Testing and balancing HVAC air and water systems

Testing and Balancing

HVAC

Air and Water Systems

Fifth Edition

Testing and Balancing

HVAC

Air and Water Systems

Fifth Edition

Samuel C. Sugarman

Library of Congress Cataloging-in-Publication Data

Sugarman, Samuel C., 1946-

Testing and balancing HVAC air and water systems/Samuel C. Sugarman.--Fifth

edition.

pages cm

Includes index.

ISBN 0-88173-728-3 (alk. paper) -- ISBN 0-88173-729-1 (electronic) -- ISBN 978-1-

4822-5567-6 (taylor & francis distribution : alk. paper)

1. Heating--Equipment and supplies--Testing. 2. Ventilation--Equipment and

supplies--Testing. 3. Air conditioning--Equipment and supplies--Testing. 4. Balancing

of machinery. 5. Heat balance (Engineering) I. Title.

TH7015.M66 2014

697--dc23

2014008675

Testing and balancing HVAC air and water systems by Samuel C. Sugarman. Fifth edition

©2014 by The Fairmont Press, Inc. All rights reserved. No part of this publication

may be reproduced or transmitted in any form or by any means, electronic or

mechanical, including photocopy, recording, or any information storage and retrieval

system, without permission in writing from the publisher.

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ISBN 0-88173-728-3 (The Fairmont Press, Inc.)

ISBN 978-1-4822-5567-6 (Taylor & Francis Ltd.)

While every effort is made to provide dependable information, the publisher, au￾thors, and editors cannot be held responsible for any errors or omissions.

The views expressed herein do not necessarily reflect those of the publisher.

v

Contents

PART I

Chapter 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

General Balancing Procedure. . . . . . . . . . . . . . . . . . . . . .3

Preliminary Office Work. . . . . . . . . . . . . . . . . . . . . .3

Preliminary Field Inspection . . . . . . . . . . . . . . . . . . 4

Chapter 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Preliminary Air Balancing Procedures . . . . . . . . . . . . . . . 9

Preliminary Office Work. . . . . . . . . . . . . . . . . . . . . .9

Preliminary Field Inspection . . . . . . . . . . . . . . . . . 12

Motor Nameplate Information . . . . . . . . . . . . . . . . . 12

Drive Information . . . . . . . . . . . . . . . . . . . . . . . 14

Air Volume Readings

In the Air Handling Unit. . . . . . . . . . . . . . . . . . . . . 27

Chapter 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Air Balance Procedures Common to All Systems . . . . . . . . . 29

Balancing Principles . . . . . . . . . . . . . . . . . . . . . . . 29

Pitot Tube Traverse. . . . . . . . . . . . . . . . . . . . . . . . 29

Alternate Traverse Methods . . . . . . . . . . . . . . . . . . . 35

Velocity Pressure Readings . . . . . . . . . . . . . . . . . . 37

Calculating Air Volume . . . . . . . . . . . . . . . . . . . . 41

Density Corrections . . . . . . . . . . . . . . . . . . . . . . 42

Totaling the System. . . . . . . . . . . . . . . . . . . . . . . . 46

Chapter 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Balancing Constant Volume Low Pressure Systems . . . . . . 49

Instrumentation. . . . . . . . . . . . . . . . . . . . . . . . . . 49

Proportionally Balancing

Low Pressure Systems . . . . . . . . . . . . . . . . . . . . . . 50

Chapter 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Balancing Constant Volume Multizone, Dual Duct, and

