ASHRAE 2000 HVAC Systems and Equipment Handbook

Cover......Page 1
Preface......Page 2
System Constraints......Page 3
Table 1 Sample HVAC System Selection Matrix (0 to 10 Score)......Page 4
Decentralized System Features......Page 5
HVAC Facilities......Page 6
Air Terminal Units......Page 7
Standards......Page 8
All-Air Systems......Page 9
Other Considerations......Page 10
Fig. 1 Equipment Arrangement for Central System Draw-Through Unit......Page 11
Fig. 3 Water Spray Cooling......Page 12
Dehumidification......Page 13
Automatic Dampers......Page 14
Preheat Coil......Page 15
Outside Air Requirements......Page 16
Constant Volume......Page 17
Fig. 10 Variable Air Volume with Reheat, Induction and Fan-Powered Devices......Page 18
Variable Air Volume......Page 19
Compressed Air and Water Spray System......Page 20
VAV Terminal Units......Page 21
Air Distribution System Controls......Page 22
References......Page 23
System Description......Page 24
Fan-Coil Units......Page 25
Fig. 3 Typical Fan-Coil Unit Arrangements......Page 26
Water Distribution......Page 27
Primary Air Systems......Page 28
Fig. 6 Solar Radiation Variations with Seasons......Page 29
With Central Ventilation......Page 30
Changeover Temperature Considerations......Page 31
Fig. 11 Typical Nonchangeover System Variations......Page 32
Zoning......Page 33
Bibliography......Page 34
Cooling Towers......Page 35
Working Pressure......Page 36
Space Requirements......Page 37
Central Plant Loads......Page 38
Disadvantages of Packaged Systems......Page 39
Through-the-Wall and Window-Mounted Air Conditioners and Heat Pumps......Page 40
Fig. 3 Packaged Terminal Air Conditioner with Combination Heating and Cooling Chassis......Page 41
Advantages......Page 42
Controls......Page 43
Acoustics......Page 44
Controls......Page 45
Design Considerations......Page 46
Design Considerations......Page 47
References......Page 48
General Evaluation......Page 49
Radiation Transfer......Page 50
Convection Transfer......Page 51
Combined Heat Transfer (Radiation and Convection)......Page 52
General Design Considerations......Page 53
Effect of Floor Coverings......Page 54
Design of Panels......Page 55
Fig. 9 Design Graph for Heating and Cooling with Floor and Ceiling Panels......Page 56
Fig. 10 Design Graph for Heating with Aluminum Ceilings and Wall Panels......Page 57
Fig. 11 Primary/Secondary Water Distribution System with Mixing Control......Page 58
Hydronic Metal Ceiling Panels......Page 60
Fig. 15 Extruded Aluminum Panels with Integral Copper Tube......Page 61
Fig. 19 Coils in Plaster below Lath......Page 62
Fig. 21 Embedded Tube in Thin Slab......Page 63
Fig. 24 Electric Heating Panels......Page 64
Electrically Heated Floors......Page 65
Fig. 25 Electric Heating Panel for Wet Plaster Ceiling......Page 66
Cooling Controls......Page 67
Bibliography......Page 68
Reciprocating Engines......Page 69
Fig. 2 Opposed-Piston Engine......Page 70
Fig. 4 Heat Rate of Spark Ignition Engines......Page 71
Fuel Oil Systems......Page 72
Lubricating Systems......Page 73
Alarm and Shutdown Controls......Page 74
Table 2 Recommended Engine Maintenance......Page 75
Components......Page 76
Starting Systems......Page 77
Advantages of CTIAC......Page 78
Fig. 15 Turbine Engine Performance Characteristics......Page 79
Axial Flow Turbines......Page 80
Governing Systems......Page 81
Fig. 20 Multivalve Oil Relay Governor......Page 82
Performance Characteristics......Page 83
Fig. 23 Effect of Inlet Pressure and Superheat on Condensing Turbine......Page 84
Table 4 Theoretical Steam Rates For Turbines at Common Conditions, kg/kWh......Page 85
Economics......Page 86
Fig. 28 Heat Balance for Turbocharged Engine......Page 87
Reciprocating Engines......Page 88
Fig. 32 Engine Cooling with Gravity Circulation and Steam Heat Recovery......Page 89
