RH HANDBOOK OF AIR CONDITIONING AND REFRIGERATION TX Shan K Wang Second Edition McGraw-Hill New York San Francisco Washington, D.C Auckland Bogotá Caracas Lisbon London Madrid Mexico City Milan Montreal New Delhi San Juan Singapore Sydney Tokyo Toronto SH ST LG 39445 Wang (MCGHP) FM FIRST PASS pg iv LMM 6/29/2K Library of Congress Cataloging-in-Publication Data Wang, Shan K (Shan Kuo) Handbook of air conditioning and refrigeration / Shan K Wang — 2nd ed p cm Includes index ISBN 0-07-068167-8 Air conditioning Refrigeration and refrigerating machinery I Title TH7687.W27 697.93 — dc21 2000 00-060576 McGraw-Hi l l Copyright © 2001, 1993 by The McGraw-Hill Companies, Inc All rights reserved Printed in the United States of America Except as permitted under the United States Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a data base or retrieval system, without the prior written permission of the publisher DOC/DOC ISBN 0-07-068167-8 The sponsoring editor for this book was Linda Ludewig, the editing supervisor was David E Fogarty, and the production supervisor was Pamela A Pelton It was set in Times Roman by Progressive Information Technologies, Inc Printed and bound by R R Donnelley & Sons Company This book was printed on acid-free paper McGraw-Hill books are available at special quantity discounts to use as premiums and sales promotions, or for use in corporate training programs For more information, please write to the Director of Special Sales, Professional Publishing, McGraw-Hill, Two Penn Plaza, New York, NY 10121-2298 Or contact your local bookstore Information contained in this work has been obtained by The McGraw-Hill Companies, Inc (“McGraw-Hill”) from sources believed to be reliable However, neither McGraw-Hill nor its authors guarantee the accuracy or completeness of any information published herein, and neither McGraw-Hill nor its authors shall be responsible for any errors, omissions, or damages arising out of use of this information This work is published with the understanding that McGraw-Hill and its authors are supplying information but are not attempting to render engineering or other professional services If such services are required, the assistance of an appropriate professional should be sought 39445 Wang (MCGHP) FM REV PAGES rg 08/15/00 pg v This book is dedicated to my dear wife Joyce for her encouragement, understanding, and contributions, and to my daughter Helen and my sons Roger and David 39445 Wang (MCGHP) index REV PGS rg 08/15/00 pg I.29 RH TX ABOUT THE AUTHOR Shan K Wang received his B.S in mechanical engineering from Southwest Associated University in China in 1946 Two years later, he completed his M.S degree in mechanical engineering at Harvard Graduate School of Engineering In 1949, he obtained his M.S in textile technology from the Massachusetts Institute of Technology From 1950 to 1974, Wang worked in the field of air conditioning and refrigeration in China He was the first Technical Deputy Director of the Research Institute of Air Conditioning in Beijing from 1963 to 1966 and from 1973 to 1974 He helped to design space diffusion for the air conditioning system in the Capital and Worker’s Indoor Stadium He also designed many HVAC&R systems for industrial and commercial buildings Wang published two air conditioning books and many papers in the 1950s and 1960s He is one of the pioneers of air conditioning in China Wang joined Hong Kong Polytechnic as senior lecturer in 1975 He established the air conditioning and refrigeration laboratories and established courses in air conditioning and refrigeration at Hong Kong Polytechnic Since 1975, he has been a consultant to Associated Consultant Engineers and led the design of the HVAC&R systems for Queen Elizabeth Indoor Stadium, Aberdeen Market Complex, Koshan Road Recreation Center, and South Sea Textile Mills in Hong Kong From 1983 to 1987, Wang Published Principles of Refrigeration Engineering and Air Conditioning as the teaching and learning package, and presented several papers at ASHRAE meetings The First Edition of the Handbook of Air Conditioning and Refrigeration was published in 1993 Wang has been a member of ASHRAE since 1976 He has been a governor of the ASHRAE Hong Kong