Induction Systems . . . . . . . . . . . . . . . . . . . . . . . . 61

Multizone (Mz) Systems . . . . . . . . . . . . . . . . . . . . . 61

vi

Proportionally Balancing Zones . . . . . . . . . . . . . . . 62

Dual Duct (DD) Systems. . . . . . . . . . . . . . . . . . . . . 65

Induction Systems . . . . . . . . . . . . . . . . . . . . . . . 70

Chapter 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

Balancing Variable Air Volume Systems . . . . . . . . . . . . . . 73

Variable Air Volume (VAV) Systems . . . . . . . . . . . . . . 73

Types of Vav Systems . . . . . . . . . . . . . . . . . . . . . 74

Balancing Pressure Independent Systems . . . . . . . . . . . 74

Balancing Pressure Dependent Systems . . . . . . . . . . . . 78

Combination Systems . . . . . . . . . . . . . . . . . . . . . 81

VAV Troubleshooting Guidelines. . . . . . . . . . . . . . . . 82

Chapter 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

Setting Outside Air, Checking Economizer Operation,

and Changing Fan Speed and Drive Components . . . . . . . 87

Outside Air Considerations . . . . . . . . . . . . . . . . . . . 87

Setting Outside Air. . . . . . . . . . . . . . . . . . . . . . . . 87

Checking Economizer Operation. . . . . . . . . . . . . . . . 89

Calculating Fan Speed Changes . . . . . . . . . . . . . . . 90

Example Problems . . . . . . . . . . . . . . . . . . . . . . . . 91

Tip Speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

Additional Drive Information. . . . . . . . . . . . . . . . . . 93

Calculating Belt Size . . . . . . . . . . . . . . . . . . . . . . . 94

Changing Drive Components. . . . . . . . . . . . . . . . . . 95

Final Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

Chapter 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

Balancing Return Air and Toilet Exhaust Systems . . . . . . . 97

Return Air Systems. . . . . . . . . . . . . . . . . . . . . . . . 97

Toilet Exhaust Systems. . . . . . . . . . . . . . . . . . . . . 100

Chapter 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

Fans, Fan Performance Curves, and Duct System Curves . . . 103

Fan Operation. . . . . . . . . . . . . . . . . . . . . . . . . . 103

Fan Designations . . . . . . . . . . . . . . . . . . . . . . . . 103

Fan Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

Axial Fans . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

Centrifugal Fans . . . . . . . . . . . . . . . . . . . . . . . . 106

Special Design Fans . . . . . . . . . . . . . . . . . . . . . . 111

vii

Fan Performance Curves. . . . . . . . . . . . . . . . . . . . 112

Fan Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . 113

Fan Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114

Multiple Fan Arrangements. . . . . . . . . . . . . . . . . . .114

Duct System Curves . . . . . . . . . . . . . . . . . . . . . . .115

Fan Performance . . . . . . . . . . . . . . . . . . . . . . . . .117

Outlet Conditions . . . . . . . . . . . . . . . . . . . . . . . 118

Inlet Conditions. . . . . . . . . . . . . . . . . . . . . . . . . .119

PART II

Chapter 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

Testing and Balancing Fume Hood Systems . . . . . . . . . . . 123

Laboratory HVAC System. . . . . . . . . . . . . . . . . . . 123

Laboratory Fume Hoods. . . . . . . . . . . . . . . . . . . . 124

Testing and Balancing Laboratory Fume Hoods . . . . . . 128

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . 131

Terminology. . . . . . . . . . . . . . . . . . . . . . . . . . . 133

Chapter 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139

Testing and Balancing Cleanrooms . . . . . . . . . . . . . . . . 139

Cleanrooms . . . . . . . . . . . . . . . . . . . . . . . . . . . 139

Air System Test and Balance

Requirements, Procedures and Reports. . . . . . . . . . 142

Cleanroom Testing . . . . . . . . . . . . . . . . . . . . . . . 146

Cleanroom Test and Balance

Requirements, Procedures and Reports. . . . . . . . . . 148

Chapter 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153

HVAC Commissioning . . . . . . . . . . . . . . . . . . . . . . . 153

What Is HVAC Commissioning? . . . . . . . . . . . . . . . 153

Is There a Need for Experts in HVAC Commissioning?. . 153

HVAC Commissioning. . . . . . . . . . . . . . . . . . . . . 154

The HVAC Commissioning Team . . . . . . . . . . . . . . 154

The Test Engineer. . . . . . . . . . . . . . . . . . . . . . . . 155

The HVAC Commissioning Process . . . . . . . . . . . . . 155

Tab and HVAC Commissioning Schedules . . . . . . . . . 155

Job Site Inspections. . . . . . . . . . . . . . . . . . . . . . . 156

Field Test Procedures. . . . . . . . . . . . . . . . . . . . . . 156

