1999 ASHRAE Handbook Preface

9781883413712, 1883413710

Table of contents :
Cover……Page 1
Preface……Page 2
Fig. 1 Typical Residential Installation of Heating, Cooling, Humidifying, and Air Filtering System……Page 3
Heat Pumps……Page 4
Solar Heating……Page 5
Humidifiers……Page 6
Hydronic Central Systems……Page 7
Fig. 3 Typical Installation of Heating and Cooling Equipment for a Manufactured Home……Page 8
References……Page 9
Design Considerations……Page 10
Load Determination……Page 11
Design Considerations……Page 12
Fig. 3 Air Mixing Using Fans Behind Cases……Page 13
Table 2 Approximate Occupancy for Department Stores……Page 14
Design Considerations……Page 15
Design Considerations……Page 16
Load Characteristics……Page 17
Table 1 General Design Criteriaa, b……Page 18
Table 1 General Design Criteriaa, b (Concluded)……Page 19
Load Characteristics……Page 20
Special Considerations……Page 21
Design Concepts……Page 22
Spatial Requirements……Page 23
Special Considerations……Page 24
Transportation Centers……Page 25
Special Considerations……Page 26
References……Page 27
Noise and Vibration Control……Page 28
Air Distribution……Page 29
Legitimate Theaters……Page 30
Ancillary Spaces……Page 31
Environmental Control……Page 32
Ventilation Requirements……Page 33
Fairs and Other Temporary Exhibits……Page 34
Bibliography……Page 35
Energy-Efficient Systems……Page 36
Total Energy Systems……Page 37
Table 1 Hotel Classes……Page 38
Table 2 Hotel Design Criteriaa,b……Page 39
Fig. 2 Alternate Location for Hotel Guest Room Air Conditioning Unit on Room Perimeter and Chase………Page 40
Table 3 Design Criteria for Hotel Back-of-the-House Areasa……Page 41
Table 4 Design Criteria for Hotel Guest Room Makeup Air Units……Page 42
Bibliography……Page 43
Energy Considerations……Page 44
Preschools……Page 45
Colleges and Universities……Page 46
Variable Air Volume……Page 47
References……Page 48
Air Conditioning in the Prevention and Treatment of Disease……Page 49
Air Quality……Page 50
Table 2 Influence of Bedmaking on Airborne Bacterial Count in Hospitals……Page 51
Smoke Control……Page 52
Table 3 General Pressure Relationships and Ventilation of Certain Hospital Areas……Page 53
Surgery and Critical Care……Page 54
Ancillary……Page 55
Service……Page 57
Insulation……Page 58
Continuity of Service and Energy Concepts……Page 59
Applicability of Systems……Page 60
Bibliography……Page 61
Air Conditioning……Page 62
Other Concerns……Page 63
Condensers……Page 64
Receiver-Drier Assembly……Page 65
Fig. 4 Clutch Cycling System with Thermostatic Expansion Valve (TXV)……Page 66
Bus Air Conditioning……Page 67
Inlets and Outlets……Page 68
Fig. 10 Typical Arrangement of Air-Conditioning in an Interurban Bus……Page 0
Vehicle Types……Page 69
Interior Comfort……Page 70
Refrigeration Components……Page 71
Bibliography……Page 72
Cabin Ozone Concentration……Page 73
ECS Performance……Page 74
Fig. 3 Variation of Ambient Pressure with Altitude……Page 75
Pneumatic System……Page 76
Air Conditioning……Page 77
Cabin Pressure Control……Page 78
Ozone Protection……Page 79
Air Distribution……Page 80
Microbial Aerosols……Page 81
References……Page 82
Ventilation Requirements……Page 83
Heating Coils……Page 84
Fig. 2 Multizone Central (Type C) System……Page 85
High-Velocity Dual-Duct System……Page 86
Control……Page 87
Heating Coils……Page 88
References……Page 89
Rates of Chemical Reactions……Page 90
Table 1 Temperatures and Humidities for Industrial Air Conditioning……Page 91
Static Electricity……Page 92
Thermal Control Levels……Page 93
Table 3 Facilities Checklist……Page 94
Floor Heating……Page 95
Cooling Systems……Page 96
Contaminant Control……Page 97
Bibliography……Page 98
Natural Ventilation……Page 99
Mechanical Ventilation……Page 100
Fig. 2 Longitudinal Ventilation……Page 101
Ventilation System Enhancements……Page 102
Emergency Ventilation Air Quantities……Page 103
Straight Ducts……Page 104
Design Considerations……Page 105
Table 4 Average Entrance and Exit Times for Vehicles……Page 106
CO Demand Ventilation Control……Page 107
Other Considerations……Page 108
