ASHRAE POCKET GUIDE for air conditioning

ASHRAE POCKET GUIDE for air conditioning 2013: climate data properties for new refrigerants, new data on refrigerant safety, ventilation requirements for residential and nonresidential occupancies, occupant thermal comfort, extensive data on sound and vibration control, thermal storage, radiantpanel heating and cooling, airtoair energy recovery, space air diffusion data, equipment heat load data, combustion turbines, fuel cells, ultraviolet lamp systems, and more

2013PocketGuides.book Page i Tuesday, October 7, 2014 12:44 PM © 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 ASHRAE POCKET GUIDE for Air Conditioning, Heating, Ventilation, Refrigeration (I-P Edition) 8th Edition ASHRAE · 1791 Tullie Circle, NE Atlanta, GA 30329 · www.ashrae.org further reprodu 2013PocketGuides.book Page ii Tuesday, October 7, 2014 12:44 PM © 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 © 1987, 1989, 1993, 1997, 2001, 2005, 2009, 2013 ASHRAE All rights reserved Printed in the United States of America ISBN 978-1-936504-62-6 Product code: 90074 10/14 ASHRAE is a registered trademark in the U.S Patent and Trademark Office, owned by the American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc No part of this manual 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, photocopying, recording, or other—without permission in writing from ASHRAE Requests for permission should be submitted at www.ashrae.org/permissions ASHRAE has compiled this publication with care, but ASHRAE has not investigated, and 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 this 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 Library of Congress Cataloging-in-Publication Data ASHRAE pocket guide for air conditioning, heating, ventilation, refrigeration 8th edition, I-P edition pages cm Includes index Summary: "Ready reference for HVAC engineers whose mobility keeps them from easy access to the ASHRAE Handbooks; revised from 2009 edition, includes information from Handbooks and ASHRAE Standards 62.1, 62.2, 15, and 55 abridged or reduced to fit smaller page size" Provided by publisher ISBN 978-1-936504-62-6 (softcover : alk paper) Heating Equipment and supplies Handbooks, manuals, etc Ventilation Handbooks, manuals, etc Air conditioning Handbooks, manuals, etc Refrigeration and refrigerating machinery-Handbooks, manuals, etc I American Society of Heating, Refrigerating and Air-Conditioning Engineers II Title: Pocket guide for air conditioning, heating, ventilation, refrigeration TH7011.P63 2013 697.9'2 dc23 2013044820 ASHRAE Staff Special Publications 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 Publishing Services David Soltis, Group Manager of Publishing Services and Electronic Communications Jayne Jackson, Publication Traffic Administrator Tracy Becker, Graphics Specialist Publisher W Stephen Comstock Updates/errata for this publication will be posted on the ASHRAE Web site at www.ashrae.org/publicationupdates Errata noted in the list dated 08/6/2014 have been corrected further reprodu 2013PocketGuides.book Page iii Tuesday, October 7, 2014 12:44 PM © 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 CONTENTS Preface viii Air Handling and Psychrometrics Air Friction Chart Velocities vs Velocity Pressures Noncircular Ducts Fittings and Flexible Ducts Duct Leakage 3–4 Fitting Losses Circular Equivalents of Rectangular Ducts 6–7 Flat Oval Duct Equivalents Velocities for HVAC Components Fan Laws 10–11 Types of Fans 12–13 Fan System Effect 14 Psychrometric Chart 15 Air-Conditioning Processes 16–17 Enthalpy of Air 18 Standard Atmospheric Data 19 Moist Air Data 19 Space Air Diffusion 20–21 Principles of Jet Behavior 22–24 Airflow Patterns of Different Diffusers 25 Mixed-Air Systems 26 Fully Stratified Systems 31–32 Partially Mixed Systems 33–34 Return Air Design 35 Air Contaminants and Control Air Quality Standards 36 Electronic Air Cleaners 37 Bioaerosols 37 Filter Installations 37 MERV Parameters 38 Filter Application Guidelines 39 Indoor Contaminant Sources 40–42 Gaseous Contaminants by Building Materials 43–44 Ultraviolet Lamp Systems 45–46 Hood Capture Velocities 47 Exhaust Duct Design and Construction 47–50 Contaminant Transport Velocities 49 Hood Entry Loss 50 Kitchen Ventilation 51–53 Laboratory Hoods 54 Clean Spaces 55 Airborne Particle Concentration Limits 56 Water Pump Terms and Formulas 57 Pump Affinity Laws 57 Application of Affinity Laws 58 Net Positive Suction Characteristics 59–60 Typical Pump Curves 61 General Information on Water 62 Mass Flow and Specific Heat of Water 63 Freezing Points of Glycols 63 Vertical Cylindrical Tank Capacity 64 iii further reprodu 2013PocketGuides.book Page iv Tuesday, October 7, 2014 12:44 PM © 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 Horizontal Cylindrical Tank Capacity 64 Volume of Water in Pipe and Tube 65 Water Pipe Friction Chart, Copper 66 Water Pipe Friction Chart, Plastic 67 Water Pipe Friction Chart, Steel 68 Friction Losses in Pipe Fittings 69–74 Steam Steam Table 75 