Field Testing. . . . . . . . . . . . . . . . . . . . . . . . . . . 157

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159

viii

Chapter 13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161

Water Balance Procedures. . . . . . . . . . . . . . . . . . . . . . 161

Balancing Principles . . . . . . . . . . . . . . . . . . . . . . 161

Proportional Balancing Using Direct

Measurement Flow Meters. . . . . . . . . . . . . . . . . 162

Proportional Balancing

Using Differential Pressure . . . . . . . . . . . . . . . . . . 168

Proportional Balancing

Using Differential Temperatures . . . . . . . . . . . . . . . 172

Chapter 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177

Centrifugal Pumps and Pipe Systems. . . . . . . . . . . . . . . 177

Centrifugal Pumps . . . . . . . . . . . . . . . . . . . . . . . 177

Pump Operation . . . . . . . . . . . . . . . . . . . . . . . . 178

Multiple Pump Arrangements . . . . . . . . . . . . . . . . 178

Pump Performance Curves . . . . . . . . . . . . . . . . . . 179

Pipe System Curves . . . . . . . . . . . . . . . . . . . . . . 181

Operating Point. . . . . . . . . . . . . . . . . . . . . . . . . 182

Multiple Pump Arrangements . . . . . . . . . . . . . . . . 184

Net Positive Suction Head. . . . . . . . . . . . . . . . . . . 186

Primary-Secondary Circuits. . . . . . . . . . . . . . . . . . 188

Chapter 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191

Analog and Digital Automatic Controls . . . . . . . . . . . . . 191

Automatic Control System . . . . . . . . . . . . . . . . . . 191

Automatic Control Components . . . . . . . . . . . . . . . 191

Analog Controls . . . . . . . . . . . . . . . . . . . . . . . . 193

Pneumatic, Electric and Direct Digital Controls. . . . . . . 198

Digital Control . . . . . . . . . . . . . . . . . . . . . . . . . 198

Direct Digital Control Systems . . . . . . . . . . . . . . . . 199

DDC Controllers, Control Logic and Control Response. . 201

Variable Air Volume DDC Controls . . . . . . . . . . . . . 204

Testing and Balancing . . . . . . . . . . . . . . . . . . . . . 205

PART III

Chapter 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209

Fluid Flow, Psychrometric, and Refrigeration Terminology. . 209

Fluid Flow Terminology. . . . . . . . . . . . . . . . . . . . 209

ix

Psychrometric Terminology. . . . . . . . . . . . . . . . . . 210

Refrigeration Terminology . . . . . . . . . . . . . . . . . . 212

Chapter 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215

Air Systems: Distribution, Components

and Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 215

Chapter 18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233

Water Systems: Distribution, Components

and Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 233

Chapter 19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249

Fan, Pump, Drive, Motor, and Electrical Terminology . . . . . 249

Fan Terminology . . . . . . . . . . . . . . . . . . . . . . . . 249

Pump Terminology. . . . . . . . . . . . . . . . . . . . . . . 252

Drive Terminology . . . . . . . . . . . . . . . . . . . . . . . 260

Motor Terminology. . . . . . . . . . . . . . . . . . . . . . . 261

Electrical Terminology. . . . . . . . . . . . . . . . . . . . . 264

Chapter 20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267

Instruments and Instrument Terminology . . . . . . . . . . . . 267

Care and Use of Instruments . . . . . . . . . . . . . . . . . 267

Common Terms. . . . . . . . . . . . . . . . . . . . . . . . . 268

Air Instruments. . . . . . . . . . . . . . . . . . . . . . . . . 270

Electrical Instruments . . . . . . . . . . . . . . . . . . . . . 276

Rotational Speed Instruments. . . . . . . . . . . . . . . . . 278

Temperature Instruments . . . . . . . . . . . . . . . . . . . 279

Water Instruments . . . . . . . . . . . . . . . . . . . . . . . 280

Part Iv

Chapter 21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285

Equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285

Airflow. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285

Areas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 288

Belts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289

Circular Equivalents of Rectangular Duct. . . . . . . . . . 289

Drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 290

Electrical. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 290

x

Fans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 292

Fan Laws . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294

Fan Laws and Density . . . . . . . . . . . . . . . . . . . . . 298

Heat Transfer—Air. . . . . . . . . . . . . . . . . . . . . . . 298