Storage Areas……Page 109
Bus Terminals……Page 110
Table 6 Approximate Diesel Bus Engine Emissions (ppm)……Page 111
Control by Contaminant Level Monitoring……Page 112
Mechanical Ventilation……Page 113
Fig. 14 Tunnel Ventilation Concept……Page 114
Fig. 16 Emergency Ventilation Concept……Page 115
Measures to Limit Heat Loads……Page 116
Design Concepts……Page 117
Fig. 18 Railroad Tunnel Aerodynamic Related Variables……Page 118
Maintenance and Repair Areas……Page 119
Table 7 Typical Diesel Locomotive Emission Data……Page 120
Fan Design and Operation……Page 121
Damper Design……Page 122
Damper Applications and Types……Page 123
Exhaust Outlets……Page 124
Bibliography……Page 125
Hazard Assessment……Page 126
Architectural Considerations……Page 127
Types of Fume Hoods……Page 128
Fume Hood Performance……Page 129
Fig. 2 Types of Biological Safety Cabinets……Page 131
Biological Safety Cabinets……Page 130
Laminar Flow Clean Benches……Page 132
Noise……Page 133
Types of Exhaust Systems……Page 134
Materials and Construction……Page 135
Constant Air Volume (CAV) Versus Variable Air Volume (VAV) Room Airflow Control……Page 136
Stack/Intake Separation……Page 137
Table 1 Recommended Dry-Bulb Temperatures for Common Laboratory Animals (ILAR 1996)……Page 138
Biosafety Level 1……Page 139
Teaching Laboratories……Page 140
Energy Conservation……Page 141
Economics……Page 142
Bibliography……Page 143
Engine Exhaust……Page 145
Test Cell Supply……Page 146
Ventilation……Page 147
Bibliography……Page 148
Fig. 1 ISO Air Cleanliness Class Limits……Page 149
Particle Sources in Clean Spaces……Page 150
Fig. 3 ISO Class 7 Nonunidirectional Cleanroom with HEPA Filters Located in Supply Duct and ISO ………Page 151
Testing Clean Air and Clean Spaces……Page 152
Pharmaceutical and Biomanufacturing Clean Spaces……Page 153
Design Concerns for Pharmaceutical Cleanrooms……Page 154
Maintainability……Page 155
Qualification Plan and Acceptance Criteria……Page 156
Fig. 9 Elements of a Clean Tunnel……Page 157
Air-Handling……Page 158
Process Exhaust……Page 159
Sizing and Redundancy……Page 160
Construction Finishes……Page 161
Bibliography……Page 162
Room Environmental Requirements……Page 163
Air-Conditioning Systems……Page 164
Fig. 3 Air-Handling Unit with Return Air Bypass……Page 165
Ceiling and Ceiling Plenum Supply……Page 166
Chilled Water Distribution Systems……Page 167
Bibliography……Page 168
Fig. 1 Work Flow Through a Printing Plant……Page 169
Platemaking……Page 170
Recommended Environment……Page 171
Air Filtration……Page 172
References……Page 173
Cotton System……Page 174
Table 1 Recommended Humidities for Wool Processing at 24 to 27C……Page 175
Dyeing and Finishing……Page 176
Air Distribution……Page 177
Fig. 3 Central Collector for Carding Machine……Page 178
Bibliography……Page 179
Fig. 1 Open Machine Ventilation……Page 180
Processing Temperature Control……Page 181
Long-Term Storage……Page 182
Bibliography……Page 183
Derivation of Collection Requirements……Page 184
Fig. 2 Time Required for Visible Mold Growth……Page 185
Role of Fluctuations and Low Temperature……Page 186
Fig. 5 Interaction of Air Leakage, Wood Coating, and Textile Buffering on Response of Chest of D………Page 187
Specifications Apply to Entire Usable Space……Page 188
Building Envelope Problem……Page 189
Envelope Design……Page 190
Design Issues……Page 191
Primary Elements and Features……Page 192
Fig. 7 Primary Elements of Preservation Environment HVAC System……Page 193
Types of Systems……Page 194
References……Page 195
Temperature Control……Page 197
Air Quality Control……Page 198
Degree of Shelter……Page 199
Supplemental Heating……Page 200
Natural Ventilation……Page 201
Fans……Page 202
Swine……Page 203
Poultry……Page 204
Laboratory Animals……Page 205
Site Selection……Page 206
Table 4 Suggested Design Air Changes (N)……Page 207
Fig. 9 Temperature Profiles in a Greenhouse Heated with Radiation Piping along the Sidewalls……Page 208
Evaporative Cooling……Page 209
Carbon Dioxide Enrichment……Page 210
Photoperiod Control……Page 211
Plant Growth Environmental Facilities……Page 212
