PROCEDURAL STANDARDS FOR TESTING ADJUSTING AND BALANCING OF ENVIRONMENTAL SYSTEMS 2005 – SEVENTH EDITION NATIONAL ENVIRONMENTAL BALANCING BUREAU PROCEDURAL STANDARDS FOR TESTING ADJUSTING AND BALANCING OF ENVIRONMENTAL SYSTEMS 2005 – SEVENTH EDITION National Environmental Balancing Bureau 8575 Grovemont Circle Gaithersburg, Maryland 20877-4121 301-977-3698 301-977-9589 FAX www.nebb.org PROCEDURAL STANDARDS FOR TESTING, ADJUSTING, AND BALANCING OF ENVIRONMENTAL SYSTEMS ©Copyright NEBB, 2005 FIRST EDITION - JANUARY 1972 SECOND EDITION - JANUARY 1977 THIRD EDITION - APRIL 1981 FOURTH EDITION - SEPTEMBER 1983 FIFTH EDITION - JULY 1991 SIXTH EDITION - FEBRUARY 1998 SEVENTH EDITION - JANUARY 2005 This book may not be reproduced in any form without written permission of the copyright owner. These Procedural Standards were developed using reliable engineering principles and research plus consultation with, and information obtained from, manufacturers, users, testing laboratories and others having specialized experience. They are subject to revision as further experience and investigation may show is necessary or desirable. System balancing, which complies with these Procedural Standards, will not necessarily be acceptable, if when examined and tested, it is found to have other features that impair the result intended by these standards. The National Environmental Balancing Bureau assumes no responsibility and has no liability for the application of the principles or techniques contained in these Procedural Standards. Authorities considering adoption of these Procedural Standards should review all Federal, State, local and contract regulations applicable to the specific installation. II FOREWORD The purpose of the NEBB Procedural Standards for Testing Adjusting and Balancing of Environmental Systems is to establish a uniform and systematic set of criteria for the performance of the testing, adjusting and balancing of environmental or Heating, Ventilating and Air-conditioning (HVAC) systems. Today’s buildings provide highly controlled indoor environments. These conditions could not exist without sophisticated mechanical systems created by a team of skilled professionals. A key member of this team is the NEBB Certified Test, Adjust, and Balance (TAB) Firm. This Seventh Edition represents a departure from past editions and is divided into two distinct Parts: Standards and Procedures. These TAB procedural standards have been developed using language defined by “Shall, Should, and May” as it relates to the standards and procedures described in this manual. It is important to note these particular words throughout this manual and how they pertain to the NEBB standards and procedures. These standards and procedures are intended as the minimum NEBB requirements that a NEBB Certified TAB Firm shall follow when performing Testing, Adjusting, and Balancing procedures. Contract documents may supercede the NEBB requirements. These TAB Procedural Standards have been carefully compiled and reviewed by the NEBB Technical Committees. Part 1 STANDARDS Part 1, STANDARDS, covers the requirements for Quality Control and Compliance, Instrumentation Requirements, and TAB Reports. Revised requirements for TAB instruments and reports are identified. The new report requirements allow the NEBB Certified Firm more flexibility in designing their reports by prescribing sets of information that "Shall, Should