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Refrigeration & Air Conditioning Technology 9th edition [Kõva köide]

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(HVAC Excellence, The ESCO Institute, Mount Prospect, IL), , (Retired from Ferris State University), (Director of Industry Relations and Standards, The ESCO Institute, Mount Prospect, IL),
  • Formaat: Hardback, 1728 pages, kõrgus x laius x paksus: 58x238x276 mm, kaal: 3810 g
  • Ilmumisaeg: 01-Jan-2020
  • Kirjastus: Delmar Cengage Learning
  • ISBN-10: 0357122275
  • ISBN-13: 9780357122273
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Refrigeration & Air Conditioning Technology 9th editionSuurem pilt
  • Formaat: Hardback, 1728 pages, kõrgus x laius x paksus: 58x238x276 mm, kaal: 3810 g
  • Ilmumisaeg: 01-Jan-2020
  • Kirjastus: Delmar Cengage Learning
  • ISBN-10: 0357122275
  • ISBN-13: 9780357122273
Teised raamatud teemal:
Püsilink: https://www.kriso.ee/db/9780357122273.html
Märksõnad:
Develop the knowledge and skills you need to maintain and troubleshoot today's complex heating, air conditioning, and refrigeration systems with REFRIGERATION & AIR CONDITIONING TECHNOLOGY, Ninth Edition. This best-selling, easy-to-understand resource provides hands-on guidance, practical applications, and the solid foundation you need to understand modern HVAC service and repair, its environmental challenges, and their solutions. Focused on sustainable technology and emphasizing new technologies and green awareness, the Ninth Edition features the latest advances in the HVAC/R industry, including updated content throughout the text and more than 400 new and revised figures and images. Drawing on decades of industry experience, the authors also cover the all-important soft skills and customer relations issues that today's professionals need to master for career success. Memorable real-world examples, hundreds of vibrant photos, and unique Service Call features bring key concepts to life and help you develop the knowledge and skills to succeed in today's dynamic industry.
Preface xiii
New to This Edition
xiv
How to Use This Text and Supplementary Materials
xiv
Support Materials
xviii
About the Authors
xx
Acknowledgments
xxii
Section 1: Theory of Heat
Introduction
2(14)
History of Refrigeration and Air-Conditioning (Cooling)
2(4)
Green Awareness
6(1)
History of Home and Commercial Heating
7(1)
Career Opportunities
8(1)
Technician Certification Programs
9(1)
Programmatic Accreditation
10(1)
National Skill Standards
11(1)
Customer Relations and Technician Soft Skills
11(5)
Unit 1 Heat, Temperature, and Pressure
16(14)
1.1 Heat, Temperature, and Pressure
16(1)
1.2 Temperature
17(1)
1.3 Introduction to Heat
18(2)
1.4 Conduction
20(1)
1.5 Convection
20(1)
1.6 Radiation
21(1)
1.7 Sensible Heat
22(1)
1.8 Latent Heat
22(2)
1.9 Specific Heat
24(1)
1.10 Sizing Heating Equipment
24(1)
1.11 Pressure
25(1)
1.12 Atmospheric Pressure
26(1)
1.13 Pressure Gauges
27(3)
Unit 2 Matter and Energy
30(10)
2.1 Matter
30(1)
2.2 Mass and Weight
31(1)
2.3 Density
31(1)
2.4 Specific Gravity
31(1)
2.5 Specific Volume
31(2)
2.6 Gas Laws
33(2)
2.7 Energy
35(1)
2.8 Conservation of Energy
36(1)
2.9 Thermal Energy
36(1)
2.10 Energy in Magnetism
36(1)
2.11 Purchase of Energy
37(1)
2.12 Energy Used as Work
37(1)
2.13 Power
37(1)
2.14 Electrical Power-The Watt
37(3)
Unit 3 Refrigeration and Refrigerants
40(38)
3.1 Introduction to Refrigeration
40(1)
3.2 Refrigeration
41(1)
3.3 Rating Refrigeration Equipment
41(1)
3.4 The Refrigeration Process
42(1)