Heating, Air Conditioning, and Airflow……Page 213
Table 12 Approximate Mounting Height and Spacing of Luminaires in Greenhouses……Page 214
Table 13 Height and Spacing of Luminaires……Page 215
Table 14 Mounting Height for Luminaires in Storage Areas……Page 216
Bibliography……Page 217
Table 1 Approximate Allowable Storage Time (Days) for Cereal Grains……Page 221
Fans……Page 222
Fig. 2 Rack-Type Continuous-Flow Grain Dryer with Alternate Rows of Air Inlet and Outlet Ducts……Page 223
Deep-Bed Drying……Page 224
Fig. 7 Tunnel or Duct Air Distribution System……Page 225
Table 7 Recommended Unheated Air Airflow Rate for Different Grains and Moisture Contents in the………Page 226
Soybeans……Page 227
Cotton……Page 228
Moisture Migration……Page 229
Fig. 13 Aerating to Change Grain Temperature……Page 230
Fig. 15 Duct Arrangements for Large Flat Storages……Page 231
Bibliography……Page 232
Pulp and Paper Operations……Page 233
Fig. 3 Pocket Ventilation……Page 234
System Selection……Page 235
BIBLIOGRAPHY……Page 236
Temperature and Humidity……Page 237
Table 1 Design Criteria for Coal-Fired Power Plant……Page 238
Air Distribution……Page 239
Local Control and Instrumentation Areas……Page 240
Coal- and Ash-Handling Areas……Page 241
Suboperating Level……Page 242
Combustion Turbine Areas……Page 243
Ventilation of Conveyor and Crusher Motors in a Coal Dust Environment……Page 244
References……Page 245
Bibliography……Page 246
Safety Design Basis……Page 247
Filtration……Page 248
Differential Pressures……Page 249
Air and Gaseous Effluents Containing Radioactivity……Page 250
Reactor Containment Building……Page 251
Auxiliary Building……Page 252
Glove Boxes……Page 253
Codes and Standards……Page 254
Groundwater……Page 255
Wall Rock Heat Flow……Page 256
Evaporative Cooling of Mine Chilled Water……Page 257
Fig. 4 Underground Heat Exchanger, Pressure Reduction System……Page 258
Fig. 5 Layout for Turbine-Pump-Motor Unit with Air-Cooling Plants and Mechanical Refrigeration……Page 259
Fig. 6 Underground Air-Cooling Plants……Page 260
Bibliography……Page 261
Determining Drying Time……Page 262
Dryer Calculations……Page 263
Conduction Drying……Page 264
Fig. 4 Cross Section and Longitudinal Section of Rotary Dryer……Page 265
Fig. 7 Section of Blow-Through-Type Continuous Dryer……Page 266
References……Page 267
Ventilation for Heat Relief……Page 268
Heat Stress—Thermal Standards……Page 269
Local Discomfort and Individual Parameters……Page 270
Fig. 2 Optimal and Acceptable Ranges of Air Temperature and Air Speed in Occupied Zone for Diffe………Page 271
Fluid Dynamic Modeling……Page 273
Field Testing……Page 272
Computer Modeling……Page 274
Quantity of Supplied Air……Page 275
Air Supply Methods……Page 276
Fig. 4 Concentrated Air Supply Methods……Page 277
Bibliography……Page 409
Guidelines for Selecting an Air Distribution Method……Page 278
Fig. 8 Air Supply Through Perforated Ducts, Ceilings, and Panels……Page 279
Fig. 11 Spiral Vortex Ventilation System……Page 280
Air Distribution Design in Industrial Spaces……Page 281
Table 7 Typical Air Diffusers and Their Applications……Page 282
Locker Room, Toilet, and Shower Space Ventilation……Page 283
Table 10 Coefficients Kt and Kw of Natural Ventilation Effectiveness for Industrial Spaces with ………Page 284
Air Curtains……Page 285
Principles of Air Curtain Design……Page 286
Roof Ventilators……Page 287
References……Page 288
Bibliography……Page 290
System Classification……Page 292
Fig. 3 Hoods Attached to Flexible Fume Extraction Arms……Page 293
Table 1 Range of Capture (Control) Velocities……Page 294
Theoretical Considerations……Page 295
Table 2 Centerline Air Velocities Induced by Nonenclosing Hoods……Page 296
Air and Contaminant Distribution with Nonbuoyant Sources……Page 297
Fig. 13 Thermal Plume above Heat Source……Page 298
Pressure Losses in Local Exhausts……Page 299
Fig. 16 Multislot Nonenclosing Hood……Page 300
Overhead Hoods……Page 301
Fig. 19 Ap for Various Situations……Page 302
Fig. 23 Schematics of Sidedraft Slot Hood on Tank……Page 303