Fig. 34 Exhaust Heat Recovery with Steam Separator......Page 90
Fig. 38 Effect of Lowering Exhaust Temperature below 150C......Page 91
Steam Turbines......Page 92
Fig. 41 Condensing Automatic Extraction Turbine......Page 93
Fig. 44 Exhaust Gas Chiller-Heater......Page 94
Fig. 45 Typical Generator Efficiency......Page 95
United States Laws and Regulations......Page 96
Steam......Page 97
Cogeneration Utilization Systems......Page 98
Unitary and Packaged HVAC Systems......Page 99
Load Profiling and Prime Mover Selection......Page 100
Thermal Energy Storage Technologies......Page 101
Fig. 46 Typical Combined-Cycle Power Plant Schematic......Page 102
Jacket Water Systems......Page 103
Exhaust Systems......Page 104
Combustion Air Systems......Page 105
Off-Engine Instruments and Controls......Page 106
Noise and Vibration Control......Page 107
Table 12 Percent Minimum Engine Reserves for Air Conditioning and Refrigeration......Page 108
Fig. 49 Heat Balance for Engine-Driven Heat Pump......Page 109
Steam Turbine Applications......Page 110
Terminology......Page 111
Load Duration Curve Analysis......Page 112
Fig. 54 Load Duration Curve......Page 113
Two-Dimensional Load Duration Curve......Page 114
National Electrical Code (NFPA Standard 70-98)......Page 115
References......Page 116
Heat Pump Cycles......Page 117
Air......Page 118
Table 1 Heat Pump Sources and Sinks......Page 119
Types of Heat Pumps......Page 120
Fig. 5 Heat Pump Types......Page 121
Compressors......Page 122
Fig. 9 Typical Increase in Heating Capacity Resulting from Use of Liquid Subcooling Coil......Page 123
Industrial Process Heat Pumps......Page 124
Fig. 10 Dehumidification Heat Pump......Page 125
Fig. 12 Effluent Heat Recovery Heat Pump......Page 126
Fig. 13 Refrigeration Heat Recovery Heat Pump......Page 127
Fig. 16 Single-Effect Heat Pump Evaporator......Page 128
Heat Recovery Design Principles......Page 129
Fig. 20 Semi-Open Cycle Heat Pump in a Textile Plant......Page 130
Fig. 23 Heat Recovery Chiller with Storage Tank......Page 131
Fig. 26 Heat Loss and Heat Gain for Interior Zones During Occupied Periods......Page 132
Fig. 30 Secondary Heat Recovery from WLHP System......Page 133
Design Considerations......Page 134
Advantages of a WLHP System......Page 135
Heat Balance Studies......Page 136
Fig. 34 Non-Heat-Recovery System......Page 137
Bibliography......Page 138
Ducts......Page 139
Controls......Page 140
Fig. 2 Preferred Return Locations for Various Supply Outlet Positions......Page 141
Duct Configuration......Page 142
Table 2 Recommended Division of Duct Pressure Loss......Page 143
Sizing the Branch Supply Air Duct......Page 144
Zone Control for Small Systems......Page 145
Duct Sizing for Zone Damper Systems......Page 146
Fig. 10 Example Duct System and Equivalent Length and Extended Plenum Fittings......Page 147
Fig. 13 Equivalent Length (EL in Metres) of Angles and Elbows for Branch Ducts (ACCA 1995)......Page 148
Embedded Loop Ducts......Page 149
System Performance......Page 150
Implications......Page 151
Table 3 Definitions of System Performance Factors......Page 152
Table 5 Base Case Assumptions for Simulation Predictions......Page 153
Effect of Furnace Sizing......Page 154
Effects of Furnace Sizing and Night Setback......Page 155
Bibliography......Page 156
Fundamentals......Page 157
Steam Source......Page 158
Return Piping......Page 159
Design Steam Pressure......Page 160
Fig. 4 Method of Dripping Steam Mains......Page 161
Condensate Removal from TemperatureRegulated Equipment......Page 162
Thermostatic Traps......Page 163
Mechanical Traps......Page 164
Installation......Page 165
Fig. 13 Steam Supply......Page 166
Forced-Convection Units......Page 167
Fig. 16 Two-Pipe System......Page 168
Temperature Control......Page 169
Flash Steam......Page 170
Direct Heat Recovery......Page 171
References......Page 172