3.5 Temperature and Pressure Relationship
43(4)
3.6 Basic Refrigeration System Components
47(1)
3.7 The Evaporator
48(2)
3.8 The Compressor
50(2)
3.9 The Condenser
52(2)
3.10 The Refrigerant Metering Device
54(1)
3.11 A High-Temperature, Matched Refrigeration System by the Numbers
55(2)
3.12 Refrigerants
57(2)
3.13 Refrigerants Must Be Safe
59(1)
3.14 Refrigerants Must Be Detectable
59(1)
3.15 The Boiling Point of the Refrigerant
60(1)
3.16 Pumping Characteristics
61(1)
3.17 Popular Refrigerants and Their Important Characteristics
61(1)
3.18 Refrigerant Cylinder Color Codes
61(1)
3.19 Recovery, Recycling, and Reclaiming of Refrigerants
61(2)
3.20 Plotting the Refrigeration Cycle
63(9)
3.21 Plotting the Refrigeration Cycle for Blends with Noticeable Temperature Glide (Zeotropic Blends)
72(6)
Section 2: Safety, Tools and Equipment, and Shop Practices
Unit 4 General Safety Practices
78(19)
4.1 Workplace Surroundings and Personal Protective Equipment (PPE)
78(1)
4.2 Pressurized Vessels, Piping, and Systems
79(3)
4.3 Electrical Safety
82(4)
4.4 First Aid
86(1)
4.5 Ladder Safety
87(1)
4.6 Heat
88(2)
4.7 Cold
90(1)
4.8 Mechanical Equipment
90(1)
4.9 Moving Heavy Objects
91(1)
4.10 Refrigerants in Your Breathing Space
91(3)
4.11 Using Chemicals
94(3)
Unit 5 Tools, Instrumentation, and Equipment
97(36)
5.1 Introduction to Tools, Instrumentation, and Equipment
97(1)
5.2 Hand Tools
98(9)
5.3 Power Tools
107(1)
5.4 Electrical Test Instruments
108(2)
5.5 Refrigerant Leak Detectors
110(2)
5.6 Tubing Tools
112(3)
5.7 Piping Tools
115(1)
5.8 Sheet Metal Tools
116(1)
5.9 HVACR Installation and Service Tools and Equipment
117(8)
5.10 Airside Instrumentation
125(1)
5.11 Combustion Testing Equipment
126(2)
5.12 Energy Auditing Instrumentation
128(5)
Unit 6 Fasteners
133(16)
6.1 Nails
133(1)
6.2 Staples and Rivets
134(1)
6.3 Screws
135(2)
6.4 Hollow Wall Fasteners
137(2)
6.5 Concrete Fasteners
139(1)
6.6 Threaded Rod
140(1)
6.7 Piping and Ductwork Fasteners
141(1)
6.8 Pins, Clamps, and Rings
142(3)
6.9 Electrical Fasteners
145(4)
Unit 7 Tubing and Piping
149(33)
7.1 Purpose of Tubing and Piping
149(1)
7.2 Types and Sizes of Tubing
149(1)
7.3 Tubing Insulation
150(2)
7.4 Line Sets
152(1)
7.5 Cutting Tubing
152(1)
7.6 Bending Tubing
153(2)
7.7 Soldering and Brazing Processes
155(1)
7.8 Heat Sources for Soldering and Brazing
156(6)
7.9 Fluxing
162(1)
7.10 Soldering Techniques
163(2)
7.11 Brazing Techniques
165(1)
7.12 Practical Soldering and Brazing Tips
166(3)
7.13 Making Flare Joints
169(1)
7.14 Swaging Techniques
170(1)
7.15 Compression Fittings
171(1)
7.16 Steel and Wrought Iron Pipe
172(4)
7.17 Installing Steel Pipe
176(1)
7.18 Plastic Pipe
176(2)
7.19 Alternative Mechanical Piping Connections
178(4)
Unit 8 Leak Detection, System Evacuation, and System Cleanup
182(35)
8.1 Leaks
182(2)
8.2 Basic Refrigerant Leak Detection
184(2)
8.3 Advanced Leak Detection
186(2)
8.4 Standing Pressure Test
188(3)
8.5 Leak Detection Tips
191(2)
8.6 Repairing Leaks
193(1)
8.7 System Evacuation
194(12)
8.8 General Evacuation Procedures
206(6)
8.9 Cleaning a Dirty System
212(5)
Unit 9 Refrigerant and Oil Chemistry and Management-Recovery, Recycling, Reclaiming, and Retrofitting
217(37)
9.1 Refrigerants and the Environment
217(1)
9.2 Ozone Depletion
218(1)
9.3 Global Warming
219(1)
9.4 Refrigerants
220(1)
9.5 CFC Refrigerants
220(1)
9.6 HCFC Refrigerants
221(1)
9.7 HFC Refrigerants
221(1)
9.8 Hydrofluoro-Olefin (HFO) Refrigerants
222(1)
9.9 Hydrocarbon (HC) Refrigerants
223(4)
9.10 Refrigerant Numbering
227(1)
9.11 Refrigerant Blends