Fig. 25 K1 Coefficient Evaluation for Downdraft Hoods……Page 304
Design Procedure……Page 305
Fig. 29 Push-Pull Hood over Welding Robot……Page 306
Table 5 Contaminant Transport Velocities……Page 307
Fig. 30 Push-Pull Protection System……Page 308
Air-Moving Devices……Page 309
References……Page 310
Bibliography……Page 311
Exhaust Hoods……Page 313
Type I Hoods—Grease Removal……Page 314
Table 2 Typical Model Code Exhaust Flow Rates for Conventional Type I Hoods……Page 315
Fig. 1 Styles of Commercial Kitchen Exhaust Hoods……Page 316
Fig. 2 Internal Methods of Introducing Replacement Air……Page 317
Exhaust Systems……Page 318
Types of Exhaust Fans……Page 319
Replacement (Makeup) Air Systems……Page 320
Principles……Page 321
Multiple-Hood Systems……Page 322
Energy Considerations……Page 323
Fire Suppression……Page 324
Preventing Fire Spread……Page 326
Maintenance……Page 327
Control Systems (Operation and Safety)……Page 328
Replacement (Makeup) Air……Page 329
Bibliography……Page 330
Temperature……Page 333
Table 1 Representative Fluid Composition from Geothermal Wells in Various Resource Areas……Page 334
Well Flow Rate……Page 335
Terminology……Page 336
Flow Testing……Page 337
Table 4 Principle Effects of Key Corrosive Species……Page 338
Fig. 6 Chloride Concentration Required to Produce Localized Corrosion of Stainless Steel as Func………Page 339
Pumps……Page 340
Fig. 7 Plate Heat Exchanger……Page 341
Piping……Page 342
Fig. 9 Heating System Schematic……Page 343
Fig. 11 Closed Geothermal District Heating System……Page 344
Industrial Applications……Page 345
Fig. 13 Vertical Closed-Loop Ground-Coupled Heat Pump System……Page 346
Surface Water Heat Pumps……Page 347
Vertical Design……Page 348
Table 6 Thermal Properties of Selected Soils, Rocks, and Backfills……Page 349
Fig. 18 Fourier/G-Factor Graph for Ground Thermal Resistance……Page 350
Table 8 Long-Term Change in Ground Field Temperature for 10 by 10 Vertical Grid with a 350 kW Bl………Page 351
Fig. 22 General Layout of a Spiral Earth Coil……Page 352
Well Pumps……Page 353
Indirect Systems……Page 354
Thermal Patterns in Lakes……Page 355
Fig. 27 Closed Loop Lake Coil in Bundles……Page 356
References……Page 357
Bibliography……Page 358
Solar Time……Page 359
Incident Angle……Page 360
Solar Radiation at the Earth’s Surface……Page 361
Design Values of Total Solar Irradiation……Page 362
Longwave Atmospheric Radiation……Page 363
Solar Heat Collection by Flat-Plate Collectors……Page 364
Fig. 9 Various Types of Solar Collectors……Page 365
Concentrating Collectors……Page 366
Collector Performance……Page 367
Fig. 12 Variation of Upward Heat Loss Coefficient UL with Collector Plate Temperature and Ambien………Page 368
Thermosiphon Systems……Page 369
Indirect Water Heating Systems……Page 370
Hot Water Recirculation……Page 371
Fig. 21 DHW Recirculation System with Makeup Preheat……Page 372
Cooling by Nocturnal Radiation and Evaporation……Page 374
Solar Heating and Cooling Systems……Page 375
Space Heating and Service Hot Water……Page 376
Standard Systems……Page 377
Fig. 28 Solar Air Heating System……Page 378
Passive Heating……Page 379
Table 5 Calculations for Example 7……Page 380
Collector Mounting……Page 381
Performance Monitoring/Minimum Instrumentation……Page 382
Uses……Page 383
Photovoltaic Applications……Page 384
References……Page 385
Bibliography……Page 386
Storage Media……Page 387
Economics……Page 388
Operating Modes……Page 389
Control Strategies……Page 390
Refrigeration Design……Page 391
Fig. 2 State Diagram of Cool Storage System……Page 392
Storage of Heat in Cool Storage Units……Page 393
Space Heating……Page 394
Storage in Aquifers……Page 395
Performance of Chilled Water Storage……Page 396
Storage Tank Insulation……Page 397
Internal Melt Ice-on-Coil Storage……Page 398
Ice-Harvesting……Page 399
Fig. 12 Freezing Points of Calcium Magnesium Acetate (CMA) Solutions……Page 400
Circuits for Ice Storage……Page 401
Room Storage Heaters (Room Units)……Page 402
Fig. 19 Pressurized Water Heater……Page 403
Systems……Page 404
Ice-on-Coil Systems (External and Internal Melt)……Page 405