Environmental Benefits......Page 173
Central Plant......Page 174
Thermal Storage......Page 175
Constant Flow......Page 176
Fig. 4 Variable Flow Primary/Secondary Systems......Page 177
Pipe Sizing......Page 178
Thermal Properties of Pipe Insulation and Soil......Page 179
Table 2 Effect of Moisture on Underground Piping System Insulations (Chyu et al. 1997a,b; 1998a,b)......Page 180
Calculation of Undisturbed Soil Temperatures......Page 181
Fig. 5 Single Uninsulated Buried Pipe......Page 182
Single Buried Pipe in Conduit with Air Space......Page 183
Two Pipes Buried in Common Conduit with Air Space......Page 184
Two Buried Pipes or Conduits......Page 185
Fig. 9 Pipes in Buried Trenches or Tunnels......Page 186
Pipes in Shallow Trenches......Page 187
Economical Thickness for Pipe Insulation......Page 188
Pipe Supports, Guides, and Anchors......Page 189
Piping Materials and Standards......Page 190
Fig. 10 Walk-Through Tunnel......Page 191
Fig. 12 Deep-Bury Small Tunnel......Page 192
Conduits......Page 193
Fig. 18 Conduit System with Two Carrier Pipes and Annular Air Space......Page 194
Cathodic Protection of Direct-Buried Conduits......Page 195
Valve Vaults and Entry Pits......Page 196
Fig. 21 Direct Connection of Building System to District Hot Water......Page 198
Fig. 22 Basic Heating System Schematic......Page 199
Flow Control Devices......Page 200
Fig. 23 District/Building Interconnection with Heat Recovery Steam System......Page 201
Hot Water Connections......Page 202
Temperature Differential Control......Page 203
Metering......Page 204
References......Page 205
Bibliography......Page 206
Closed Water Systems......Page 207
Loads......Page 208
Expansion Chamber......Page 209
Fig. 3 Solubility Versus Temperature and Pressure for Air/Water Solutions......Page 210
Pump or Pumping System......Page 211
Fig. 8 Operating Conditions for Series Pump Installation......Page 212
Fig. 10 Tank Pressure Related to “System” Pressure......Page 213
Fig. 14 One-Pipe Diverting Tee System......Page 214
Fig. 16 Direct- and Reverse-Return Two-Pipe Systems......Page 215
Nonresidential Heating Systems......Page 216
Table 1 Chilled Water Coil Performance......Page 217
Two-Pipe Systems......Page 218
Makeup and Fill Water Systems......Page 219
Balance Fittings......Page 220
Final Pipe Sizing and Pressure Drop Determination......Page 221
Fig. 29 Example of Effect of Aqueous Ethylene Glycol Solutions on Heat Exchanger Output......Page 222
References......Page 223
Open Cooling Tower Systems......Page 225
Water Treatment......Page 226
Overpressure due to Thermal Fluid Expansion......Page 227
System Characteristics......Page 228
Direct-Fired High-Temperature Water Generators......Page 229
Fig. 4 Arrangement of Boiler Piping......Page 230
Fig. 6 HTW Piping for Combined (One-Pump) System (Steam Pressurized)......Page 231
Fig. 9 Inert Gas Pressurization for Two-Pump System......Page 232
System Circulating Pumps......Page 233
Distribution Piping Design......Page 234
Instrumentation and Controls......Page 235
References......Page 236
Gas Infrared......Page 238
Electric Infrared......Page 239
Oil Infrared......Page 240
Precautions......Page 241
Fig. 3 Relative Absorptance and Reflectance of Skin and Typical Clothing Surfaces......Page 242
Fig. 7 Radiant Flux Distribution Curve of Typical Broad- Beam High-Intensity Electric Infrared H.........Page 243
Fig. 10 Calculation of Total ERF from Three Gas-Fired Heaters on Worker Standing at Positions A .........Page 244
Bibliography......Page 245
Classification of Ducts......Page 246
Rectangular and Round Ducts......Page 247
Fibrous Glass Ducts......Page 248
Materials......Page 249
Underground Ducts......Page 250
References......Page 251
Procedure for Outlet Selection......Page 253
Variable Air Volume......Page 254
Linear Slot Outlets......Page 255