Chapter-At-Large since the Chapter was established in 1984 Wang retired from Hong Kong Polytechnic in June 1987 and immigrated to the United States in October 1987 Since then, he has joined the ASHRAE Southern California Chapter and devoted most of his time to writing SH ST LG I.29 DF 39445 Wang (MCGHP) FM REV PAGES rg 08/15/00 pg xi RH TX PREFACE TO SECOND EDITION Air conditioning, or HVAC&R, is an active, rapidly developing technology It is closely related to the living standard of the people and to the outdoor environment, such as through ozone depletion and global warming Currently, air conditioning consumes about one-sixth of the annual national energy use in the United States At the beginning of a new millennium, in addition to the publication of ASHRAE Standard 90.1-1999 and ASHRAE Standard 62-1999, often called the Energy standard and Indoor Air Quality standard, the second edition of Handbook of Air Conditioning and Refrigeration is intended to summarize the following advances, developments, and valuable experience in HVAC&R technology as they pertain to the design and effective, energy-efficient operation of HVAC&R systems: First, to solve the primary problems that exist in HVAC&R, improve indoor air quality through minimum ventilation control by means of CO2-based demand-controlled or mixed plenum controlled ventilation, toxic gas adsorption and chemisorption, medium- and high-efficiency filtration, and damp surface prevention along conditioned air passages ANSI/ASHRAE Standard 52.2-1999 uses 16 minimum efficiency reporting values (MERVs) to select air filters based on particle-size composite efficiency Energy conservation is a key factor in mitigating the global warming effect Electric deregulation and the use of real-time pricing instead of the time-of-use rate structure in the United States have a significant impact on the energy cost ANSI/ASHRAE Standard 90.1-1999 has accumulated valuable HVAC&R energy-efficient experiences since the publication of Standard 90.1-1989 and during the discussions of the two public reviews For buildings of one or two stories when the outdoor wind speed is normal or less than normal, the space or building pressurization depends mainly on the air balance of the HVAC&R system and on the leakiness of the building A proper space pressurization helps to provide a desirable indoor environment Second, there is a need for a well-designed and -maintained microprocessor-based energy management and control system for medium-size or large projects with generic controls in graphical display, monitoring, trending, totalization, scheduling, alarming, and numerous specific functional controls to perform HVAC&R operations in air, water, heating, and refrigeration systems HVAC&R operations must be controlled because the load and outside weather vary The sequence of operations comprises basic HVAC&R operations and controls In the second edition, the sequence of operations of zone temperature control of a single-zone VAV system, a VAV reheat system, a dual-duct VAV system, a fan-powered VAV system, and a four-pipe fan-coil system is analyzed Also the sequence of operations of a plant-building loop water system control, the discharge air temperature control, and duct static pressure control in an air-handling unit are discussed Third, new and updated advanced technology improvements include • Artificial intelligence, such as fuzzy logic, artificial neural networks, and expert systems, is widely used in microprocessor-based controllers • BACnet is an open protocol in control that enables system components from different vendors to be connected to a single control system to maximize efficiency at lowest cost • Computational fluid dynamics is becoming an important simulation technology in airflow, space diffusion, clean rooms, and heat-transfer developments xi DF 39445 RH TX xii Wang (MCGHP) FM FIRST PASS pg xii LMM 6/29/2K PREFACE • Scroll compressors are gradually replacing reciprocating compressors in packaged units and chillers because of their higher efficiency and simple construction • Ice storage systems with cold air distribution shift the electric power demand from on-peak hours to off-peak hours and thus significantly reduce