Steam Chart 76 Steam Pipe Flow Rate 77 Steam Pipe Capacities 78–79 Steam Pipe Capacities—Return Mains and Risers 80 Piping Steel Pipe Data 81–83 Copper Tube Data 84–86 Properties of Plastic Pipe Materials 87–88 Pipe, Fitting, and Valve Applications 89–90 Thermal Expansion of Metal Pipe 91 Hanger Spacing and Rod Sizes 92 Service Water Heating Service Water Heating System Elements 93 Legionella pneumophila 93 Load Diversity 94–95 Hot-Water Demand for Buildings 96 Hot-Water Demand per Fixture 97–99 Hot-Water Flow Rate 100 Solar Energy Use Solar Irradiation 101–102 Solar Collector Data 103 Solar Heating Systems 104–105 Refrigeration Cycles Coefficient of Performance (COP) 106 Vapor Compression Cycle 107–108 Absorption Refrigeration 109 Lithium Bromide Chiller Characteristics 110 Refrigerants Refrigerant Data 111 Pressure-Enthalpy Chart—R-22 112 Property Tables—R-22 113–14 Pressure-Enthalpy Chart—R-123 115 Property Table—R-123 116 Pressure-Enthalpy Chart—R-134a 117 Property Tables—R-134a 118–19 Pressure-Enthalpy Chart—R-717 (Ammonia) 120 Property Tables—R-717 (Ammonia) 121 Pressure Enthalpy Chart—R-404A 122 Property Table—R-404A 123 Pressure Enthalpy Chart—R-407C 124 Property Table—R-407C 125 Pressure Enthalpy Chart—R-410A 126 Property Table—R-410A 127 Pressure Enthalpy Chart—R-507A 128 Property Table—R-507A 129 Pressure Enthalpy Chart—R-1234yf 130 iv further reprodu 2013PocketGuides.book Page v Tuesday, October 7, 2014 12:44 PM © 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 Property Table—R1234yf 131 Pressure Enthalpy Chart—R-1234ze(E) 132 Property Table—R-1234ze(E) 133 Comparative Refrigerant Performance 134–35 Refrigerant Line Capacities—R-404A 136–37 Refrigerant Line Capacities—R-507A 138–39 Refrigerant Line Capacities—R-410A 140–41 Refrigerant Line Capacities—R-407C 142–43 Refrigerant Line Capacities—R-22 144–45 Refrigerant Line Capacities—R-134a 146–47 Oil Entrained in Suction Risers—R-22 and R-134a 148–49 Oil Entrained in Hot-Gas Risers—R-22 and R-134a 150–51 Refrigerant Line Capacities—Ammonia (R-717) 152 Liquid Ammonia Line Capacities 153 Lubricants in Refrigerant Systems 154 Secondary Coolants 154 Relative Pumping Energy 154 10 Refrigerant Safety Safety Group Classification 155 Data and Safety Classifications for Refrigerants and Blends 156–57 ASHRAE Standard 15-2010 158–64 11 Refrigeration Load Transmission Load 165 Product Load 166 Internal Load 167 Infiltration Air Load 167 Equipment-Related Load 168 Safety Factor 168 Forced-Circulation Air Coolers 169 12 Air-Conditioning Load Data Cooling and Heating Loads 170–71 Cooling Load Check Values 172 Cooling Load Computation Procedure 173 Heat Flow Through Building Materials 174 Thermal Resistance of Plane Air Spaces 175 Surface Conductances and Resistances 176 Emissivity 177 Thermal Resistance of Ventilated Attics 178 Thermal Properties of Materials 179–84 CLTDs for Flat Roofs 185–86 CLTDs for Sunlit Walls 187–88 Solar Cooling Load for Sunlit Glass 189 Shading Coefficients for Glass 190 Heat Gain from People 191 Heat Gain from Lighting and LPDs 192–94 Heat Gain from Motors 195–96 Heat Gain from Restaurant Equipment 197–201 Heat Gain from Hospital and Laboratory Equipment 202–203 Heat Gain from Office Equipment 204–207 Display Fixtures Refrigerating Effect 207 13 Ventilation ASHRAE Standard 62.2-2010 208 ASHRAE Standard 62.1-2010 209–11 Procedures from ASHRAE Standard 62.1-2010 211–20 Normative Appendix A from ASHRAE Standard 62.1-2010 221–23 v further reprodu 2013PocketGuides.book Page vi Tuesday, October 7, 2014 12:44 PM © 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 Design Parameters for Health Care Facilities 224–25 Operation and Maintenance 226 14 Energy-Conserving Design Sustainability 227 Energy Efficiency Standards 228 Climate Zones for United States Locations 229 15 Electrical Characteristics of AC Motors 230 Motor Full-Load Amperes 231 Useful Electrical Formulas 231 Motor Controllers 232 Variable-Speed Drives (VSDs) 232 Photovoltaic Systems 233 16 Sorbents and Desiccants Desiccant Cycle 234 Desiccant Equipment 235 Desiccant Dehumidification 236 Rotary Solid Desiccant Dehumidifier Model 237–39 17 Combined Heat and Power Systems CHP Cycles 240 Engine Sizing Tables 241 Recommended Engine Maintenance 242 Gas Engine Chiller Performance 242 Engine Heat Balance 243 Energy Boundary Diagram 244 Heating Application Temperatures 244 Mass Flows and Temperatures for Various Engines 244 Steam Rates for Steam Turbines 245 Combustion Turbines 246 Fuel Cells 247–48 18 Fuels and Combustion Gas Pipe Sizing Table 249 Viscosity and Heating Values of Fuels 249–50 Liquid Fuels for Engines 251–52 Fuel Oil Pipe Sizing Tables 252 19 Owning and Operating Maintenance Costs 253–54 Owning and Operating Cost Data 255 Economic Analysis 256–57 20 Sound Sound Pressure and Sound Pressure Levels 258 Combining Sound Levels 259 Sound Power and Sound Power Level 259 A- and C- Weighting 259 Octave bands and 1/3 Octave Bands 260 Design Guidance for HVAC System Noise 261 Sound Rating Methods 262–63 Sound Paths in HVAC Systems 263 