228(2)
9.12 Popular Refrigerants and Their Compatible Oils
230(5)
9.13 Refrigerant Oils and Their Applications
235(2)
9.14 Regulations
237(1)
9.15 Recover, Recycle, or Reclaim
237(2)
9.16 Methods of Recovery
239(3)
9.17 Mechanical Recovery Systems
242(4)
9.18 Recovering Refrigerant from Small Appliances
246(3)
9.19 Reclaiming Refrigerant
249(1)
9.20 Refrigerant Retrofitting
249(5)
Unit 10 System Charging
254(17)
10.1 Charging a Refrigeration System
254(1)
10.2 Vapor Refrigerant Charging
254(2)
10.3 Liquid Refrigerant Charging
256(3)
10.4 Weighing Refrigerant
259(1)
10.5 Graduated Charging Cylinders
260(1)
10.6 Charging Charts
261(3)
10.7 Subcooling Charging Method for TXV Systems
264(2)
10.8 Charging Near-Azeotropic (Zeotropic) Refrigerant Blends
266(5)
Unit 11 Calibrating Instruments
271(13)
11.1 Calibration
271(1)
11.2 Temperature-Measuring Instruments
271(4)
11.3 Pressure Test Instruments
275(1)
11.4 Electrical Test Instruments
276(2)
11.5 Electronic Refrigerant Leak Detection Devices
278(1)
11.6 Flue-Gas Analysis Instruments
278(2)
11.7 General Maintenance
280(4)
Section 3: Automatic Controls
Unit 12 Basic Electricity and Magnetism
284(31)
12.1 Atomic Structure
284(1)
12.2 The Law of Charges
285(1)
12.3 Conductors
286(1)
12.4 Insulators
286(1)
12.5 Electricity Produced from Magnetism
286(1)
12.6 Current
287(1)
12.7 Units of Electrical Measurement
287(1)
12.8 The Basic Electric Circuit
288(1)
12.9 Making Electrical Measurements
288(3)
12.10 Ohm's Law
291(1)
12.11 Characteristics of Series Circuits
292(1)
12.12 Characteristics of Parallel Circuits
292(1)
12.13 Electrical Power
293(1)
12.14 Magnetism
294(1)
12.15 Inductance
295(1)
12.16 Transformers
295(2)
12.17 Capacitance
297(1)
12.18 Impedance
298(1)
12.19 Electrical Measuring Instruments
298(4)
12.20 Sine Waves
302(2)
12.21 Wire Sizes
304(1)
12.22 Circuit Protection Devices
305(2)
12.23 Semiconductors
307(8)
Unit 13 Introduction to Automatic Controls
315(14)
13.1 Types of Automatic Controls
315(1)
13.2 Devices That Respond to Thermal Change
316(1)
13.3 The Bimetal Device
317(3)
13.4 Control by Fluid Expansion
320(2)
13.5 The Thermocouple
322(2)
13.6 Electronic Temperature-Sensing Devices
324(1)
13.7 Electronic Pressure-Sensing Devices
325(4)
Unit 14 Automatic Control Components and Applications
329(29)
14.1 Temperature Controls
329(2)
14.2 Low-Voltage Space Temperature Controls
331(3)
14.3 Line-Voltage Space Temperature Controls
334(3)
14.4 Sensing the Temperature of Solids
337(3)
14.5 Measuring the Temperature of Fluids
340(1)
14.6 Pressure-Sensing Devices
341(4)
14.7 Pressure Transducers
345(1)
14.8 High-Pressure Controls
346(1)
14.9 Low-Pressure Controls
346(1)
14.10 Oil Pressure Safety Controls
347(2)
14.11 Air Pressure Controls
349(1)
14.12 Gas Pressure Switches
350(1)
14.13 Switchless Control Devices
350(1)
14.14 Water Pressure Regulators
350(1)
14.15 Gas Pressure Regulators
351(1)
14.16 Mechanical and Electromechanical Controls
352(1)
14.17 Maintenance of Mechanical Controls
352(1)
14.18 Maintenance of Electromechanical Controls
353(1)
14.19 Service Technician Calls
353(5)
Unit 15 Troubleshooting Basic Controls
358(24)
15.1 Introduction to Troubleshooting
358(1)
15.2 Troubleshooting a Simple Circuit
359(1)
15.3 Troubleshooting a Complex Circuit
360(3)
15.4 Troubleshooting the Thermostat
363(2)
15.5 Troubleshooting Amperage in the Low-Voltage Circuit
365(1)
15.6 Troubleshooting Voltage in the Low-Voltage Circuit
366(1)
15.7 Troubleshooting Switches and Loads
366(7)
15.8 Pictorial and Ladder Diagrams
373(2)
15.9 Service Technician Calls