Refrigeration Equipment……Page 406
References……Page 407
Organization……Page 411
Energy Manager……Page 412
Implementing a Program……Page 413
Fig. 3 Actual Demand Versus Billing Demand (85%, 11 Month Ratchet)……Page 414
Table 1 1995 Commercial Building Characteristics……Page 415
Table 2A 1995 Commercial Building Energy Consumption……Page 418
Table 2B 1995 Commercial Building Energy Consumption……Page 419
Table 2A 1995 Commercial Building Energy Consumption (Continued)……Page 420
Table 2B 1995 Commercial Building Energy Consumption (Continued)……Page 421
Table 2A 1995 Commercial Building Energy Consumption (Continued)……Page 422
Table 2B 1995 Commercial Building Energy Consumption (Continued)……Page 423
Energy Audits……Page 424
Table 4 1993 Residential Energy Consumption……Page 425
Fig. 5 Energy Cost Distribution……Page 426
Table 5 Example of Analytical Method for Analyzing Electrical Operating Costs……Page 427
Fig. 7 Potential Energy Conservation Opportunities……Page 428
Implementation of Energy Reductions……Page 429
References……Page 430
Table 1 Owning and Operating Cost Data and Summary……Page 443
Operating Costs……Page 444
Electrical Energy……Page 445
Table 4 Annual HVAC Maintenance Cost Adjustment Factors (in dollars per square metre, 1983 U.S. ………Page 446
Financing Alternatives……Page 447
More Sophisticated Economic Analysis Methods……Page 448
Table 5 Annual Capital Recovery Factors……Page 449
Fig. 1 Capital Recovery Factor Versus Time……Page 450
Table 7 Summary of Cash Flow (for Example 10)……Page 452
Symbols……Page 453
Bibliography……Page 454
Design Considerations……Page 455
Stratification……Page 456
Equipment and System Check……Page 457
Static Control……Page 458
Balancing the VAV System……Page 459
Principles and Procedures for Balancing Hydronic Systems……Page 460
Generalized Chilled Water Terminal— Heat Transfer Versus Flow……Page 461
Sizing Balancing Valves……Page 462
Other Balancing Techniques……Page 463
General Balance Procedures……Page 464
Conversion of Differential Pressure to Head……Page 465
Orifice Plates, Venturi, and Flow Indicators……Page 466
Fig. 12 Differential Pressure Used to Determine Pump Flow……Page 467
Steam Flow Measuring Devices……Page 468
Temperature Control Verification……Page 469
Data Recording……Page 470
Guidelines for Developing a Field Study Form……Page 471
Sound Level Criteria……Page 472
Noise Transmission Problems……Page 473
Instruments……Page 474
Testing Equipment Vibration……Page 475
Vibration Analysis……Page 476
Fig. 18 Bent Shafts……Page 477
Bibliography……Page 478
Quantitative Management Concept……Page 479
Documentation……Page 480
Medium-Complexity Systems……Page 481
Responsibilities……Page 482
Bibliography……Page 483
Hardware……Page 484
Software Options……Page 485
Design Tools……Page 486
Engineering Design Calculations……Page 487
Fig. 1 Example of Duct System Node Designation……Page 488
Piping Design……Page 489
Equipment Selection and Simulation……Page 490
Energy and System Simulation……Page 491
Computer-Aided Design……Page 492
Monitoring and Control……Page 493
Applications of Artificial Intelligence……Page 494
World Wide Web……Page 495
Bibliography……Page 496
Specific Technology Assessment……Page 498
Protocols for Performance Monitoring……Page 499
Commercial Retrofit Monitoring……Page 500
Commercial New Construction Monitoring……Page 501
Steps for Project Design and Implementation……Page 502
Part Three: Specify Data Products and Project Output……Page 503
Part Four: Specify Monitoring Design Approach……Page 504
Part Five: Specify Data Analysis Procedures and Algorithms……Page 505
Part Six: Specify Field Data Monitoring Points……Page 507
Table 7 General Characteristics of Data Acquisition Systems……Page 508
Part Seven: Resolve Data Product Accuracies……Page 509
Part Eight: Specify Verification and Quality Assurance Procedures……Page 510
References……Page 511
Bibliography……Page 512
Subsystems……Page 514
Control and Performance Measures……Page 515
Fig. 3 Steam Preheat Valve Position and Outdoor Air Damper Position……Page 516