Types......Page 256
Applications......Page 257
Reheat Boxes......Page 258
Static Pressure Control......Page 259
References......Page 260
Principles of Operation......Page 261
Table 1 Types of Fans......Page 262
Fan Laws......Page 264
Fig. 6 Pressure Relationships of Fan with Inlet System Only......Page 265
Fig. 10 Example System Total Pressure Loss (Dp) Curves......Page 266
Parallel Fan Operation......Page 267
Control......Page 268
Bibliography......Page 269
Direct Evaporative Air Coolers......Page 270
Remote Pad Evaporative Cooling Equipment......Page 271
Heat Recovery......Page 272
Fig. 5 Indirect/Direct Evaporative Cooler with Heat Exchanger (Rotary Heat Wheel or Heat Pipe)......Page 273
Spray-Type Air Washers......Page 274
Humidification with Air Washers and Rigid Media......Page 275
Maintenance and Water Treatment......Page 276
Bibliography......Page 277
Process Control and Materials Storage......Page 278
Table 1 Maximum Relative Humidity in a Space for No Condensation on Windows......Page 279
Design Conditions......Page 280
Equipment......Page 281
Industrial and Commercial Humidifiers for Central Air Systems......Page 282
Fig. 3 Residential Humidifiers......Page 283
Fig. 4 Industrial Humidifiers......Page 284
Electronic Controllers......Page 285
Control Location......Page 286
References......Page 287
Water and Aqueous Glycol Coils......Page 288
Control of Coils......Page 289
Applications......Page 290
Fig. 6 Sprayed-Coil System with Air Bypass......Page 291
Performance and Ratings......Page 292
Heat Transfer......Page 293
Performance of Sensible Cooling Coils......Page 294
Performance of Dehumidifying Coils......Page 296
Fig. 9 Thermal Diagram for General Case When Coil Surface Operates Partially Dry......Page 297
Fig. 11 Typical Total Metal Thermal Resistance of Fin and Tube Assembly......Page 299
Fig. 12 Typical Air-Side Application Rating Data Determined Experimentally for Cooling and Dehum.........Page 300
Determining Refrigeration Load......Page 301
Symbols......Page 302
References......Page 303
Compression......Page 304
Desiccant Dehumidification......Page 305
Fig. 5 Liquid Desiccant System with Multiple Conditioners......Page 306
Fig. 7 Typical Rotary Dehumidification Unit......Page 307
Fig. 10 Effect of Changes in Reactivation Air Inlet Temperature on Dehumidifier Outlet Moisture......Page 308
Equipment Operating Concerns and Suggestions......Page 309
Commissioning......Page 310
Ventilation Air Preconditioning......Page 311
Adsorption......Page 312
Testing of Equipment......Page 313
Bibliography......Page 314
Coil Construction and Design......Page 315
Water/Aqueous Glycol Heating Coils......Page 316
Coil Selection......Page 317
Applications......Page 318
References......Page 319
Ventilation Air Cleaning......Page 320
Air Cleaner Test Methods......Page 321
Fig. 1 Typical Performance Curves for Fixed CartridgeType Filter According to ASHRAE Standard 52.1......Page 322
Miscellaneous Performance Tests......Page 323
Panel Filters......Page 324
Fig. 3 Comparative Performance of Viscous Impingement and Dry-Media Filters......Page 325
Electronic Air Cleaners......Page 326
Selection and Maintenance......Page 327
Table 2 Typical Filter Applications Classified by Filter Efficiency and Typea......Page 328
Table 3 Cross-Reference and Application Guidelines (Table E-1, ASHRAE Standard 52.2)......Page 330
Filter Installation......Page 329
Bibliography......Page 331
Gas-Cleaning Regulations......Page 333
Particulate Contaminant Control......Page 334
Settling Chambers......Page 335
Inertial Collectors......Page 336
Table 4 Collectors Used in Industry......Page 337
Table 5 Terminal Settling Velocities of Particles, m/s......Page 339
Fig. 5 Typical Two-Stage Electrostatic Precipitators......Page 340
Two-Stage Designs......Page 341
Fabric Filters......Page 342