375(7)
Unit 16 Advanced Automatic Controls-Direct Digital Controls (DDCs) and Pneumatics
382(24)
16.1 Control Applications
382(1)
16.2 Types of Control Systems
382(2)
16.3 Pneumatic Controls
384(1)
16.4 Cleaning and Drying Control Air
385(1)
16.5 Control Components
386(5)
16.6 Direct Digital Controls (DDCs)
391(7)
16.7 Residential Electronic Controls
398(8)
Section 4: Electric Motors
Unit 17 Types of Electric Motors
406(32)
17.1 Uses of Electric Motors
406(1)
17.2 Parts of an Electric Motor
406(1)
17.3 Electric Motors and Magnetism
407(1)
17.4 Determining a Motor's Speed
408(1)
17.5 Start Windings
409(1)
17.6 Starting and Running Characteristics
409(1)
17.7 Electrical Power Supplies
410(2)
17.8 Single-Phase Open Motors
412(1)
17.9 Split-Phase Motors
412(1)
17.10 The Centrifugal Switch
412(2)
17.11 The Electronic Relay
414(1)
17.12 Capacitor-Start Motors
414(1)
17.13 Capacitor-Start, Capacitor-Run Motors
415(1)
17.14 Permanent Split-Capacitor (PSC) Motors
415(2)
17.15 Shaded-Pole Motors
417(1)
17.16 Three-Phase Motors
417(2)
17.17 Hermetically Sealed Motors
419(1)
17.18 The Potential Relay
420(2)
17.19 Troubleshooting
422(1)
17.20 The Current Relay
422(1)
17.21 Positive Temperature Coefficient Resistor (PTCR)
423(1)
17.22 Troubleshooting the PTCR
424(1)
17.23 Two-Speed Compressor Motors
424(1)
17.24 Special Application Motors
424(1)
17.25 Three-Phase Compressor Motors
425(1)
17.26 Variable-Speed Motors
426(3)
17.27 DC Converters (Rectifiers)
429(2)
17.28 Inverters and Variable Frequency Drives (VFDs)
431(3)
17.29 Electronically Commutated Motors (ECMs)
434(1)
17.30 Cooling Electric Motors
435(3)
Unit 18 Application of Motors
438(18)
18.1 Motor Applications
438(1)
18.2 The Power Supply
438(7)
18.3 Electric-Motor Working Conditions
445(1)
18.4 Insulation Type or Class
446(1)
18.5 Types of Bearings
446(2)
18.6 Motor Mounting Characteristics
448(2)
18.7 Motor Drives
450(6)
Unit 19 Motor Controls
456(11)
19.1 Introduction to Motor Control Devices
456(1)
19.2 Full-Load and Locked-Rotor Amperage
457(1)
19.3 The Relay
457(1)
19.4 The Contactor
458(2)
19.5 Motor Starters
460(1)
19.6 Motor Protection
461(1)
19.7 Inherent Motor Protection
462(1)
19.8 External Motor Protection
462(2)
19.9 National Electrical Codes Standards
464(1)
19.10 Temperature-Sensing Devices
464(1)
19.11 Magnetic Overload Devices
465(1)
19.12 Restarting the Motor
465(2)
Unit 20 Troubleshooting Electric Motors
467(19)
20.1 Motor Troubleshooting
467(1)
20.2 Mechanical Motor Problems
467(1)
20.3 Removing Drive Assemblies
468(1)
20.4 Belt Tension
469(1)
20.5 Pulley Alignment
470(1)
20.6 Electrical Problems
470(1)
20.7 Open Windings
471(1)
20.8 Shorted Motor Windings
471(2)
20.9 Short Circuit to Ground (Frame)
473(3)
20.10 Single-Phase Motor Starting Problems
476(1)
20.11 Checking Capacitors
476(2)
20.12 Capacitor Identification
478(2)
20.13 Wiring and Connectors
480(1)
20.14 Troubleshooting Hermetic Motors
480(1)
20.15 Service Technician Calls
480(6)
Section 5: Commercial Refrigeration
Unit 21 Evaporators and the Refrigeration System
486(23)
21.1 Refrigeration
486(1)
21.2 Temperature Ranges of Refrigeration
487(1)
21.3 The Evaporator
487(1)
21.4 Boiling and Condensing
488(1)
21.5 The Evaporator and Boiling Temperature
488(1)
21.6 Removing Moisture
488(1)
21.7 Heat Exchange Characteristics of the Evaporator
489(1)
21.8 Types of Evaporators
490(5)
21.9 Evaporator Evaluation
495(2)
21.10 Latent Heat in the Evaporator
497(1)
21.11 The Flooded Evaporator
497(1)
21.12 Dry-Type Evaporator Performance
497(1)
21.13 Evaporator Superheat