Fig. 6 Example Power Contours for Chilled Water and Supply Air Temperatures……Page 517
Fig. 8 Comparison of Free Floating and Fixed Humidity……Page 518
Fig. 9 Comparisons of Optimal Control with Conventional Control Strategies……Page 519
Fig. 11 Heating Energy Consumption of Large Office Building……Page 520
Fig. 13 Example Comparison of One-Speed, Two-Speed, and Variable-Speed Fans for Four Cell Coolin………Page 521
Near-Optimal Tower Fan Sequencing……Page 522
Fig. 16 Trade-offs Between Chiller Power and Fan Power with Tower Airflow……Page 523
Table 3 Parameter Estimates for Near-Optimal Tower Control Equation……Page 524
Summary and Implementation……Page 525
Pump Sequencing……Page 526
Chilled Water Reset with Variable-Speed Pumping……Page 527
Fig. 22 Comparisons of Optimal Chilled Water Temperature……Page 528
Table 4 Parameter Estimates for Near-Optimal Chilled Water Set Point Equation……Page 529
Sequencing and Loading of Multiple Chillers……Page 530
Fig. 25 Effect of Relative Loading for Two Identical Parallel Chillers……Page 531
Order for Bringing Chillers Online and Offline……Page 533
Fig. 26 Chiller COP for Two Chillers……Page 532
Load Conditions for Bringing Chillers Online or Offline……Page 534
Fig. 29 AHU Sequencing Strategy with Multiple Feedback Controllers……Page 535
Recovery from Night Setback or Setup……Page 536
Fig. 31 Total Coil Load for East and West Chiller Units……Page 537
Fig. 32 Schematic of Ice Storage System……Page 538
Discharging Strategies……Page 539
Fig. 33 Flowchart for Rule-Based Controller Discharge Strategy……Page 540
Forecasting Diurnal Energy Requirements……Page 541
A Forecasting Algorithm……Page 542
Fig. 35 Schematic of Modular Optimization Problem……Page 543
Simplified System-Based Optimization Approach……Page 544
Dynamic Optimization……Page 546
Ice Storage Control Optimization……Page 547
References……Page 548
Bibliography……Page 549
Commissioning Authority……Page 550
Program and Predesign Commissioning Phase……Page 551
Design Commissioning Phase……Page 552
Acceptance Commissioning Phase……Page 553
Operations and Maintenance Training Program……Page 554
Post-Acceptance Commissioning……Page 555
Construction……Page 556
Moisture Control……Page 557
Low-Density Construction……Page 558
Moisture……Page 559
Thermal Performance……Page 560
Conduction/Convection and Radiation Effects……Page 561
Face Seal Approach……Page 562
Thermal Bridges in Buildings……Page 563
Thermal Bridge Mitigation……Page 564
Design Recommendations……Page 565
Fig. 11 Mullion Without Exterior Projection……Page 566
References……Page 567
Fig. 1 Flow Recirculation Regions and Exhaust-to-Intake Stretched-String Distances……Page 569
Air Intake Locations to Minimize Contamination……Page 570
Fig. 5 Surface Flow Patterns and Building Dimensions……Page 571
Fig. 6 Design Procedure for Required Stack Height to Avoid Contamination……Page 572
Dilution Prediction Equations……Page 574
Fig. 7 Normalized Concentration Contours for Central Vent on Roof of a Low-Rise Building……Page 575
Symbols……Page 577
References……Page 578
Toxicity……Page 579
Table 1 Major Chemical Families of Gaseous Air Contaminants (with Examples)……Page 580
Table 2 Characteristics of Selected Gaseous Air Contaminants……Page 581
Tobacco Smoke……Page 582
Building Materials and Furnishings……Page 583
Table 7 Primary Ambient Air Quality Standards for the United States……Page 584
Table 8 Typical Outdoor Concentration of Selected Gaseous Air Contaminants……Page 585
Contaminant Load Estimates……Page 586
Local Source Control……Page 587
Dilution Through General Ventilation……Page 588
Control Processes……Page 589
Fig. 3 Dependence of Contaminant Concentration on Bed Depth and Exposure Time……Page 590
Fig. 4 Sectional and Schematic Views of Typical Adsorber and Chemisorber Configurations……Page 591
Media Selection……Page 592
Special Cases……Page 593
Energy Concerns……Page 594
Start-Up and Commissioning……Page 595
Field Testing……Page 596
References……Page 597
Bibliography……Page 599
Fan……Page 600
Fig. 6 Multiple Static Sensors……Page 601