Silencers 264 Outlet Configurations 264 Mechanical Equipment Noise Levels 265 Mechanical Equipment Sound Isolation 265–66 vi further reprodu 2013PocketGuides.book Page vii Tuesday, October 7, 2014 12:44 PM © 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 21 Vibration Single-Degree of Freedom Systems 267 Two-Degree of Freedom Systems 267 Isolator Selection 268–78 22 Evaporative Cooling Direct Evaporative Air Coolers 279 Indirect Evaporative Air Coolers 280–81 Multistage Evaporative Coolers 282 Effective Temperature Chart 283 23 Automatic Controls HVAC System Components 284–90 HVAC Systems 291–92 24 Occupant Comfort ASHRAE Standard 55-2010 293 Graphic Comfort Zone Method 293 Operative and Effective Temperature 293 Predicted Mean Vote 293 Air Speed to Offset Temperature 294 Clothing Insulation Values 295 Local Discomfort 295–96 Thermal Comfort in Naturally Ventilated Buildings 296 25 Geothermal Systems Ground-Source Heat Pumps 297–299 Thermal Properties of Soils and Rocks 299–300 Ground Piping 300–302 Surface Water Piping 303 26 General System Design Criteria 304–305 SI Units and Air-Conditioning Formulas 308 Sizing Formulas for Heating/Cooling 309 Cooling Tower Performance 310 Thermal Storage 311–12 Cold-Air Distribution 313 Mechanical Dehumidifiers 313 Heat Pipes 314–15 Air-to-Air Energy Recovery 316–18 Panel Heating and Cooling 319–20 Variable Refrigerant Flow 321–23 Units and Conversions 324–25 Index .326–27 vii further reprodu 2013PocketGuides.book Page viii Tuesday, October 7, 2014 12:44 PM © 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 PREFACE The ASHRAE Pocket Guide was developed to serve as a ready, offline reference for engineers without easy access to the large ASHRAE Handbook volumes Most of the information is taken from the four volumes of the ASHRAE Handbook series, as well as from various ASHRAE Standards, and abridged or reduced to fit the smaller page size This eighth edition, revised and expanded for 2013, includes properties for new refrigerants, new data on refrigerant safety, ventilation requirements for residential and nonresidential occupancies, occupant thermal comfort, extensive data on sound and vibration control, thermal storage, radiant-panel heating and cooling, air-to-air energy recovery, space air diffusion data, equipment heat load data, combustion turbines, fuel cells, ultraviolet lamp systems, variable refrigerant flow, and more This edition of the ASHRAE Pocket Guide, which was first published in 1987, was compiled by ASHRAE staff editors; previous major contributors were Carl W MacPhee, Griffith C Burr, Jr., Harry E Rountree, and Frederick H Kohloss Throughout this Pocket Guide, original sources of figures and tables are indicated where applicable For space concerns, a shorthand for ASHRAE publications has been adopted ASHRAE sources are noted after figure captions or table titles in brackets using the following abbreviations: Fig Tbl Ch Std 2013F, 2009F, etc 2012S, 2008S, etc 2011A, 2007A, etc 2010R, 2006R, etc Figure Table Chapter ASHRAE Standard ASHRAE Handbook—Fundamentals ASHRAE Handbook—HVAC Systems and Equipment ASHRAE Handbook—HVAC Applications ASHRAE Handbook—Refrigeration viii further reprodu 2013PocketGuides.book Page Tuesday, October 7, 2014 12:44 PM © 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 AIR HANDLING AND PSYCHROMETRICS Figure 1.1 Air Handling and Psychrometrics Friction Chart for Round Duct (ρ = 0.075 lbm/ft3 and ε = 0.0003 ft) [2013F, Ch 21, Fig 10] further reprodu 2013PocketGuides.book Page Tuesday, October 7, 2014 12:44 PM © 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 Air Handling and Psychrometrics Table 1.1 Velocities vs Velocity Pressures Velocity V, fpm 300 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 2300 2400 2500 Velocity Pressure Pv , in H2O 0.01 0.01 0.02 0.02 0.03 0.04 0.05 0.06 0.08 0.09 0.11 0.12 0.14 0.16 0.18 0.20 0.22 0.25 0.27 0.30 0.33 0.36 0.39 Pv = (V/4005)2 Noncircular Ducts Hydraulic diameter Dh = 4A/P, where A = duct area (in.2) and P = perimeter (in.) Ducts having the same hydraulic diameter will have approximately the same fluid resistance at equal velocities Fittings Resistance to flow through fittings can be expressed by fitting loss coefficients C The friction loss in a fitting in inches of water is CPv The more radically the airflow is changed in direction or velocity, the greater the fitting loss coefficient See ASHRAE Duct Fitting Database for a complete list 90° mitered elbows with vanes will usually have C between 0.11 and 0.33 Round Flexible Ducts Nonmetallic flexible ducts fully extended have friction losses approximately three times that of galvanized steel ducts This rises rapidly for unextended ducts by a correction factor of if 70% extended, if 80% extended, and if 90% extended For centerline bend radius ratio to diameter of to the approximate loss coefficient is between 0.82 and 0.87 further reprodu 2013PocketGuides.book Page 318 Tuesday, October 7, 2014 3:11 PM © 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 General Heat