and/or May" be required to complete a TAB Report. Part 2 PROCEDURES Part 2, PROCEDURES, covers measurement procedures and the testing, adjusting and balancing of both air and hydronic distribution systems. APPENDICES The Appendices include an overview of TAB Instrumentation, a Pre–TAB Checklist, and a suggested TAB Specification. This Seventh Edition of the TAB Procedural Standards, when used by NEBB Certified TAB Firms, will assure the building owner or operator a properly balanced environmental system within design and installation limitations. Andrew P. Nolfo, P.E. NEBB Technical Director III TESTING, ADJUSTING AND BALANCING COMMITTEE MEMBERS AND OTHER CONTRIBUTORS FOR CURRENT AND PREVIOUS EDITIONS Current TAB Committee: Past Contributors: Al Fudge, Chairman William C. Abernathy * Dan Langford* Issaquah, Washington Rockville, Maryland Jacksonville, Florida Joseph Miller, Past Chairman Wade Adams Thomas LoScalzo, P.E. Alton, Virginia Redwood City, California Olathe, Kansas Martin A. Cirillo James R. Bell P.E. Michael Margolis Baja California Dallas, Texas Brentwood, Maryland Eric Jenison Robert M. Bolton Bruce Meyer, P.E. Deerfield Beach, Florida Pawtucket, Rhode Island St. Paul, Minnesota Jim Oxner, P.E. William T. Bride, Jr Ted Salkin, P.E. Shreveport, Louisiana Lawrence, Massachusetts Philadelphia, Pennsylvania Greg Sharkey James S. Barrie, P.E. Al Scavino, P.E. Fort Worth, Texas Denver, Colorado Richmond, California Paul Chasteauneuf Willard W. Brockway William E. Simmons Moorabbin, Victoria, Australia Denver, Colorado Kansas City, Kansas W. David Bevirt, P.E Raymond (Jack) Fulton James A. Smith Tucson, Arizona Indianapolis, Indiana Santa Rosa, California Andrew P. Nolfo, P.E Stephen Holzinger George Theisen Phoenix, Arizona Indianapolis, Indiana Greensboro, North Carolina Edward Halady B. Wesley Thornburg Buffalo, New York Memphis, Tennessee George Hightower, P.E.* Ted H. Turner Atlanta, Georgia Memphis, Tennessee Raymond Jung Daniel Whalen Baltimore, Maryland Pittsburgh, Pennsylvania Lester Lang Mel Wind. P.E.* St. Louis, Missouri Philadelphia, Pennsylvania Additional Contributors to the Seventh Edition: Robert Gleeson, P.E Marty Loft Fred Menger Universal City, Texas Milton, Washington Minneapolis, Minnesota Mike Dolim Gaithersburg, Maryland * DECEASED IV TABLE OF CONTENTS PAGE Foreword III NEBB Testing and Balancing Committee IV Table of Contents V PART 1 – STANDARDS SECTION 1 Definitions 1 SECTION 2 NEBB Program, Quality Control and Compliance 2.1 NEBB Programs 5 2.1.1 NEBB Disciplines 5 2.1.2 Firm Certification 5 2.1.3 Supervisor Qualification 5 2.1.4 Recertification Requirements 6 2.1.5 NEBB Qualified Technicians 6 2.2 Quality Assurance Program – Conformance Certification 6 2.2.1 Program Advantages 6 2.2.2 NEBB Quality Assurance Program Certificate 6 2.3 Quality Control and Compliance 6 2.3.1 TAB Work Compliance 6 2.4 TAB Supervisor Responsibilities 7 2.4.1 Execution of TAB Procedures 7 2.4.2 NEBB Technician Training 7 2.4.3 TAB Procedures Training 7 2.4.4 Instrument Use and Maintenance 7 2.4.5 Coordination / Supervision 8 2.4.6 Project Communication 8 2.4.7 Completion of Procedures 8 2.4.8 Compilation and Submission of Final TAB Reports 8 SECTION 3 Responsibilities 3.1 Introduction 9 3.2 Design and Construction Team Responsibilities 9 3.2.1 Design Professional Responsibilities 9 3.2.2 Construction Team Responsibilities 9 3.2.3 NEBB Certified TAB Firm