498(1)
21.14 Hot Pulldown (Excessively Loaded Evaporator)
498(1)
21.15 Pressure Drop in Evaporators
499(2)
21.16 Liquid Cooling Evaporators (Chillers)
501(1)
21.17 Evaporators for Low-Temperature Applications
502(1)
21.18 Defrost Methods
503(1)
21.19 Evaporator and Defrost Efficiency Controller
504(5)
Unit 22 Condensers
509(34)
22.1 The Condenser
509(1)
22.2 Water-Cooled Condensers
509(1)
22.3 Tube-Within-a-Tube Condensers
510(1)
22.4 Mineral Deposits
510(2)
22.5 Cleanable Tube-Within-a-Tube Condensers
512(2)
22.6 Shell-and-Coil Condensers
514(1)
22.7 Shell-and-Tube Condensers
514(1)
22.8 Wastewater Systems
514(3)
22.9 Refrigerant-to-Water Temperature Relationship for Wastewater Systems
517(2)
22.10 Recirculating Water Systems
519(1)
22.11 Cooling Towers
520(1)
22.12 Natural-Draft Towers
520(1)
22.13 Forced- or Induced-Draft Towers
521(2)
22.14 Evaporative Condensers
523(1)
22.15 Air-Cooled Condensers
524(3)
22.16 High-Efficiency Condensers
527(1)
22.17 The Condenser and Low Ambient Conditions
527(3)
22.18 Head Pressure Controls
530(10)
22.19 Using the Condenser Superheat
540(1)
22.20 Heat Reclaim
540(1)
22.21 Floating Head Pressures
540(3)
Unit 23 Compressors
543(35)
23.1 The Function of the Compressor
543(2)
23.2 Types of Compressors
545(5)
23.3 Reciprocating Compressor Components
550(9)
23.4 Belt-Drive Mechanism Characteristics
559(1)
23.5 Direct-Drive Compressor Characteristics
560(1)
23.6 Reciprocating Compressor Efficiency
560(2)
23.7 Discus Valve Design
562(1)
23.8 New Technology in Compressors
563(9)
23.9 Liquid in the Compressor Cylinder
572(2)
23.10 System Maintenance and Compressor Efficiency
574(4)
Unit 24 Expansion Devices
578(27)
24.1 Expansion Devices
578(1)
24.2 Thermostatic Expansion Valve
578(2)
24.3 TXV Components
580(1)
24.4 The Valve Body
581(1)
24.5 The Diaphragm
581(1)
24.6 Needle and Seat
582(2)
24.7 The Spring
584(1)
24.8 The Sensing Bulb and Transmission Tube
585(1)
24.9 Types of Bulb Charge
585(1)
24.10 The Liquid Charge Bulb
585(2)
24.11 The Cross Liquid Charge Bulb
587(1)
24.12 The Vapor (Gas) Charge Bulb
587(1)
24.13 The Cross Vapor Charge Bulb
588(1)
24.14 Example of a TXV Functioning with an Internal Equalizer
588(1)
24.15 TXV Functioning with External Equalizers
589(4)
24.16 TXV Response to Load Changes
593(1)
24.17 TXV Selection
593(1)
24.18 Balanced-Port TXV
593(1)
24.19 The Pressure-Limiting TXV
593(1)
24.20 Servicing the TXV
593(1)
24.21 Installing the Sensing Element
594(1)
24.22 Stepper Motor Expansion Valves
595(2)
24.23 Algorithms and PID Controllers
597(1)
24.24 The Automatic Expansion Valve
598(1)
24.25 Automatic Expansion Valve Response to Load Changes
599(1)
24.26 Special Considerations for the TXV and AXV
600(1)
24.27 The Capillary Tube Metering Device
600(2)
24.28 The Piston Metering Device
602(1)
24.29 Operating Charge for the Fixed-Bore System
602(3)
Unit 25 Special Refrigeration System Components
605(47)
25.1 Introduction to Special Refrigeration System Components
605(1)
25.2 Evaporator Controls
606(4)
25.3 Compressor Controls and Oil-Related Components
610(7)
25.4 Low-Ambient Controls
617(4)
25.5 Pressure Switches and Controls
621(7)
25.6 Solenoid Valves and the Automatic Pumpdown Cycle
628(5)
25.7 Defrost Controls
633(4)
25.8 Refrigeration Accessories
637(7)
25.9 System Valves and Service Access Devices
644(8)
Unit 26 Applications of Refrigeration Systems
652(36)
26.1 Application Decisions
652(1)
26.2 Reach-in Refrigeration
652(4)
26.3 Single-Compressor Applications and Multiple Evaporators
656(3)
26.4 Parallel Compressor Systems
