2-3

Table 2-3 is a spreadsheet where each issue corresponds to a line on thesheet This example may be best suited for an online database or computerfile Advantages of this format are that multiple issues can be viewed side byside and the issues can easily be sorted based on various characteristics

In Figure 2-3, each issue is described on a one-page worksheet Thisexample may be best suited for a binder on site, with several blank sheets forissues that come up during the course of the project Advantages of this for-mat are that all details on a particular issue are in one place and easy to trackand the sheets can easily be annotated in the field as steps are taken to resolvethe issues

commission-if a formal OPR is not developed, or is not defined as such, the ing Plan has the purpose of ensuring that the intended operational perfor-mance of the system over the life of the facility is realized Because of thevariance in design and configuration from one project to another, the Commis-sioning Plan for the refrigeration system will most likely be unique for eachproject, even for repetitive chain store projects Nonetheless, the Commission-ing Plan should be developed in the Planning and Design Phase of the project

Commission-to help ensure that the system is commissionable as it is designed and built

As described in the Introduction, commissioning is a process involvingmultiple parties beginning with the initial project design and extending

Table 2-3 Example Issues Log—Electronic Version

# Issue

Issue Description

Date Identified

Contractor Responsible

Date Contractor Notified Action Taken

Issue Resolution (Open / Closed)

Date Resolved

1

2

Etc.

past

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Issue #:

Project Name:

Project ID:

Most probable certain benefit to owner:

Most probable benefit to design team:

Most probable benefit to construction team:

Noneconomic benefits to the building:

Figure 2-3 Example Issues Log—Paper Version

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start-up In addition to the primary design team, there are many others to sider in developing the Commissioning Plan Selected contractors, vendors,manufacturers, and service providers need to understand what commissioning

con-is and what it means to the project Their roles and expected involvement must

be clearly defined

The Commissioning Plan spans a time period including

• design,

• construction and installation,

• start-up and opening, and

• the first year of operation

The Commissioning Plan includes

dur-• Procedures for timing of equipment selection, which vary from pany to company

com-• The choice of design-bid vs design-build contracting, which affectsresponsibilities, budgets, and timing

• The addition of team members during the project process

• Design changes and option selections that occur over the course ofthe project, which often impact facility performance

The following sections should be considered in developing the sioning Plan Appendix B of this Guide includes an example CommissioningPlan and illustrates additional details for these sections

Commis-1 Overview—Summarize the purpose and use of the Commissioning

Plan

2 Roles and Responsibilities—Define responsibilities for management

and implementation of commissioning at each step of the process.The Commissioning Plan should include a list of team membersinvolved in the project and their contact information Examplesinclude consultants, contractors, and staff

Commissioning is not a replacement for system start-up sibilities or installation quality assurance, which should be defined inconstruction contracts and vendor agreements The roles and respon-sibilities for commissioning work should be clearly distinguishedfrom the construction activities

respon-3 Communications—Define the frequency and timing of

communica-tion as well as who has responsibility for disseminating informacommunica-tionand reports throughout the commissioning process

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4 Schedule—Develop a schedule of key milestones and activities As

the project progresses, the schedule should be updated with actualdates, events, and resolutions

5 Commissioning Processes—Detail the site-specific activities

devel-oped to achieve commissioning goals and define the following foreach phase of the project:

• Planning and Design

• Construction and Installation

• Start-Up and First-Year Operation

An important aspect of the Commissioning Plan is defining the designand decision-making responsibilities, information needs, and sequence ofevents necessary to accomplish the technical aspects of commissioning Spe-cifically, the Commissioning Plan should detail how performance expecta-tions are to be defined and measured and should outline key equipmentspecifications that are easily addressed at the right time but can be physicallyimpossible or too expensive to address once equipment is ordered or construc-tion is complete Examples of key equipment specifications include pressuretaps, flowmeters, specifications for data logging and history capacity, etc

a result of the OPR being revised The expectation then is for the CxA to usethe most up-to-date BoD to effectively commission the CDs and ensure thatthe OPR is being satisfied by the design This is one of the most importanttasks for the CxA during the Planning and Design Phase since it allows issuesand concerns to surface as the design is being developed The technical proce-dures being performed as part of commissioning should also be reviewed, and