Heat Transfer—Water . . . . . . . . . . . . . . . . . . . . . 300

Motors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300

Psychrometrics . . . . . . . . . . . . . . . . . . . . . . . . . 300

Pumps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301

Pump Laws . . . . . . . . . . . . . . . . . . . . . . . . . . . 304

Temperature. . . . . . . . . . . . . . . . . . . . . . . . . . . 305

Water Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . 308

Chapter 22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .311

Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 311

Altitude Pressure Table . . . . . . . . . . . . . . . . . . . . 311

General Conversion Table . . . . . . . . . . . . . . . . . . . .311

Water Property Table. . . . . . . . . . . . . . . . . . . . . . 313

Table of Cefapp Rules of Thumb, Factors, Etc. . . . . . . . 313

Conversion Table of Velocity and Velocity Pressures. . . . 317

Table of Associations and Organizations . . . . . . . . . . 319

PART V

Addendum. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 325

Chapter 1—General Balancing Procedure . . . . . . . . . . 325

Chapter 2—Preliminary Air Balancing Procedures. . . . . 340

Chapter 4—Balancing Constant Volume

Low Pressure Systems . . . . . . . . . . . . . . . . . . . 346

Chapter 5—Balancing Constant Volume

Multizone, Dual Duct, and Induction Systems . . . . . 353

Chapter 6—Balancing Variable Air Volume Systems . . . . 354

Chapter 7—Setting Outside Air, . . . . . . . . . . . . . . . 366

Checking Economizer Operation, and

Changing Fan Speed and Drive Components . . . . . . 366

Chapter 13—Water Balance Procedures . . . . . . . . . . . 368

Chapter 14—Centrifugal Pumps and

Hydronic Pipe Systems . . . . . . . . . . . . . . . . . . . 372

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 383

xi

Foreword

This book will provide the reader with an understanding of the

principles and practices of testing and balancing (TAB) heating, ventilat￾ing and air conditioning (HVAC) air and water systems. It is for anyone

interested in testing and balancing. For the novice and the experienced

testing and balancing technician it is a field reference book of proce￾dures, equations, and information tables. For those interested in getting

into TAB or are new to the HVAC industry it’s a text for learning more

about HVAC systems and testing and balancing. For the mechanical en￾gineer, building owner, facility manager or energy manager this book

can be used for teaching TAB, writing more effective specifications, and

learning about TAB and how it interacts with system commissioning,

indoor air quality and energy management. It is the intent of this book

to improve the communications between owners, mechanical engineers,

designers, vendors, contractors and TAB engineers, supervisors, and

technicians to ensure that HVAC systems are being properly tested and

balanced.

This book is used in test and balance self-study courses, in-house

training programs, seminars and other training formats as preparation

for TAB certification, and as a text in colleges and technical schools. The

fifth edition it is arranged in five parts. Part I has general and specific bal￾ancing procedures for constant air volume systems, variable air volume

systems, return air systems, and fans and fan performance in Chapters

1 through 9. The six chapters, 10-15, in Part II cover testing and balanc￾ing fume hood systems and cleanrooms, commissioning HVAC systems,

centrifugal pumps and pump performance, analog and digital controls

and water balancing procedures using flow meters, system components

and temperatures. Part III has five terminology chapters covering fans,

pumps, air distribution, water distribution, motors, electrical, fluid flow,

psychrometrics, refrigeration and instrument usage and care. Part IV,

Chapters 21 and 22, are equations and tables. Part V is an Addendum

with updated information and additional test and balance procedures

and graphics for Chapters 1 through 7, and Chapters 13 and 14.

In the process of reviewing this fifth edition for updates and revi￾sions I am also reviewing my own 35 years working in HVAC as a con￾sultant, instructor and author in test and balance, system performance

xii

evaluation, energy management, system design, system retrofit, indoor

air quality, and commissioning for large office complexes, hotels, hos￾pitals, fume hood labs, cleanroom facilities, major retail establishments,

military installations, nuclear power plants, manufacturing facilities,

colleges and universities, private and public schools, and government

facilities.