Fig. 8 Time Dependence of Pressure Drop Across Fabric Filter......Page 343
Types of Self-Cleaning Mechanisms for Fabric Dust Collectors......Page 344
Fig. 12 Draw-Through Reverse Flow Cleaning of Fabric Filter......Page 345
Fig. 13 Typical Pulse Jet Fabric Filter......Page 346
Particulate Scrubbers (Wet Collectors)......Page 347
Fig. 17 Efficiency of Venturi Scrubber......Page 348
Venturi Scrubber......Page 349
Equipment......Page 350
Arrangements of Packed Scrubbers......Page 351
Fig. 26 Horizontal Flow Scrubber with Extended Surface......Page 352
Absorption Efficiency......Page 353
Fig. 30 Contaminant Control at Superficial Velocity = 0.6 m/s (Liquid Film Controlled)......Page 354
Fig. 34 Contaminant Control at Superficial Velocity = 1.2 m/s (Gas Film Controlled)......Page 355
Adsorption of Gaseous Contaminants......Page 356
Solvent Recovery......Page 357
Fig. 38 Schematic of Two-Unit Fixed Bed Adsorber......Page 358
Thermal Oxidizers......Page 359
Adsorption and Oxidation......Page 360
Hoppers......Page 361
References......Page 362
Bibliography......Page 363
Fig. 1 Typical Single-Port Upshot Gas Conversion Burner......Page 364
Unitary Heaters......Page 365
Compensation for Altitude......Page 366
Fig. 3 Details of High-Pressure Atomizing Oil Burner......Page 367
Return-Flow Pressure Atomizing Oil Burners......Page 368
Return-Flow Mechanical Atomizing Oil Burners......Page 369
Fuel Oil Storage Systems......Page 370
Fig. 5 Industrial Burner Auxiliary Equipment......Page 371
Capacity Classification of Stokers......Page 372
Spreader Stokers......Page 373
Fig. 8 Chain Grate Stoker......Page 374
Operating Controls......Page 375
Programming......Page 376
Bibliography......Page 377
Construction Materials......Page 378
Fig. 1 Residential Boilers......Page 379
Type of Draft......Page 380
Fig. 5 Effect of Inlet Water Temperature on Efficiency of Condensing Boilers......Page 381
Efficiency: Input and Output Ratings......Page 382
Control of Input and Output......Page 383
Bibliography......Page 384
Fig. 17 Typical Fan Operating Data and System Curves......Page 0
Burners and Internal Controls......Page 385
Airflow Variations......Page 386
Combustion System Variations......Page 387
Fig. 7 Electric Forced-Air Furnace......Page 388
Natural Gas Furnaces......Page 389
Electric Furnaces......Page 390
Natural Gas Furnaces......Page 391
Equipment Variations......Page 392
System Design and Equipment Selection......Page 393
Agency Listings......Page 394
Bibliography......Page 395
Wall Furnaces......Page 396
Thermostats......Page 397
Portable Kerosene Heaters......Page 398
Simple Fireplaces......Page 399
Advanced Design Wood Stoves......Page 400
Safety with Solid Fuels......Page 401
References......Page 402
Start-Up......Page 403
Steady-State Chimney Design Equations......Page 404
5. Chimney Gas Velocity......Page 405
Table 2 Typical Chimney and Vent Design Conditionsa......Page 406
Chimney Gas Temperature and Heat Transfer......Page 407
Table 5 Overall Heat Transfer Coefficients of Various Chimneys and Vents......Page 408
Table 8 Pressure Equations for Dp......Page 409
Resistance Coefficients......Page 410
Configuration and Manifolding Effects......Page 411
Fig. 5 Connector Design......Page 412
Chimney Capacity Calculation Examples......Page 413
Fig. 9 Forced-Draft Appliance with Positive Outlet Pressure......Page 414
Fig. 10 Illustration for Example 2......Page 415
Fig. 12 Illustration for Example 4......Page 416
Fig. 13 Illustration for Example 6......Page 417
Gas Appliance Venting......Page 418
Condensation and Corrosion......Page 419
Vent Connectors......Page 420
Fig. 15 Eddy Formation......Page 421
Vent and Chimney Materials......Page 422
Draft Hoods......Page 424
Fig. 18 Use of Barometric Draft Regulators......Page 425
Fig. 19 Draft Inducers......Page 426