Fig. 9 Airflow Tracking Control……Page 602
Fig. 15 Cooling Tower……Page 603
Heating Coil……Page 604
Humidity Control……Page 605
Outdoor Air Control……Page 606
Terminal Units……Page 607
Fig. 37 Fan-Powered VAV Terminal Unit……Page 608
Air Handling……Page 609
Fig. 45 Cycles I, II, and W Control Arrangements……Page 610
Multizone Dual-Duct Systems……Page 611
Fig. 51 Dual Supply Fan System……Page 612
Fig. 54 Constant Flow Chilled Water System……Page 613
Water Heating……Page 614
Duct Static Pressure Limit Control……Page 615
Control Principles for Energy Conservation……Page 616
Size of Controlled Area……Page 617
References……Page 618
Acoustical Design of HVAC Systems……Page 619
Basic Design Techniques……Page 620
Table 1 Sound Sources, Transmission Paths, and Recommended Noise Reduction Methods……Page 621
Fig. 5 Plenum Fan Sound Profiles……Page 622
Fig. 6 Basis for Fan Selection in VAV Systems……Page 623
Fig. 7 Sound Paths for Typical Rooftop Installations……Page 624
Table 2 Duct Breakout Insertion Loss—Potential Low-Frequency Improvement over Bare Duct and Elbow……Page 625
Table 5 Decibels to Be Added to Diffuser Sound Rating to Allow for Throttling of Volume Damper……Page 626
Fig. 9 Typical Minimum and Maximum ARI-575 Lp Values for Screw Chillers—450 to 1400 kW……Page 627
Fig. 10 Estimated dB Buildup in Mechanical Room for ARI-575 Chiller Sound Levels……Page 628
Fig. 12 Schematic of Plenum Chamber……Page 629
Acoustically Lined Round Sheet Metal Ducts……Page 630
Nonmetallic Insulated Flexible Ducts……Page 631
Fig. 13 Rectangular Duct Elbows……Page 632
Fig. 14 Dissipative Duct Silencers……Page 633
Table 19 Duct End Reflection Loss— Duct Terminated Flush with Wall……Page 634
Fig. 17 Various Outlet Configurations for Centrifugal Fans and Their Possible Rumble Conditions……Page 635
Fig. 22 Duct Breakin……Page 636
Table 22 TLout Versus Frequency for Flat Oval Ducts……Page 637
Table 23 Ceiling/Plenum/Room Attenuations for Generic Ceilings with T-Bar Suspensions……Page 638
Point Sound Sources……Page 639
Sound Rating Methods……Page 640
Fig. 24 NCB Noise Criterion Curves Drawn from ANSI Standard S 12.2……Page 641
Table 33 Definition of Sound-Quality Descriptor and Quality-Assessment Index (QAI) To Aid in Int………Page 642
Table 34 Design Guidelines for HVAC-Related Background Sound in Rooms……Page 643
Fig. 27 Correction for Composite Noise Rating (CNR) Associated with Ambient Noise……Page 644
Mechanical Equipment Room Sound Isolation……Page 645
Special Wall Construction……Page 646
Floating Floors……Page 647
Enclosed Air Cavity……Page 648
Table 41 Compensation Factors for Source Area Effect……Page 649
Sound Barriers……Page 650
Fig. 34 Examples of Surfaces That Can Reflect Sound Around or Over a Barrier Wall……Page 651
Fig. 35 Sound Paths Layout for Example 8……Page 652
Fig. 37 Return Air Portion Layout for Example 7……Page 653
Specification of Vibration Isolators……Page 655
Table 44 Equipment Vibration Criteria……Page 656
Table 45 Selection Guide for Vibration Isolation……Page 657
Resilient Pipe Hangers and Supports……Page 660
Flexible Pipe Connectors……Page 661
Isolating Duct Vibration……Page 662
Noise Problems……Page 663
Vibration Problems……Page 664
References……Page 665
Bibliography……Page 666
Biological Characteristics……Page 667
Factors That Contribute to Corrosion……Page 668
Preventive and Protective Measures……Page 669
Scale Control……Page 670
Control Measures……Page 671
Legionnaires’ Disease……Page 672
Mechanical Filtration……Page 673
Start-Up and Recommissioning for Undrained (Stagnant) Systems……Page 674
Ice Machines……Page 675
Boiler Systems……Page 676
Terminology……Page 677
References……Page 678
Gas-Fired or Oil-Fired……Page 679
Fig. 1 Indirect, External Storage Water Heater……Page 680
Piping Material……Page 681
Table 2 Heat Loss of Pipe at 60C Inlet, 21C Ambient……Page 682
Water Pressure—Commercial Kitchens……Page 683
Water Heating Terminology……Page 684
Fig. 8 Lime Deposited Versus Temperature and Water Use……Page 685
Hot Water from Tanks and Storage Systems……Page 686