659(8)
26.5 Secondary-Fluid Refrigeration Systems
667(2)
26.6 Carbon Dioxide (R-744) Refrigeration Systems
669(4)
26.7 Pressurized Liquid Systems
673(2)
26.8 Distributed Refrigeration Systems
675(1)
26.9 Evaporator Temperature Control
676(1)
26.10 Interconnecting Piping in Multiple-Evaporator Installations
676(1)
26.11 Fixture Temperature Control
677(1)
26.12 The Evaporator and Merchandising
677(1)
26.13 Chest-Type Refrigeration Fixtures
678(2)
26.14 Controlling Sweating on Fixture Cabinets
680(1)
26.15 Maintaining Store Ambient Conditions
680(1)
26.16 Walk-in Refrigeration
681(2)
26.17 Condensate Removal
683(1)
26.18 Refrigeration Piping
683(1)
26.19 Refrigerated Air Driers
684(4)
Unit 27 Commercial Ice Machines
688(45)
27.1 Packaged-Type Ice-Making Equipment
688(1)
27.2 Making Flake Ice
688(9)
27.3 Making Cube Ice
697(16)
27.4 Microprocessors
713(7)
27.5 Water and Ice Quality
720(4)
27.6 Package Ice Machine Location
724(1)
27.7 Troubleshooting Ice Makers
725(3)
27.8 Service Technician Calls
728(5)
Unit 28 Special Refrigeration Applications
733(19)
28.1 Transport Refrigeration
733(1)
28.2 Truck Refrigeration Systems
733(6)
28.3 Railway Refrigeration
739(2)
28.4 Extra-Low-Temperature Refrigeration
741(2)
28.5 Cascade Systems
743(1)
28.6 Quick-Freezing Methods
743(2)
28.7 Marine Refrigeration
745(5)
28.8 Air Cargo Hauling
750(2)
Unit 29 Troubleshooting and Typical Operating Conditions for Commercial Refrigeration
752(48)
29.1 Organized Troubleshooting
752(1)
29.2 Troubleshooting High-Temperature Applications
753(2)
29.3 Troubleshooting Medium-Temperature Applications
755(1)
29.4 Troubleshooting Low-Temperature Applications
756(1)
29.5 Typical Air-Cooled Condenser Operating Conditions
756(1)
29.6 Calculating the Correct Head Pressure for Air-Cooled Equipment
757(1)
29.7 Typical Operating Conditions for Water-Cooled Equipment
758(3)
29.8 Refrigerant Undercharge
761(1)
29.9 Refrigerant Overcharge
762(2)
29.10 Inefficient Evaporator
764(1)
29.11 Inefficient Condenser
765(2)
29.12 Refrigerant Flow Restrictions
767(3)
29.13 Inefficient Compressor
770(1)
29.14 Compressor Vacuum Test
770(1)
29.15 Closed-Loop Compessor Running Bench Test
771(1)
29.16 Closed-Loop Compressor Running Field Test
772(1)
29.17 Compressor Running Test in the System
773(2)
29.18 Diagnostic Chart for Commercial Refrigeration
775(2)
29.19 Service Technician Calls
777(23)
Section 6: Air-Conditioning (Heating and Humidification)
Unit 30 Electric Heat
800(20)
30.1 Introduction
800(1)
30.2 Portable Electric Heating Devices
800(1)
30.3 Radiant Heating Panels
801(1)
30.4 Electric Baseboard, Unit and Wall Heaters
802(1)
30.5 Electric Hydronic Boilers
803(1)
30.6 Central Forced-Air Electric Furnaces
803(1)
30.7 Automatic Controls for Forced-Air Electric Furnaces
803(3)
30.8 Wiring Diagrams
806(2)
30.9 Control Circuits for Forced-Air Electric Furnaces
808(2)
30.10 Blower Motor Circuits
810(3)
30.11 Airflow in Electric Furnaces
813(2)
30.12 Diagnostic Chart for Electric Heat
815(1)
30.13 Service Technician Calls
816(4)
Unit 31 Gas Heat
820(73)
31.1 Introduction to Gas-Fired, Forced-Hot-Air Furnaces
820(1)
31.2 Types of Furnaces
821(2)
31.3 Gas Fuels
823(2)
31.4 Gas Combustion
825(2)
31.5 Gas Regulators
827(1)
31.6 Gas Valve
828(7)
31.7 Fuel Delivery Components
835(2)
31.8 Heat Exchangers
837(3)
31.9 Fan and Limit Controls
840(3)
31.10 Pilots
843(3)
31.11 Ignition Systems
846(2)
31.12 Flame Rectification
848(4)
31.13 High-Efficiency Gas Furnaces
852(5)
31.14 Electronic Ignition Modules and Integrated Furnace Controllers