Responsibilities 10 SECTION 4 Standards for Instrumentation and Calibration 4.1 Minimum Instrumentation 11 4.2 Range and Accuracy 11 Table 4-1 Instrumentation Requirements (US Units) 12 Table 4-1 Instrumentation Requirements (SI Units) 13 V NEBB TAB PROCEDURAL STANDARDS TABLE OF CONTENTS PAGE SECTION 5 Standards for Reports and Forms 5.1 Reports 15 5.2 Required Forms 15 5.2.1 Report Title 15 5.2.2 Report Certification 16 5.2.3 Table of Contents 16 5.2.4 Report Summary / Remarks 16 5.2.5 All Report Pages 16 5.2.6 Instrument Calibration 16 5.2.7 Abbreviations 17 5.3 Air Handling Unit Test Data (Central Station) 17 5.4 Air Handling Unit Test Data (Package / Unitary Belt Drive) 18 5.5 Air Handling Unit Test Data (Package / Unitary Direct Drive) 18 5.6 Fan Test Data (Belt Drive) 19 5.7 Fan Test Data (Direct Drive) – 1/6 HP and greater 20 5.8 Fan Test Data (Direct Drive) – less than 1/6 HP 20 5.9 Air Outlet Test Data (All) 21 5.10 Variable Volume Terminal Test Data (Pressure Dependent) 21 5.11 Variable Volume Terminal Test Data (Pressure Independent) 21 5.12 Fan Powered Terminal Test Data (Pressure Dependent) 22 5.13 Fan Powered Terminal Test Data (Pressure Independent) 22 5.14 Duct Traverse Test Data 22 5.15 Hydronic Pump Test Data 23 5.16 Hydronic Balancing Valve Test Data (Fixed or Adj. Orifice) 23 5.17 Hydronic Balancing Valve Test Data (Self-adjusting) 24 5.18 Ultrasonic Flow Measurement Test Data 24 5.19 Cooling Coil Test Data (Hydronic) 24 5.20 Cooling Coil Test Data (DX) 25 5.21 Heating Coil Test Data (Hydronic) 25 5.22 Heating Coil Test Data (Steam) 26 5.23 Heating Coil Test Data (Electric) 26 5.24 Chiller Test Data (Water Cooled) 26 5.25 Chiller Test Data (Air Cooled) 27 5.26 Compressor / Condenser Test Data 27 5.27 Cooling Tower Test Data 27 5.28 Hot Water Boiler Test Data 28 5.29 Heat Exchanger Test Data (Water to Water) 28 5.30 Heat Exchanger Test Data (Steam to Water) 29 5.31 Energy Recovery Wheels 29 5.32 Duct Air Leakage Test Data (Optional) 30 VI NEBB TAB PROCEDURAL STANDARDS TABLE OF CONTENTS PART 2 - PROCEDURES PAGE SECTION 6 Basic TAB Measurements 6.1 Introduction 31 6.2 Air Pressure Procedures 31 6.2.1 Instruments 31 6.2.2 General Measurement Techniques 32 6.2.3 Specific Measurement Techniques 32 6.3 Air Velocity Procedures 32 6.3.1 Instruments 33 6.3.2 General Measurement Techniques 33 6.3.3 Specific Measurement Techniques 33 6.3.4 Face Velocity Measurements 34 6.4 Temperature Measurement Procedures 35 6.4.1 Instruments 35 6.4.2 General Measurement Techniques 36 6.4.3 Specific Measurement Techniques 36 6.5 Flow Measuring Hood Procedures 38 6.5.1 Instruments 38 6.5.2 General Measurement Techniques 38 6.5.3 Specific Measurement Techniques 38 6.6 Rotational Speed Measurement Procedures 39 6.6.1 Instruments 39 6.6.2 Safety Considerations 39 6.6.3 General Measurement Techniques 39 6.6.4 Specific Measurement Techniques 39 6.7 Hydronic Pressure Procedures 40 6.7.1 Hydronic Pressure Measurements 40 6.7.2 Instruments 40 6.7.3 General Measurement Techniques 40 6.7.4 Specific Measurement Techniques 40 6.8 Electrical Measurements 41 6.8.1 Instruments 41 6.8.2 Safety 41 6.8.3 General Measurement Techniques 42 6.8.4 Specific Measurement Techniques 42 6.8.5 Variable Frequency Drives 44 SECTION 7 Preliminary TAB Procedures 7.1 Introduction 45 7.2 Planning 45 7.3 Preliminary TAB Procedures 45 SECTION 8 Air System TAB Procedures 8.1 Introduction 47 8.2 Preliminary System