Fig. 21 Height of Eddy Currents Around Single High-Rise Buildings......Page 427
Fig. 23 Vent and Chimney Rain Protection......Page 428
Symbols......Page 429
Bibliography......Page 430
Table 1 Typical Unit Ventilator Capacities......Page 431
Fig. 1 Typical Unit Ventilators......Page 432
Location......Page 433
Heating Medium......Page 434
Fig. 3 Typical Unit Heaters......Page 435
Ratings of Unit Heaters......Page 436
Maintenance......Page 437
Makeup Air Units......Page 438
Applicable Codes and Standards......Page 439
Bibliography......Page 440
Finned-Tube Units......Page 441
Ratings of Heat-Distributing Units......Page 442
Corrections for Nonstandard Conditions......Page 443
Effect of Altitude......Page 444
Finned-Tube Radiation......Page 445
Bibliography......Page 446
Liquid Heating Systems......Page 447
Fig. 3 Simplified Schematic of Indirect Drain-Back Freeze Protection System......Page 448
Fig. 5 Evacuated Tube Collector......Page 449
Collector Performance......Page 450
Fig. 6 Plan View of Liquid Collector Absorber Plates......Page 451
Fig. 8 Air Collectors with External Manifolds......Page 452
Fig. 11 Collector Efficiencies of Various Liquid Collectors......Page 453
Table 1 Collector Intercept and Slope by Generic Type......Page 454
Velocity Limitations......Page 455
Piping Configuration......Page 456
Shading......Page 457
Liquid System Thermal Storage......Page 458
Fig. 23 Unpressurized Storage System with External Heat Exchanger......Page 459
Storage Tank Insulation......Page 460
Sizing......Page 461
Fig. 26 Cross Section of Wraparound Shell Heat Exchangers......Page 462
Heat Exchanger Performance......Page 463
Over-Temperature Protection......Page 464
Heat Exchanger Freeze Protection......Page 465
Photovoltaic Cells and Modules......Page 466
References......Page 467
Bibliography......Page 468
Actual Compressor Performance......Page 469
Protective Devices......Page 470
Motors......Page 471
Performance Data......Page 472
Table 2 Typical Performance Values for Reciprocating Compressors......Page 473
Motor Performance......Page 474
Features......Page 475
Special Devices......Page 476
Fig. 4 Fixed Vane, Rolling Piston Rotary Compressor......Page 477
Fig. 6 Sound Level of Combination Refrigerator-Freezer with Typical Rotary Compressor......Page 478
Compression Process......Page 479
Fig. 10 Radial and Axially Balanced Main Rotor......Page 480
Fig. 12 Schematic of Oil-Injection-Free Circuit......Page 481
Fig. 14 Theoretical Economizer Cycle......Page 482
Fig. 18 Capacity Slide in Part-Load Position and Volume Ratio Slide Positioned to Maintain Syste.........Page 483
Fig. 22 Typical Semihermetic Single-Screw Compressor......Page 484
Mechanical Features......Page 485
Volume Ratio......Page 486
Fig. 28 View of Fixed and Variable Volume Ratio (Vi) Slide Valves from Above......Page 487
Oil Injection......Page 488
Hermetic Compressors......Page 489
Mechanical Features......Page 490
Fig. 35 Bearings and Other Components of Scroll Compressor......Page 491
Noise and Vibration......Page 492
Description and Performance......Page 493
Fig. 44 Compression Cycle with Power Recovery Expander......Page 494
Isentropic Analysis......Page 495
Polytropic Analysis......Page 496
Nondimensional Coefficients......Page 497
Performance......Page 498
Capacity Control......Page 499
Critical Speed......Page 500
Drivers......Page 501
Lubrication......Page 502
Operation and Maintenance......Page 503
References......Page 504
Fig. 1 Heat Removed in Condenser......Page 505
Refrigerant-Side Film Coefficient......Page 506
Fouling Factor......Page 507
Water Pressure Drop......Page 508
Shell-and-Tube Condensers......Page 509
Noncondensable Gases......Page 510
Operation and Maintenance......Page 511
Coil Construction......Page 512
Heat Transfer and Pressure Drop......Page 513