857(6)
31.15 Two-Stage and Modulating Gas Furnaces
863(2)
31.16 Venting
865(3)
31.17 Gas Piping
868(2)
31.18 Gas Furnace Wiring Diagrams and Trouble-shooting Flowcharts
870(8)
31.19 Troubleshooting the Safety Pilot-Proving Device-The Thermocouple
878(1)
31.20 Troubleshooting Spark Ignition and Intermittent Pilot Systems
878(3)
31.21 Combustion Efficiency
881(2)
31.22 Preventative Maintenance
883(2)
31.23 Service Technician Calls
885(8)
Unit 32 Oil Heat
893(61)
32.1 Introduction to Oil-Fired, Forced-Warm-Air Furnaces
893(1)
32.2 Physical Characteristics
894(1)
32.3 Fuel Oils
894(3)
32.4 Oil Storage
897(2)
32.5 Fuel Oil Supply Systems
899(5)
32.6 Combustion
904(1)
32.7 Preparation of Fuel Oil for Combustion
905(1)
32.8 By-Products of Combustion
906(1)
32.9 Gun-Type Oil Burners
906(16)
32.10 Oil Furnace Wiring Diagrams
922(5)
32.11 Wiring Diagram for the Stack Switch Safety Control
927(1)
32.12 Wiring Diagram for Cad Cell Primary Control with Intermittent Ignition
928(2)
32.13 Wiring Diagram for Cad Cell Primary Control with Interrupted Ignition
930(1)
32.14 Combustion Chamber
931(2)
32.15 Heat Exchanger
933(4)
32.16 Condensing Oil Furnace
937(1)
32.17 Service Procedures
938(4)
32.18 Combustion Efficiency
942(3)
32.19 Preventive Maintenance
945(1)
32.20 Diagnostic Chart for Oil Heat
946(1)
32.21 Service Technician Calls
947(7)
Unit 33 Hydronic Heat
954(57)
33.1 Introduction to Hydronic Heating
954(1)
33.2 The Heat Source
955(4)
33.3 The Basic Hydronic System
959(6)
33.4 The Point of No Pressure Change
965(1)
33.5 Other Hydronic System Components
966(10)
33.6 High-Temperature Hydronic Piping Systems
976(12)
33.7 Radiant, Low-Temperature Hydronic Piping Systems
988(6)
33.8 Combination (High- and Low-Temperature) Piping Systems
994(1)
33.9 Tankless Domestic Hot Water Heaters
994(1)
33.10 Solar Heating as a Supplemental Heat Source
995(10)
33.11 Preventive Maintenance
1005(1)
33.12 Service Technician Calls
1006(5)
Unit 34 Indoor Air Quality
1011(25)
34.1 Introduction
1011(1)
34.2 Sources of Indoor Air Pollution
1011(2)
34.3 Common Pollutants
1013(4)
34.4 Sick Building Syndrome
1017(1)
34.5 Mold Remediation
1017(1)
34.6 Ventilation
1018(2)
34.7 Air Cleaning
1020(5)
34.8 Duct Cleaning
1025(1)
34.9 Air Humidification
1026(5)
34.10 Diagnostic Chart for Filtration and Humidification Systems
1031(5)
Section 7: Air-Conditioning (Cooling)
Unit 35 Comfort and Psychrometrics
1036(25)
35.1 Comfort
1036(1)
35.2 Food Energy and the Body
1036(1)
35.3 Heat Transfer to and from the Body
1037(1)
35.4 The Comfort Chart
1038(1)
35.5 Psychrometrics
1038(3)
35.6 Absolute and Relative Humidity
1041(1)
35.7 Superheated Gases in Air
1042(1)
35.8 Dry-Bulb and Wet-Bulb Temperatures
1043(1)
35.9 Dew Point Temperature
1044(1)
35.10 Enthalpy
1045(1)
35.11 The Psychrometric Chart
1046(1)
35.12 Plotting on the Psychrometric Chart
1046(3)
35.13 Fresh Air, Infiltration, and Ventilation
1049(12)
Unit 36 Refrigeration Applied to Air-Conditioning
1061(22)
36.1 Air-Conditioning
1061(1)
36.2 Structural Heat Gain
1061(2)
36.3 Evaporative Cooling
1063(1)
36.4 Package-Type and Split-Type Air-Conditioning Systems
1064(3)
36.5 The Evaporator
1067(1)
36.6 Evaporator Coil Configurations
1068(1)
36.7 Design Conditions
1069(2)
36.8 The Compressor
1071(1)
36.9 The Reciprocating Compressor
1071(1)
36.10 Cooling the Compressor and Motor
1072(1)
36.11 The Rotary Compressor
1072(1)
36.12 The Scroll Compressor
1073(2)
36.13 The Condenser
1075(2)
36.14 Expansion Devices
1077(1)
36.15 Air-Side Components
1078(1)
36.16 Installation Procedures
1078(5)