Pipes A heat pipe heat exchanger looks like a finned tube coil, but the tubes are not interconnected and it is divided into evaporator and condenser sections Warm air passes over evaporator section and cold air over condenser Each tube has a capillary wick, is evacuated, filled with a refrigerant, and sealed A vapor pressure gradient drives the vapor to the condenser end of the tube, where it is revaporized, completing the cycle, as long as there is a temperature difference A wraparound heat pipe removes sensible heat from entering air and transfers it to leaving air A duct-to-duct or slidein heat pipe has one section in the supply air duct and the other in the return duct In both configurations air is precooled before entering the system’s cooling coil Figure 26.8 Dehumidification Enhancement with Wraparound Heat Pipe (Kittler 1996) [2012S, Ch 25, Fig 13] Figure 26.9 Heat Pipe Operation [2012S, Ch 26, Fig 17] 318 further reprodu 2013PocketGuides.book Page 319 Tuesday, October 7, 2014 3:11 PM © 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 General Figure 26.10 Heat Pipe Exchanger Effectiveness (Ratio of temperature drop of precooled air to difference between the entering air and evaporative refrigerant.) [2012S, Ch 26, Fig 18] Figure 26.11 Heat Pipe Assembly [2012S, Ch 26, Fig 16] 319 further reprodu 2013PocketGuides.book Page 320 Tuesday, October 7, 2014 3:11 PM © 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 General Air-to-Air Energy Recovery Recovering sensible heat and/or moisture from an airstream at high temperature or humidity to an airstream at low temperature or humidity can be accomplished by sensible heat exchange devices (heat recovery ventilation, HRVs) or energy or enthalpy devices that transfer both heat and moisture (ERVs) Types include cross-flow air-to-air heat exchangers, rotary wheels, heat pipes, runaround loops, thermosiphons, and turn-tower enthalpy recovery loops Figure 26.12 Fixed-Plate Cross-Flow Heat Exchanger [2012S, Ch 26, Fig 4] Figure 26.13 Variation of Pressure Drop and Effectiveness with Airflow Rates for a Membrane Plate Exchanger [2012S, Ch 26, Fig 4] 320 further reprodu 2013PocketGuides.book Page 321 Tuesday, October 7, 2014 3:11 PM © 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 General Figure 26.14 Coil Energy Recovery Loop [2012S, Ch 26, Fig 14] Figure 26.15 Twin-Tower Enthalpy Recovery Loop [2012S, Ch 26, Fig 25] 321 further reprodu 2013PocketGuides.book Page 322 Tuesday, October 7, 2014 3:11 PM © 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 Table 26.2 Comparison of Air-to-Air Energy Recovery Devices [2012S, Ch 26, Tbl 3] General Fixed Plate Airflow arrangements Membra ne Plate Energy Wheel Heat Wheel Heat Pipe Runaround ThermoCoil Loop siphon Twin Towers Counterflow Counterflow Counterflow Counterflow Counterflow Cross-flow Cross-flow Parallel flow Parallel flow — Counterflow Parallel flow — 50 to 74,000 and up 100 and up 100 and up 100 and up — Equipment size range, cfm 50 and up 50 and up 50 to 74,000 and up Typical sensible effectiveness (ms = me), % 50 to 80 50 to 75 50 to 85 50 to 85 45 to 65 55 to 65 40 to 60 40 to 60 Typical latent effectiveness,* % — 50 to 72 50 to 85 — — — — Total effectiveness,* % — 50 to 73 50 to 85 — — — — — Face velocity, fpm 200 to 1000 200 to 600 500 to 1000 400 to 1000 400 to 800 300 to 600 400 to 800 300 to 450 Pressure drop, in of water 0.4 to 0.4 to 0.4 to 1.2 0.4 to 1.2 0.6 to 0.6 to 0.6 to 0.7 to 1.2 EATR, % to to 0.5 to 10 0.5 to 10 to 0 OACF 0.97 to 1.06 0.97 to 1.06 0.99 to 1.1 to 1.2 0.99 to 1.01 1.0 1.0 1.0 Temperature range, °F –75 to 1470 15 to 120 –40 to 105 –50 to 930 –40 to 105 –40 to 115 –65 to 1470 –65 to 1470 Typical mode of purchase Exchanger Exchanger only only Exchanger in Exchanger in case case Exchanger Exchanger and external and blowers blowers Complete Complete system system Exchanger only Exchanger in case Exchanger and blowers Complete system Exchanger only Exchanger in case Exchanger and blowers Complete system Exchanger only Exchanger in Coil only case Complete Exchanger system and blowers Complete system Exchanger only Complete Exchanger in system case Advantages No moving parts Low pressure drop Easily cleaned Moisture or mass transfer Compact large sizes Low pressure drop Available on all ventilation system platforms Compact large sizes Low pressure drop Easily cleaned No moving parts except tilt Fan location not critical Allowable pressure differential up to psi Exhaust airstream can be separated from supply air Fan location not critical No moving parts Exhaust airstream can be separated from supply air Fan location not critical Latent transfer from remote airstreams Efficient microbiological cleaning of both supply and exhaust airstreams Limitations Supply air Few suppliers may require Long-term some further Large size at Some EATR maintenance cooling or higher flow without and perforheating rates purge mance Some EATR unknown without purge Effectiveness limited by pressure drop and cost Few suppliers Predicting performance requires