Application and Rating of Condensers......Page 514
Control of Air-Cooled Condensers......Page 515
Fig. 9 Unit Condensers Installed in Parallel with Combined Fan Cycling and Damper Control......Page 516
Fig. 10 Air-Cooled Unit Condenser for Winter Heating and Summer Ventilation......Page 517
Fig. 12 Heat Transfer Diagram for Evaporative Condenser......Page 518
Airflow......Page 519
Fig. 16 Parallel Operation of Two Evaporative Condensers......Page 520
Multicircuit Condensers and Coolers......Page 521
Table 2 Maintenance Checklist......Page 522
References......Page 523
Fig. 1 Temperature Relationship Between Water and Air in Counterflow Cooling Tower......Page 525
Fig. 3 Direct-Contact or Open Evaporative Cooling Tower......Page 526
Types of Direct-Contact Cooling Towers......Page 527
Fig. 11 Factory-Assembled Counterflow Forced-Draft Tower......Page 528
Fig. 12 Field-Erected Cross-Flow Mechanical-Draft Tower......Page 529
Types of Indirect-Contact Towers......Page 530
Siting......Page 531
Fig. 17 Cooling Tower Fan Power Versus Speed......Page 532
Fig. 20 Free Cooling by Interconnection of Water Circuits......Page 533
Fogging (Cooling Tower Plume)......Page 534
Inspections......Page 535
Fig. 23 Cooling Tower Performance—67% Design Flow......Page 537
Cooling Tower Thermal Performance......Page 538
Fig. 26 Heat and Mass Transfer Relationships Between Water, Interfacial Film, and Air......Page 539
Fig. 27 Counterflow Cooling Diagram......Page 540
Fig. 30 Cross-Flow Cooling Diagram......Page 541
Fig. 32 Tower Characteristic, KaV/L Versus L/G......Page 542
Bibliography......Page 543
Table 1 Types of Coolers......Page 544
Heat Transfer......Page 545
Fig. 5 Nucleate Boiling Contribution to Total Refrigerant Heat Transfer......Page 546
Chemical Requirements......Page 547
References......Page 548
Basic System......Page 550
Fig. 2 Decoupled System......Page 551
Equipment Selection......Page 552
Controls That Influence the Liquid Chiller......Page 553
Regularly Scheduled Maintenance......Page 554
Fig. 7 Comparison of Single-Stage Centrifugal, Reciprocating, and Screw Compressor Performance......Page 555
Fig. 9 Reciprocating Liquid Chiller Control System......Page 556
Selection of Refrigerant......Page 557
Fig. 11 Typical Centrifugal Compressor Performance at Various Speeds......Page 558
Control Considerations......Page 559
Heat Recovery......Page 560
Components and Their Function......Page 561
Performance and Operating Characteristics......Page 562
Fig. 15 Typical External Connections for Screw Compressor Chiller......Page 563
Maintenance......Page 564
Fig. 1 Cross Section of Typical Overhung-Impeller End-Suction Pump......Page 565
Close-Coupled, Single-Stage, End-Suction Pump......Page 566
Fig. 10 Vertical Turbine Pumps......Page 567
Hydronic System Curves......Page 568
Fig. 17 System and Pump Curves......Page 569
Pump Efficiency......Page 570
Fig. 24 Pump Best Efficiency Curves......Page 571
Fig. 27 Variable-Speed Pump Operating Points......Page 572
Fig. 30 Pump Performance and NPSR Curves......Page 573
Parallel Pumping......Page 574
Fig. 38 Typical Piping for Series Pumps......Page 575
Distributed Pumping......Page 576
Installation, Operation, and Commissioning......Page 577
Table 3 Pumping System Flow Analysis Guide......Page 578
Bibliography......Page 579
Codes and Standards......Page 580
General-Purpose Induction Motors......Page 581
Application......Page 582
Integral Thermal Protection......Page 583
Table 4 Characteristics of AC Motors (Nonhermetic)......Page 584
Protection of Control Apparatus and Branch Circuit Conductors......Page 585
Air Volume Control......Page 586
Motor and Conductor Impedance......Page 587
Fig. 9 AC Drive Control......Page 588
Motor Noise and Drive Carrier Frequencies......Page 589
Power Distribution System Effects......Page 590
Fig. 18 Basic Elements of Solid-State Drive......Page 591