DOE REFRIGERATED CASE STANDARDS

The recent work of the U.S Department of Energy (DOE) on 10 CFR 431, Part III, assignedclassification to commercial refrigeration display cases This work established standardization forthe calculation of case energy by class of case, which supports the designer with a higher defini-tion of system load/balance

Tables summarizing these standards are available on the DOE Energy Efficiency & able Energy (EERE) Building Technologies Office website under Appliance & Equipment Stan-dards for Commercial Refrigeration Equipment: www1.eere.energy.gov/buildings/appliance_standards/product.aspx/productid/52

Renew-© 2013 ASHRAE (www.ashrae.org) For personal use only Additional reproduction, distribution, or transmission in either print or digital form is not permitted without ASHRAE's prior written permission.

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any information that must be included in the BoD to successfully performeach procedure should be added to the BoD.

In summary, the BoD should address all of the major requirementsincluded in the OPR To best illustrate how the BoD accomplishes this task,some basic examples are given in Table 2-4, in the order that they would likely

COMPRESSOR PERFORMANCE: RATED VS APPLIED CONDITIONS AND IMPLICATIONS FOR DESIGN AND COMMISSIONING

The current design practice and difference between nominal rated compressor capacity (CC)and applied conditions results in a large difference between apparent and actual capacity, particu-larly for commercial refrigeration applications The capacity on paper is not the real capacity,which has implications for the commissioning process and procedures, since commissioning fun-damentally is addressing expected vs actual performance This situation provides an example ofthe necessary interaction and relationship between design practice and commissioning

In terms of achieving the desired cooling capacity and temperatures, compressors are themost important component in a refrigeration system Since temperatures in most applicationsmust be met 100% of the time, systems are naturally designed from a conservative point ofview—the consequences of not meeting temperatures are expensive to resolve and very unattract-ive for all involved This is in contrast to commercial HVAC systems wherein, for cost-effective-

ness, good design practice expects temperatures will exceed design conditions for a few hours out

of the year A consequence of this difference is that HVAC load calculations and system capacityare honed by “being on the edge,” in contrast to refrigeration applications where a system with

“unmet cooling hours” is completely unacceptable

Low-temperature compressors will most often be much more heavily loaded than temperature compressors In fact, it isn’t unusual for all low-temperature compressors to be run-ning when only half of the medium-temperature compressors are on And, on paper, medium-tem-perature systems often have less safety factor While this may be due to greater load diversity onmedium-temperature systems or differences in how walk-in loads are calculated, the main issue isusually a striking difference in how the compressors are rated and applied

medium-Commercial refrigeration compressors are rated based on ANSI/AHRI Standard 540 (2004),which include a fixed 65°F (18°C) return gas temperature (RGT) entering the compressor, regard-less of the saturated suction temperature (SST) This means that the rated capacity for a compres-sor operating at –20°F (–29°C) assumes all heat required to superheat the suction gas to 65°F(18°C) is productive refrigeration, whereas the actual productive suction gas temperature is likely

no greater than 0°F (–18°C), the temperature leaving the display case or freezer box The ancy between rated capacity and the actual cooling capacity is often 20% or more This appears to

discrep-be addressed by compressor manufacturers’ software, which provides for variable suction gastemperature However, the software adjustments are approximations (generally a simple ratio ofsuction gas density), not based on additional compressor testing at more common conditions

This historical discrepancy in compressor ratings is inherent to the process of design practice,load calculations, and general experience and expertise in the industry Safety factors and capacityadjustments have evolved from experience and will continue to improve In this example, the need

is for improved compressor rating conditions and testing along with a better understanding ofactual loads

The figures help illustrate these concepts by describing productive and nonproductive superheat

by defining points on a pressure-enthalpy diagram and a physical refrigeration system schematic

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