accurate simulation model Effectiveness may be limited by pressure drop and cost Few suppliers Few suppliers Maintenance and performance unknown No moving parts Low pressure drop Low air leakage Bypass Bypass Bypass Heat rate control dampers and dampers and dampers and (HRC) methods wheel speed ducting ducting control Bypass dampers and wheel speed control Control valve Tilt angle Bypass valve Control valve or pump down to 10% or pump over full speed control of maximum speed control range over full heat rate range *Rated effectiveness values are for balanced flow conditions Effectiveness values increase slightly if flow rates of either or both airstreams are higher than flow rates at which testing is done EATR = Exhaust Air Transfer Ratio OACF = Outdoor Air Correction Factor 322 further reprodu 2013PocketGuides.book Page 323 Tuesday, October 7, 2014 3:11 PM © 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 Panel Heating and Cooling ta = AUST = Typical panels, floor, or ceiling have hydronic tubes or electric cables embedded in, attached to or integral with the floor or ceiling Surface temperature of floor panels should not exceed 84°Ffor comfort; and surface temperature of ceiling panels should not be lower than 1°F above design air dew-point temperature to avoid condensation Panel cooling is usually a supplement to cooling and dehumidification by an air supply system General air temperature in conditioned space, °F average unheated (uncooled) temperature of surfaces directly exposed to the panel; typically 1°F higher than ta in cooling; 2°F lower than ta in heating Typical design ta = 68°F in heating, 76°F in cooling In Figure 26-17: = panel surface temperature, °F tw = average heating (cooling) fluid temperature, °F (for electric systems = skin temperature of cable) qu = heat flux up, Btu/h·ft2 qd = heat flux down, Btu/h·ft2 M = tube (cable) spacing, ft ru = characteristic (combined) panel thermal resistance, ft2 ·h·°F/Btu·ft rc = thermal resistance of panel surface covers such as carpet rp = thermal resistance of panel body rt = thermal resistance of tube wall per unit tube spacing rs = thermal resistance between tube (electric cable) and panel body per unit spacing between tubes (cables); negligible if embedded ru = rtM + rsM + rp + rc For copper tubes secured to aluminum ceiling panels ru = 0.25 M (approximately) Figure 26.16 Primary/Secondary Water Distribution System with Mixing Control [2012S, Ch 6, Fig 11] 323 further reprodu 2013PocketGuides.book Page 324 Tuesday, October 7, 2014 3:11 PM General © 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 Figure 26.17 Design Graph for Sensible Heating and Cooling with Floor and Ceiling Panels [2012S, Ch 6, Fig 9] 324 further reprodu 2013PocketGuides.book Page 325 Tuesday, October 7, 2014 3:11 PM © 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 Variable Refrigerant Flow General Variable-refrigerant-flow (VRF) HVAC systems are a direct-expansion (DX) heat pump technology platform built on the standard reverse Rankine vapor compression cycle These systems are thermodynamically similar to unitary and other common DX systems, and share many of the same components (i.e., compressor, expansion device, and heat exchangers) VRF systems transport heat between an outdoor condensing unit and a network of indoor units located near or within the conditioned space through refrigerant piping installed in the building Attributes that distinguish VRF from other DX system types are multiple indoor units connected to a common outdoor unit (single or combined modules), scalability, variable capacity, distributed control, and simultaneous heating and cooling VRF systems are highly engineered, with single or multiple compressors, multiple indoor units (ducted and nonducted types), and oil and refrigerant management and control components VRF provides flexibility by allowing for many different indoor units (with different capacities and configurations), individual zone control, and the unique ability to offer simultaneous heating and cooling in separate zones on a common refrigerant circuit, and heat recovery from one zone to another Typical capacities range from 18,000 to 760,000 Btu/h for outdoor units and from 5000 to 120,000 Btu/h for indoor units Many VRF systems are equipped with at least one variable-speed and/or variable-capacity compressor; the compressor varies its speed to operate only at the levels necessary to maintain indoor environments to the specified requirements System Types There are three basic types of VRF systems: cooling only (Figure 26.18), heat pump, and heat recovery (Figures 26.19 and 26.20) Heat pumps are air-conditioning systems capable of reversing the direction of the refrigerant flow to provide heating or cooling to the indoor space All indoor units connected to a heat pump system can use individual control and set points, but they operate in the same mode of either heating or cooling at any given time Heat recovery units are heat pump systems that can provide simultaneous heating and