Table 5 HUD-FHA Minimum Water Heater Capacities for One- and Two-Family Living Units……Page 687
Table 6 Overall (OVL) and Peak Average Hot Water Use……Page 688
Table 7 Hot Water Demands and Use for Various Types of Buildings……Page 689
Examples……Page 690
Fig. 17 Office Buildings……Page 691
Fig. 21 High Schools……Page 692
Food Service……Page 694
Showers……Page 693
Table 11 General-Purpose Hot Water (60°C) Requirement for Various Kitchens Usesa,b……Page 695
Commercial Laundries……Page 696
Swimming Pools/Health Clubs……Page 697
Fig. 22 Modified Hunter Curve for Calculating Hot Water Flow Rate……Page 698
Boilers for Indirect Water Heating……Page 699
References……Page 700
Bibliography……Page 701
Heat Balance……Page 702
Heat Flux Equations……Page 703
Table 1 Frequencies of Snow-Melting Loadsa……Page 705
Weather Data and Load Calculation Results……Page 704
Annual Operating Data……Page 707
Operating Cost Example……Page 709
Fig. 2 Snow-Melting Loads Required to Provide a Snow-Free Area Ratio of 0 for 99% of the Time……Page 708
Operating Cost……Page 710
Fig. 3 Detail of Hydronic Snow-Melting System……Page 711
Fig. 4 Piping Details for Concrete Construction Jobs……Page 712
Heat Flux……Page 713
Table 6 Mineral Insulated Cold Lead Cables (Maximum Voltage—600 V)……Page 714
Fig. 6 Typical Section, Mineral Insulated Heating Cable in Asphalt……Page 715
Self-Regulating Cable……Page 716
Installation……Page 717
Fig. 9 Typical Power Density Distribution for Infrared Snow-Melting System……Page 718
Bibliography……Page 719
Cooling……Page 720
Air Cleaning……Page 721
Booster Refrigeration……Page 722
Residential or Commercial Cooling……Page 723
Industrial Applications……Page 724
Area Cooling……Page 725
Fig. 8 Arrangements for Cooling Large Motors……Page 726
Cooling Animals……Page 727
Cooling Greenhouses……Page 728
Psychrometrics……Page 729
Entering Air Considerations……Page 730
Bibliography……Page 731
Fire Management……Page 732
Fig. 4 Pressure Difference due to Stack Effect……Page 733
Expansion……Page 734
Dilution Remote from Fire……Page 735
Airflow……Page 736
Flow Areas……Page 737
Fig. 9 Leakage Paths in Series……Page 738
Design Pressure Differences……Page 739
Pressurized Stairwells……Page 740
Stairwell Analysis……Page 741
Fig. 17 Stairwell Pressurization with Bypass Around Supply Fan……Page 742
Computer Analysis for Pressurization Systems……Page 743
Fig. 19 Smoke Exhaust to Maintain Steady Clear Height……Page 744
Atrium Smoke Filling by a Steady Fire……Page 745
Steady Clear Height with Upper Layer Exhaust……Page 746
Prestratification and Detection……Page 747
References……Page 748
Elementary Design Relationships……Page 750
Design Criteria for Acceptable Radiant Heating……Page 751
Fig. 4 ASHRAE Comfort Zones for Sedentary Individuals……Page 752
Geometry of Beam Heating……Page 753
Radiation Patterns……Page 754
Black Globe Thermometer……Page 755
Applications……Page 756
Panel Heating and Cooling……Page 757
References……Page 758
Seismic Restraint Design……Page 759
Table 2 Values of Site Coefficient Fa as Function of Site Class and Mapped Spectral Response Acc………Page 760
Applying Static Analysis Using 1994 UBC……Page 761
Fig. 1 Maximum Considered Earthquake Ground Motion for the United States……Page 762
Fig. 1 Maximum Considered Earthquake Ground Motion for the United States (Continued)……Page 763
Table 6 International Seismic Zones……Page 764
Table 7 Typical Allowable Loads for Wedge-Type Anchors……Page 765
Seismic Snubbers……Page 766
Fig. 5 Equipment Rigidly Mounted to Structure (Example 1)……Page 767
Fig. 6 Equipment Supported by External Spring Mounts……Page 768
Fig. 8 Equipment with Different Center of Mass than Isolator Group (in Plan View)……Page 769
Fig. 9 Supports and Bracing for Suspended Equipment……Page 770
Table 10 Definition of Exposure Categories……Page 771
Table 13 Exposure Category Constants……Page 772
Fig. 10 Equipment Dimensions and Force Locations for Wind Examples 5, 6, and 7……Page 773
Bibliography……Page 774
Codes and Standards……Page 775
Contributors……Page 776