the energy cost • Desiccant-based air conditioning systems replace part of the refrigeration by using evaporative cooling or other systems in supermarkets, medical operation suites, and ice rinks • Fault detection and diagnostics determine the reason for defects and failures and recommend a means to solve the problem It is a key device in HVAC&R operation and maintenance Fourth, air conditioning is designed and operated as a system In the second edition, HVAC&R systems are classified in three levels At the air conditioning system level, systems are classified as individual, evaporative, space, packaged, desiccant-based, thermal storage, clean-room, and central systems At the subsystem level, systems are classified as air, water, heating, refrigeration, and control systems At the main component level, components such as fans, coils, compressors, boilers, evaporators, and condensers are further divided and studied Each air conditioning system has its own system characteristics However, each air conditioning system, subsystem, and main component can be clearly distinguished from the others, so one can thus easily, properly, and more precisely select a require system Fifth, computer-aided design and drafting (CADD) links the engineering design through calculations and the graphics to drafting CADD provides the ability to develop and compare the alternative design schemes quickly and the capability to redesign or to match the changes during construction promptly A savings of 40 percent of design time has been claimed Current CADD for HVAC&R can be divided into two categories: engineering design, including calculations, and graphical model drafting Engineering design includes load calculations, energy use estimates, equipment selection, equipment schedules, and specifications Computer-aided drafting includes software to develop duct and pipework layouts and to produce details of refrigeration plant, heating plant, and fan room with accessories ACKNOWLEDGMENTS The author wishes to express his sincere thanks to McGraw-Hill editors Linda R Ludewig and David Fogarty, Professor Emeritus W F Stoecker, Steve Chen, and Professor Yongquan Zhang for their valuable guidance and kind assistance Thanks also to ASHRAE, EIA, and many others for the use of their published materials The author also wishes to thank Philip Yu and Dr Sam C M Hui for their help in preparing the manuscript, especially to Philip for his assistance in calculating the cooling load of Example 6.2 by using load calculation software TRACE 600 Shan K Wang SH ST LG DF 39445 Wang (MCGHP) FM REV PAGES rg 08/15/00 pg xiii RH PREFACE TO THE FIRST EDITION TX Air conditioning, or more specifically, heating, ventilating, air ventilating, air conditioning, and refrigeration (HVAC&R), was first systematically developed by Dr Willis H Carrier in the early 1900s Because it is closely connected with the comfort and health of the people, air conditioning became one of the most significant factors in national energy consumption Most commercial buildings in the United States were air conditioned after World War II In 1973, the energy crisis stimulated the development of variable-air-volume systems, energy management, and other HVAC&R technology In the 1980s, the introduction of microprocessorbased direct-digital control systems raised the technology of air conditioning and refrigeration to a higher level Today, the standards of a successful and cost-effective new or retrofit HVAC&R projects include maintaining a healthy and comfortable indoor environment with adequate outdoor ventilation air and acceptable indoor air quality with an energy index lower than that required by the federal and local codes, often using off-air conditioning schemes to reduce energy costs The purpose of this book is to provide a useful, practical, and updated technical reference for the design, selection, and operation of air conditioning and refrigeration systems It is intended to summarize the valuable experience, calculations, and design guidelines from current technical papers, engineering manuals, standards, ASHRAE handbooks, and other publications in air conditioning and refrigeration It is also intended to emphasize a systemwide approach, especially