Procedures 47 VII NEBB TAB PROCEDURAL STANDARDS TABLE OF CONTENTS PAGE 8.3 Establishing Fan Total Airflow 48 8.4 Basic Air System Balancing Procedures 48 8.4.1 Proportional Method (Ratio Method) 49 8.4.2 Stepwise Method 50 8.5 Constant Volume Supply Systems 51 8.5.1 Basic Constant Volume Systems 51 8.5.2 Complex Constant Volume Systems 53 8.5.3 Systems With Power Exhaust 53 8.5.4 Systems With Return / Exhaust Fans 53 8.6 Multizone Systems 54 8.7 Induction Unit Systems 55 8.7.1 Operation 55 8.7.2 Procedures 55 8.8 Variable Volume System Overview 56 8.8.1 Diversity 56 8.8.2 Terminal Units (VAV Boxes) 56 8.8.3 Cooling Only Units 56 8.8.4 Cooling Only Units With Reheat 56 8.8.5 Fan Powered VAV Terminal Units 56 8.8.6 Dual Duct Terminal Units 57 8.8.7 Constant Volume (VAV) Terminal Units 57 8.8.8 Induction VAV Terminal Units 57 8.9 Variable Air Volume System Procedures 58 8.9.1 Pressure Dependent VAV Unit Procedures Without Diversity 58 8.9.2 Pressure Dependent VAV Unit Procedures With Diversity 60 8.9.3 Pressure Independent VAV Unit Procedures Without Diversity 62 8.9.4 Pressure Independent VAV Unit Procedures With Diversity 64 8.9.5 Combination Systems 64 8.10 Dual Duct Systems 64 8.10.1 Constant Volume Dual Duct Systems 64 8.10.2 Variable Volume Dual Duct Systems 66 8.11 Variable Volume Terminal Unit Procedures 66 8.11.1 Cooling Only Terminal Units 66 8.11.2 Cooling Only Terminal Units With Reheat 67 8.11.3 Fan Terminal VAV Units 67 8.11.4 Dual Duct Terminal Units (Constant or Variable Volume) 68 8.12 Underfloor Plenum Supply Air Systems 68 8.13 Return Air Systems 69 8.14 Exhaust Air Systems 69 8.14.1 General Exhaust Air Systems 69 8.14.2 Kitchen Exhaust Air / Makeup Air Systems 69 8.15 Laboratory Fume Hoods 69 8.15.1 Fume Hood Performance 69 8.15.2 Fume Hood Performance Testing 70 8.15.3 Face Velocity Measurement Procedures 70 8.15.4 Visual Method Procedures (If Required) 71 VIII NEBB TAB PROCEDURAL STANDARDS TABLE OF CONTENTS PAGE 8.16 Biosafety Cabinets 71 8.17 Industrial Exhaust Hoods and Equipment 72 8.17.1 Air and Fume Hood Exhaust 72 8.17.2 Material Handling Systems 72 8.18 Building Static Control Methods 72 8.18.1 Active Building Static Pressure Control 73 8.18.2 Open Loop Control 73 8.18.3 Closed Loop Control (Fan Tracking) 73 8.19 Stairwell Pressurization Testing 73 8.20 Elevator Pressurization Testing 74 SECTION 9 Hydronic System TAB Procedures 9.1 Introduction 77 9.2 Preliminary System Procedures 77 9.3 Hydronic System Measurement Methods 77 9.3.1 Basic Flow Measurement Methods 77 9.3.2 Calibrated Flow Measuring Devices 78 9.3.3 Calibrated Balancing Valves 78 9.3.4 Pump Curve Method 79 9.3.5 Equipment Pressure Loss Method 79 9.3.6 Heat Transfer Method 79 9.4 Basic Hydronic System Procedures 80 9.4.1 Proportional Balancing Method (Ratio Method) 80 9.4.2 Stepwise Balancing Method 82 9.4.3 Systems With Self Adjusting Valves 83 9.5 Hydronic System Balancing Procedures 83 9.5.1 Basic Procedures 83 9.5.2 Bypass Valves 84 9.5.3 Variable Volume Hydronic Systems 85 9.5.4 Primary – Secondary Hydronic Systems 86 9.6 Balancing Specific Systems 87 9.6.1 Cooling Tower (Condenser Water) Systems 87 9.6.2 Chilled Water Systems 87 9.6.3 Heat Exchangers and Boiler Systems 88 9.6.4 Heat Transfer Components 88 SECTION 10 Outdoor Air Ventilation Procedures 10.1 Introduction 91 10.2 Measurement Options 91 10.2.1 Direct Measurement Method 91 10.2.2 Mixed Air Temperature Method 91 IX