cooling All indoor units connected to a heat recovery system not only can use individual control and set points, but they can also individually operate in heating or cooling mode at any given time To match the building’s load profiles, energy is transferred from one indoor space to another through the refrigerant line, and only one energy source is necessary to provide both heating and cooling VRF systems also operate efficiently at part load because of the compressor’s variable capacity control The following definitions are based on AHRI Standard 1230 A heat pump multisplit system is an encased, factory-made, permanently installed assembly that takes heat from a heat source and delivers it to the conditioned space when heating is desired It may remove heat from the conditioned space and discharge it to a heat sink if cooling and dehumidification are desired from the same equipment Normal components include multiple indoor Figure 26.18 Cooling-Only Heat Pump VRF System [2012S, Ch 18, Fig 2] 325 further reprodu 2013PocketGuides.book Page 326 Tuesday, October 7, 2014 3:11 PM General © 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 Figure 26.19 Figure 26.20 Two-Pipe Heat Recovery VRF System [2012S, Ch 18, Fig 3] Three-Pipe Heat Recovery VRF System Examples [2012S, Ch 18, Fig 4] 326 further reprodu 2013PocketGuides.book Page 327 Tuesday, October 7, 2014 3:11 PM © 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 General conditioning coils, compressor(s), and outdoor coil(s) Equipment may be provided in multiple assemblies, intended for use together Other functions may include cleaning, circulating, and humidifying the air A VRF multisplit system is a split-system air conditioner or heat pump with a single refrigerant circuit, one or more outdoor units, at least one variable-speed compressor or other compressor combination that can vary system capacity by three or more steps, and multiple indoor fan-coil units that are individually metered and individually controlled by an integrated control device and common communications network A VRF heat recovery multisplit system operates as an air conditioner or as a heat pump, and also can provide simultaneous heating and cooling operation by transferring recovered energy from the indoor units operating in one mode to other indoor units operating in the other mode Variable refrigerant flow implies three or more steps of control on common, interconnecting piping Safety Considerations for Refrigerants As with any HVAC equipment, VRF systems must include design and application safeguards that protect occupants ASHRAE Standard 15 applies to the design, construction, testing, installation, operation, and inspection of mechanical refrigeration systems This standard specifies safe design, construction, installation, and operation of refrigeration systems Many national, state, and local building codes require compliance with Standard 15 or with similar requirements Designers also need to refer to ASHRAE Standard 34, which lists the most current information related to refrigerant designations, safety classifications, and refrigerant concentration limits (RCL) ASHRAE Standard 34 refers to common names of refrigerants used in HVAC systems, instead of using the chemical name, formula, or trade name The standard establishes a uniform system for assigning reference numbers and safety classifications to refrigerants (including blends) To successfully apply ASHRAE Standard 15 to a project, the designer must know the following: • • • • • Classification and RCL of the refrigerant used Classification of occupancy type in which the indoor unit and/or piping will be located Total amount of refrigerant used in the system Individual occupied zone(s) geometry and connected zones, if applicable Methodology to calculate the maximum amount of refrigerant that can be safely dispersed into a specific zone The smallest space in which any of the indoor units or piping could be located must be capable of safely dispersing the refrigerant charge of the entire VRF system in the unlikely event of a catastrophic leak or failure Examples of spaces that may require additional consideration include • Bathrooms • Electrical rooms • Closets • Small offices • Egress Several options are available to manage smaller spaces; however, care is needed not to violate other local or national codes such as NFPA Standard 70 Options available to manage smaller spaces where the RCL would otherwise be exceeded include the following: • Do not install an indoor unit, but allow the code-required ventilation to maintain conditions in the space • If cooling is required in the occupied space, one option is to increase the actual space volume by providing a permanent opening or connecting to an adjacent room, as described in ASHRAE Standard 15 A permanent opening can be included along the common wall between an electrical room and janitor closet to increase the size of the space; alternatively, install the ceiling high enough to provide the necessary volume, or omit the ceiling entirely • A ducted indoor unit could serve several smaller offices, thus increasing the overall occupied space served by the system • Central VRF systems can be subdivided into a series of smaller systems so that the total charge in a given system does not exceed the RCL limitations for a given space In summary, meeting ASHRAE Standard 15 requirements may only need simple adjustments to the project’s design: carefully considering the building’s zones, determining connected spaces, and optimally placing the piping and indoor units With sound engineering practices, a VRF system can be designed to comply with Standard 15 and all other applicable code requirements 327 further reprodu 2013PocketGuides.book Page 328 Tuesday, October 7, 2014 3:11 PM © 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 Units and Conversions Table 26.3 Conversions to I-P and SI Units [2013F, Ch 38, Tbl 1] General (Multiply I-P values by conversion factors to obtain SI; divide SI values by conversion factors to obtain I-P) Multiply I-P By To Obtain SI acre (43,560 ft2) atmosphere (standard) bar barrel (42 U.S gal, petroleum) Btu (International Table) Btu (thermochemical) Btu/ft2 (International Table) Btu/ft3 (International Table) Btu/gal Btu·ft/h·ft2 · °F Btu·in/h·ft2 · °F (thermal conductivity k) Btu/h Btu/h·ft2 Btu/h·ft2 · °F (overall heat transfer coefficient U) Btu/lb Btu/lb·°F (specific heat cp) bushel (dry, U.S.) calorie (thermochemical) centipoise (dynamic viscosity ) centistokes (kinematic viscosity ) clo dyne dyne/cm2 EDR hot water (150 Btu/h) EDR steam (240 Btu/h) EER ft ft/min, fpm ft/s, fps ft of water ft of water per 100 ft pipe ft2 ft2 ·h· °F/Btu (thermal resistance R) ft2/s (kinematic viscosity ) ft3 ft3/min, cfm ft3/s, cfs ft·lbf (torque or moment) ft·lbf (work) ft·lbf /lb (specific energy) ft·lbf /min (power) footcandle gallon (U.S., *231 in3) gph gpm gpm/ft2 gpm/ton refrigeration grain (1/7000 lb) gr/gal gr/lb horsepower (boiler) (33,470 Btu/h) horsepower (550 ft·lbf /s) inch in of mercury (60°F) in of water (60°F) in/100 ft, thermal expansion coefficient 0.4047 4046.873 *101.325 *100 159.0 0.1580987 1055.056 1054.350 11,356.53 37,258.951 278,717.1765 1.730735 0.1442279 0.2930711 3.154591 5.678263 *2.326 *4.1868 0.0352394 *4.184 *1.00 *1.00 0.155 1.0  10–5 *0.100 43.9606 70.33706 0.293 *0.3048 *304.8 *0.00508 *0.3048 2989 98.1 0.092903 0.176110 92,900 28.316846 0.02832 0.471947 28.316845 1.355818 1.356 2.99 0.0226 10.76391 3.785412 1.05 0.0631 0.6791 0.0179 0.0648 17.1 0.143 9.81 0.7457 *25.4 3.3864 248.84 0.833 m2 kPa kPa L m3 J J J/m2 J/m3 J/m3 W/(m·K) W/(m·K) W W/m2 W/(m2 ·K) kJ/kg kJ/(kg·K) m3 J mPa·s mm2/s (m2 ·K)/W N Pa W W COP m mm m/s m/s Pa Pa/m m2 (m2 ·K)/W mm2/s L m3 L/s L/s N·m J J/kg W lx L mL/s L/s L/(s·m2) mL/J g g/m3 g/kg kW kW mm kPa Pa mm/m 328 further reprodu 2013PocketGuides.book Page 329 Tuesday, October 7, 2014 3:11 PM © 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 Table 26.3 Conversions to I-P and SI Units [2013F, Ch 38, Tbl 1] (Continued) (Multiply I-P values by conversion factors to obtain SI; divide SI values by conversion factors to obtain I-P) By in·lbf (torque or moment) in2 in3 (volume) in3/min (SCIM) in3 (section modulus) in4 (section moment) kWh kW/1000 cfm kilopond (kg force) kip (1000 lbf) kip/in2 (ksi) litre met micron (m) of mercury (60°F) mile mile, nautical mile per hour (mph) millibar mm of mercury (60°F) mm of water (60°F) ounce (mass, avoirdupois) ounce (force or thrust) ounce (liquid, U.S.) ounce inch (torque, moment) ounce (avoirdupois) per gallon perm (permeance at 32°F) perm inch (permeability at 32°F) pint (liquid, U.S.) pound lb (avoirdupois, mass) lbf (force or thrust) lbf /ft (uniform load) lb/ft·h (dynamic viscosity ) lb/ft·s (dynamic viscosity ) lbf ·s/ft2 (dynamic viscosity ) lb/h lb/min lb/h [steam at 212°F (100°C)] lbf /ft2 lb/ft2 lb/ft3 (density ) lb/gallon ppm (by mass) psi quad (1015 Btu) quart (liquid, U.S.) square (100 ft2) tablespoon (approximately) teaspoon (approximately) therm (U.S.) ton, long (2240 lb) ton, short (2000 lb) ton, refrigeration (12,000 Btu/h) torr (1 mm Hg at 0°C) watt per square foot yd yd2 yd3 113 645.16 16.3874 0.273117 16,387 416,231 *3.60 2.118880 9.81 4.45 6.895 *0.001 58.15 133 1.609 *1.852 1.609344 0.447 *0.100 0.133 9.80 28.35 0.278 29.6 7.06 7.489152 5.72135  10–11 1.45362  10–12 4.73176  10–4 To Obtain SI mN·m mm2 mL mL/s mm3 mm4 MJ kJ/m3 N kN MPa m3 W/m2 mPa km km km/h m/s kPa kPa Pa g N mL mN·m kg/m3 kg/(Pa·s·m2) kg/(Pa·s·m) m3 0.453592 453.592 4.448222 14.59390 0.4134 1490 47.88026 0.000126 0.007559 0.2843 47.9 4.88 16.0 120 *1.00 6.895 1.055 0.9463 9.2903 15 105.5 1.016046 0.907184 3.517 133 10.76 *0.9144 0.8361 0.7646 kg g N N/m mPa·s mPa·s Pa·s kg/s kg/s kW Pa kg/m2 kg/m3 kg/m3 mg/kg kPa EJ L m2 mL mL MJ Mg Mg; t (tonne) kW Pa W/m2 m m2 m3 General Multiply I-P *Conversion factor is exact Notes: Units are U.S values unless noted otherwise Litre is a special name for the cubic decimetre L = dm3 and mL = cm3 329 further reprodu 2013PocketGuides.book Page 330 Tuesday, October 7, 