system operating characteristics at design load and part load It provides a technical background for the proper selection and operation of optimum systems, subsystems, and equipment This handbook is a logical combination of practice and theory, system and control, and experience and updated new technologies Of the 32 chapters in this handbook, the first 30 were written by the author, and the last two were written by Walter P Bishop, P E., president of Walter P Bishop, Consulting Engineer, P C., who has been an HVAC&R consulting engineer since 1948 Walter also provided many insightful comments for the other 30 chapters Another contributor, Herbert P Becker, P E., reviewed Chaps through ACKNOWLEDGMENTS The authors wishes to express his sincere thanks to McGraw-Hill Senior Editor Robert Hauserman, G M Eisensberg, Robert O Parmley, and Robert A Parsons for their valuable guidance and kind assistance Thanks also to ASHRAE, EIA, SMACNA, The Trane Company, Carrier Corporation, Honeywell, Johnson Controls, and many others for the use of their published materials The author also wishes to thank Leslie Kwok, Colin Chan, and Susanna Chang, who assisted in the preparation of the manuscript Shan K Wang SH ST LG xiii DF 39445 Wang (MCGHP) FM REV PAGES rg 08/15/00 pg vii RH TX CONTENTS Preface to Second Edition xi Preface to First Edition xiii Chapter Introduction 1.1 Chapter Psychrometrics 2.1 Chapter Heat and Moisture Transfer through Building Envelope 3.1 Chapter Indoor and Outdoor Design Conditions 4.1 Chapter Energy Management and Control Systems 5.1 Chapter Load Calculations 6.1 Chapter Water Systems 7.1 Chapter Heating Systems, Furnaces, and Boilers 8.1 Chapter Refrigerants, Refrigeration Cycles, and Refrigeration Systems 9.1 Chapter 10 Refrigeration Systems: Components 10.1 Chapter 11 Refrigeration Systems: Reciprocating, Rotary, Scroll, and Screw 11.1 vii SH ST LG DF 39445 Wang (MCGHP) FM FIRST PASS pg viii LMM 6/29/2K RH viii TX Chapter 12 Heat Pumps, Heat Recovery, Gas Cooling, and Cogeneration Systems 12.1 Chapter 13 Refrigeration Systems: Centrifugal 13.1 Chapter 14 Refrigeration Systems: Absorption 14.1 Chapter 15 Air Systems: Components — Fans, Coils, Filters, and Humidifiers 15.1 Chapter 16 Air Systems: Equipment — Air-Handling Units and Packaged Units 16.1 Chapter 17 Air Systems: Air Duct Design 17.1 Chapter 18 Air Systems: Space Air Diffusion 18.1 Chapter 19 Sound Control 19.1 Chapter 20 Air Systems: Basics and Constant-Volume Systems 20.1 Chapter 21 Air Systems: Variable-Air-Volume Systems 21.1 Chapter 22 Air Systems: VAV Systems — Fan Combination, System Pressure, and Smoke Control 22.1 Chapter 23 Air Systems: Minimum Ventilation and VAV System Controls 23.1 Chapter 24 Improving Indoor Air Quality 24.1 Chapter 25 Energy Management and Global Warming 25.1 Chapter 26 Air Conditioning Systems: System Classification, Selection, and Individual Systems 26.1 SH ST LG DF CONTENTS 39445 Wang (MCGHP) FM REV PAGES rg 08/15/00 pg ix CONTENTS ix RH TX Chapter 27 Air Conditioning Systems: Evaporative Cooling Systems and Evaporative Coolers 27.1 Chapter 28 Air Conditioning Systems: Space Conditioning Systems 28.1 Chapter 29 Air Conditioning Systems: Packaged Systems and Desiccant-Based Systems 29.1 Chapter 30 Air Conditioning Systems: Central Systems and Clean-Room Systems 30.1 Chapter 31 Air Conditioning Systems: Thermal Storage Systems 31.1 Chapter 32 Commissioning and Maintenance 32.1 Appendix A Nomenclature and Abbreviations A.1 Appendix B Psychrometric Chart, Tables of Properties, and I-P Units to SI Units Conversion B.1 Index follows Appendix B SH ST LG DF ... publication of ASHRAE Standard 90.1-1999 and ASHRAE Standard 62-1999, often called the Energy standard and Indoor Air Quality standard, the second edition of Handbook of Air Conditioning and Refrigeration. .. of Refrigeration Engineering and Air Conditioning as the teaching and learning package, and presented several papers at ASHRAE meetings The First Edition of the Handbook of Air Conditioning and. .. more complete concept of air conditioning, the term HVAC&R is often used by the industry 1.2 COMFORT AND PROCESSING AIR CONDITIONING SYSTEMS Air Conditioning Systems An air conditioning, or HVAC&R,