Bibliography......Page 592
Copper Tube......Page 593
Soldering and Brazing......Page 594
Table 2 Steel Pipe Data......Page 595
Table 3 Copper Tube Data......Page 596
Other Joints......Page 597
Selection of Materials......Page 598
Plastic Piping......Page 599
Table 7 Properties of Plastic Pipe Materialsa......Page 600
Plastic Material Selection......Page 601
Table 10 Thermal Expansion of Metal Pipe......Page 602
Z Bends......Page 603
Expansion Joints and Expansion Compensating Devices......Page 604
Fig. 5 Flexible Ball Joint......Page 605
Bibliography......Page 606
Materials......Page 607
Noise......Page 608
Plug Valves......Page 609
Actuators......Page 610
Solenoids......Page 611
Fig. 13 Typical Three-Way Control Applications......Page 612
Fig. 16 Control Valve Flow Characteristics......Page 613
Control Valve Sizing......Page 614
Fig. 20 Manual Balancing Valve......Page 615
Fig. 24 Typical Multiple-Purpose Valve (Angle Pattern) on Discharge of Pump......Page 616
Fig. 26 Self-Operated Temperature Control Valve......Page 617
Fig. 28 Swing Check Valves......Page 618
Bibliography......Page 619
Types of Heat Exchangers......Page 621
Fig. 7 Straight-Tube Floating Tubesheet Shell-and-Tube Heat Exchanger with Removable Bundle Asse.........Page 622
Components......Page 623
Application......Page 624
Installation......Page 625
Economic Considerations......Page 627
Principle of Operation......Page 645
Ideal Air-to-Air Energy Exchange......Page 628
Rate of Energy Transfer......Page 629
Fig. 1 Airstream Numbering Convention......Page 630
Pressure Drop......Page 631
Controls......Page 632
Energy Recovery Calculations......Page 633
Fig. 6 Maximum Sensible and Latent Heat from Process A-B......Page 634
Fig. 8 Sensible Heat Recovery in Winter with Condensate (Example 3)......Page 635
Fig. 10 Indirect Evaporative Cooling Recovery (Example 5)......Page 636
Fig. 12 Fixed-Plate Cross-Flow Heat Exchanger......Page 637
Differential Pressure/Cross-Leakage......Page 638
Construction......Page 639
Maintenance......Page 640
Construction Materials......Page 641
Performance......Page 642
Twin Tower Enthalpy Recovery Loops......Page 643
Fig. 24 Typical Performance of Two-Phase Thermosiphon Loop......Page 644
Installation......Page 646
Fig. 6 Through-the-Wall Installation of Air-Cooled Single-Package Unit......Page 647
Types of Unitary Equipment......Page 648
Fig. 7 Residential Installation of Split-System Air-Cooled Condensing Unit with Coil and Upflow .........Page 649
ARI Certification Programs......Page 650
Capacity Control......Page 651
Mechanical Design......Page 652
Selection......Page 653
Refrigerant Charge Management......Page 654
Systems......Page 655
Equipment Design......Page 656
Fig. 15 Water-Source Heat Pump Systems......Page 657
References......Page 658
Design......Page 659
Sensible Heat Ratio......Page 660
Special Features......Page 661
Installation and Service......Page 662
General Design Considerations......Page 663
Design of PTAC/PTHP Components......Page 664
Design and Construction......Page 665
References......Page 666
Engines......Page 667
Rating and Performance......Page 668
Maintenance and Service......Page 669
Noise and Vibration Control......Page 670
Emissions and Permitting......Page 671
Engine Room Ventilation and Combustion Air Requirements......Page 672
Fig. 9 Four-Pipe Heat Pump......Page 673
Fig. 12 Performance Characteristics of Multisplit Engine-Driven Heat Pump......Page 674
Outdoor Coil Circuitry......Page 675
Fig. 14 Effect of Low Temperature Chilling on Nominal Rating of Engine-Driven Chiller with Screw.........Page 676
Bibliography......Page 677
Table 1 Codes and Standards Published by Various Societies and Associations (Continued)......Page 678
Table 2 ABBREVIATIONS AND ADDRESSES......Page 699
Contributors......Page 700