2014 3:11 PM © 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 INDEX air air-conditioning formulas 308 air-conditioning processes 16 contaminants 36–37 density 19 enthalpy 18 filters 37–39 friction chart psychrometric chart 15 air quality standards 36 air conditioning cooling load check figures 172 CLTD values 171, 185–88 glass, sunlit 189 shading coefficients 190 air diffusion ADPI 29–30 fully stratified systems 31–32 jet behavior 22–24 mixed-air systems 26–28 outlet performance 26–28, 34 partially mixed systems 33 return air design 35 air quality clean spaces 55 pollutant sources 40 standards 36 ventilation rate 208 air spaces attics 178 emittances 176 thermal resistance 176 air-to-air energy recovery 316–18 ammonia line capacities 152–53 thermodynamic properties 121 ASHRAE Standard 62.1-2010 209–23 ASHRAE Standard 62.2-2010 208 combined heat and power 240 combustion turbines 246 comfort air speed 294 clothing insulation 295 local discomfort 295–96 operative temperature 293 conductivity building materials 179–84 insulation 179 soils 299–300 contaminants air quality standards 36 sources 40 controls systems and terminals 284–92 conversion factors 324–25 cooling load 170, 173 cooling tower 285, 310 costs life cycle 256 maintenance 253–54 owning and operating 255 desiccant cycle 234 equipment 235–39 diffusion 20 duct circular equivalents 6–7 component velocities friction chart velocities vs velocity pressures electrical formulas 231 energy efficiency standards 228 system design 227 engines fuels 251–52 heat balance 243 maintenance 241 sizing 241 waste heat 243–44 equipment costs 255 noise from 265 evaporative cooling 279 exhaust ventilation capture velocities 47 hoods 50–54 transport velocities 49 fans fan laws 10–11 fan noise 266 types 12–13 filters design velocity electronic 37 installation 37 standards 37–39 fittings, for HVAC applications 89–90 formulas air conditioning 308 electrical 231 water 57 water flow for heating/cooling 309 friction chart air water 66–68 fuel cells 247–48 fuel oil data 252 gas pipe sizing 249 glass conductivity 147 shading, coefficients 190 solar heat gain 191–207 glycols, freezing point of 63 330 further reprodu 2013PocketGuides.book Page 331 Tuesday, October 7, 2014 3:11 PM © 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 heat gains laboratory equipment 202–203 lighting 192–94 motors, electric 195–96 office equipment 204–207 people 191 restaurant equipment 197–201 heat pipes 314–15 heat transmission coefficients air space 175 building materials 179–83 fenestration 174 insulation 179 surface conductances 176 hoods kitchen ventilation 51–53 laboratory 54 insulation spaces 175 thermal values for 179 louvers motors characteristics 230 full-load amperes 231 heat gain from 195–96 panel heating and cooling 319 photovoltaic systems 233 piping applications 89 copper 66 expansion, thermal 91 friction loss, water 66–68 fuel oil 252 gas 249 plastic 67 refrigerant capacities 136–47, 152 steam capacity 78–79 steel 68 volume of water in 65 psychrometric chart 15 pump affinity laws 57 net positive suction head 59 power 309 terms 57 typical curves 61 refrigerants line capacities R-134a 146–47 R-22 144–45 R-404A 136–137 R-407C 142–43 R-410A 140–41 R-507A 138–39 R-717 (ammonia) 152, 153 thermodynamic properties R-123 116 R-1234yf 131 R-1234ze(E) 133 R-134a 118–19 R-22 113–14 R-404A 123 R-407C 125 R-410A 127 R-507A 129 R-717 (ammonia) 121 refrigerated display fixtures 207 refrigeration cycle 106 refrigeration load 165–68, 174 refrigerant safety 155 service water heating 93 soils thermal properties 299 solar energy 101–105 sound equipment noise 266 fan noise 266 HVAC acceptable 261 pressure 258–59 rating methods 262–63 NC curves 262 RC curves 263 space air diffusion 20–21 steam flow rate for heating/cooling 77 pipe capacities 78–79 pressure-enthalpy diagram 76 properties 75 sustainability 227 system design criteria 304–307 tanks, cylindrical capacity of horizontal 64 volume 64 thermal storage 311 turbines combustion 246 steam 245 ultraviolet lamp systems 45–46 variable refrigerant flow 321 variable-speed drives 232 ventilation requirements 208–223 vibration 267 vibration isolators 268–278 water demand, hot 96 fixture and demand 97 mass flow vs temperature 63 pipe sizing 309 pumps 57–61 specific heat 63 viscosity 62 volume in pipe 65 331 further reprodu 2013PocketGuides.book Page 332 Tuesday, October 7, 2014 3:11 PM © 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 further reprodu ... entire risk of the use of any information in this publication is assumed by the user Library of Congress Cataloging-in-Publication Data ASHRAE pocket guide for air conditioning, heating, ventilation,... SI Units and Air- Conditioning Formulas 308 Sizing Formulas for Heating/Cooling 309 Cooling Tower Performance 310 Thermal Storage 311–12 Cold -Air Distribution... Chapter ASHRAE Standard ASHRAE Handbook—Fundamentals ASHRAE Handbook—HVAC Systems and Equipment ASHRAE Handbook—HVAC Applications ASHRAE Handbook—Refrigeration viii further reprodu 2013PocketGuides.book