I now serve as CTAB board chairman for the International Registry

for CTAB Professionals (irctab.org). My company, Sugarman Consulting,

is a Training Organization for IRCTAB and teaches the CTAB certifica￾tion program.

As always, I commend you for your pursuit of knowledge and ex￾cellence in HVAC, TAB and related industries and your commitment to

provide the highest quality of service.

Sam Sugarman, CTAB, CEM

CTAB Board Chairman, irctab.org

The Certified Testing Adjusting Balancing (CTAB) Professional Achievement

certification provides special recognition for professionals who demonstrate a

high level of knowledge, experience, competence, and ethical fitness covering

the full spectrum of activities related to the testing, adjusting and balancing of

HVAC systems. CTAB Certification recognizes Elite Professionals in manage￾ment, supervision, design, selection and testing adjusting balancing the quanti￾tative fluid flow performance of HVAC systems.

xiii

Introduction

Testing and balancing can be interesting and challenging. But, it

can also be difficult and sometimes frustrating because air and water

systems will have complications due to design, installation, and equip￾ment selection. You may encounter:

• Improper or too few balancing dampers in air systems

• Water systems without flow meters or balancing valves

• Duct and pipe systems without enough straight duct and pipe to

obtain accurate flow quantity measurements

• Fan and pump “system effect” caused by restrictive or extensive air

ducts and water piping which hamper the flow of air and water

• Ducts with large aspect ratios

• Leaks in air ducts, water pipes, dampers, air valves and water

valves

• Uninsulated ducts and pipes which increase the loss of thermal en￾ergy

• Ducts and pipes installed incorrectly, e. g., supplies connected to

returns, etc.

• Improper air mixing in the air handling unit or in the conditioned

space or improper water mixing at the boiler, water cooler or con￾denser

• Failure of the system to supply the proper air and water tempera￾tures to terminals and the controlled space

• Limited or no control of the system or the conditioned space be￾cause of improper location, calibration or operation of tempera￾ture, pressure or humidity sensors and controllers

• Problems with constant volume and variable volume control sys￾tems at the air handling unit chiller, boiler, or air or water distribu￾tion system

xiv

• Increased energy use or decreased potential energy savings by im￾proper closing dampers in air systems or valves in water systems

instead of reducing fan speed or pump impeller size

What do you do in these cases? First, discuss the problem with “the

authorized responsible person.” Offer solutions and wait for direction. If

appropriate, continue working the project getting as many varied read￾ings as necessary to satisfy yourself that you can honestly say what the

flow quantities are and how the system is operating. In other words, you

do the best that you can with what you have, realizing that sometimes a

system can’t be balanced to design quantities, temperatures, humidities,

flow patterns, etc. Bottom line; inform owners, engineers or contractors

of the problems with equipment, design or installation and work with

them to get the system operating at the maximum condition possible.

This book is based on my field and teaching experience in testing,

balancing, designing and evaluating HVAC systems. There are two ba￾sic methods of balancing. One method is balancing from the terminals

back to the fan or pump. This method is proportional balancing. It was

during a job at a nuclear power plant many years ago that I first started

using the proportional method that I’ve outlined in this text. Because we

couldn’t get enough experienced balancing technicians for the project, I

began instructing sheet metal mechanics with little or no balancing back￾ground in proportional balancing. I found that the proportional method

was quickly learned in a classroom setting and then applied to the field.

The proportional method (1) follows a scientific approach with predict￾able results, (2) establishes a starting point and allows others with pro￾portional balancing experience to come in and take over the balancing

when the need arises, (3)large systems are balanced quicker, and (4)the

least resistance is imposed on the system while delivering air or water

to the terminals at design or at the highest possible flow quantities. I’ve

continued to teach this method in my classes, seminars and in-house

training programs and now with the CTAB program with great success.

I’m sure it’ll work for you as well.

In the chapters on proportional balancing, I’ve used the term per￾cent of design (%D). This is meant for new construction where balancing

is done by an agency according to the fluid quantities specified on the

contract documents. These numbers are based on expected heating and

cooling loads. However, %D can also stand for percent of desired flow

quantity. This is used for in-house balancing or balancing to owners’