Unit 37 Air Distribution and Balance
1083(51)
37.1 Conditioning Equipment
1083(1)
37.2 Correct Air Quantity
1084(1)
37.3 The Forced-Air System
1084(2)
37.4 The Blower
1086(1)
37.5 System Pressures
1087(1)
37.6 Air-Measuring Instruments for Duct Systems
1088(1)
37.7 Types of Fans and Blowers
1089(3)
37.8 Types of Drive Assemblies
1092(1)
37.9 The Supply Duct System
1093(4)
37.10 Duct Materials
1097(10)
37.11 Duct Air Movement
1107(1)
37.12 Balancing Dampers
1108(1)
37.13 Zoning
1109(3)
37.14 Duct Insulation
1112(1)
37.15 Blending the Conditioned Air with Room Air
1113(1)
37.16 The Return-Air Duct System
1114(1)
37.17 Sizing Duct for Moving Air
1114(4)
37.18 Measuring Air Movement for Balancing
1118(2)
37.19 The Air Friction Chart
1120(6)
37.20 Practical Troubleshooting Techniques
1126(8)
Unit 38 Installation
1134(24)
38.1 Introduction to Equipment Installation
1134(1)
38.2 Installing Square and Rectangular Duct
1134(2)
38.3 Installing Round Metal Duct Systems
1136(1)
38.4 Insulation and Acoustical Lining for Metal Duct
1137(1)
38.5 Installing Ductboard Systems
1137(2)
38.6 Installing Flexible Duct
1139(1)
38.7 Electrical Installation
1139(2)
38.8 Installing Package Systems
1141(4)
38.9 Installing Split-System Air Conditioners
1145(4)
38.10 The Split-System Condensing Unit
1149(1)
38.11 Installing Refrigerant Piping on Split-Systems
1150(4)
38.12 Equipment Start-Up
1154(4)
Unit 39 Residential Energy Auditing
1158(48)
39.1 Introduction
1158(1)
39.2 Residential (Home) Energy Auditing
1159(1)
39.3 Performing a Home Energy Audit
1160(5)
39.4 Diagnostic Testing
1165(1)
39.5 Blower Door Testing
1166(2)
39.6 Infrared Scanning Using a Thermal Imaging Camera
1168(7)
39.7 Sealing Air Leaks
1175(4)
39.8 Duct Leakage Testing
1179(3)
39.9 Duct Pressurization Test for Total Air Leakage
1182(1)
39.10 Duct Leakage to the Outdoors
1183(1)
39.11 Combustion Efficiency and Safety Testing
1184(2)
39.12 Combustion Analysis
1186(2)
39.13 Furnace Efficiency Ratings
1188(1)
39.14 Flame Color
1189(1)
39.15 Spillage and Backdrafting
1189(2)
39.16 Flame Safeguard Controls
1191(1)
39.17 Excess Air
1192(1)
39.18 Venting
1192(3)
39.19 Draft
1195(2)
39.20 High-Efficiency Gas Furnace Design
1197(1)
39.21 HVACR System Testing
1198(1)
39.22 Numerical Analysis and Reporting
1199(7)
Unit 40 Typical Operating Conditions
1206(15)
40.1 Mechanical Operating Conditions
1206(1)
40.2 Relationships of System Components Under Load Changes
1207(1)
40.3 Evaporator Operating Conditions
1207(1)
40.4 High Evaporator Load and a Cool Condenser
1207(3)
40.5 Grades of Equipment
1210(1)
40.6 Documentation with the Unit
1211(1)
40.7 Establishing a Reference Point on Unknown Equipment
1212(1)
40.8 System Pressures and Temperatures for Different Operating Conditions
1213(3)
40.9 Equipment Efficiency Ratings
1216(1)
40.10 Typical Electrical Operating Conditions
1217(1)
40.11 Matching the Unit to the Correct Power Supply
1217(1)
40.12 Starting the Equipment with the Correct Data
1217(1)
40.13 Finding a Point of Reference for an Unknown Motor Rating
1218(1)
40.14 Determining the Compressor Running Amperage
1218(1)
40.15 Compressors Operating at Full-Load Current
1218(1)
40.16 Two-Speed and Variable Speed Compressors
1219(2)
Unit 41 Troubleshooting
1221(33)
41.1 Introduction
1221(1)
41.2 Mechanical Troubleshooting
1221(4)
41.3 Temperature Difference, Temperature Split, and Approach Temperature
1225(1)
41.4 Gauge Manifold Usage
1226(1)
41.5 When to Connect the Gauges
1227(1)
41.6 Low-Side Gauge Readings
1228(1)
41.7 High-Side Gauge Readings
1228(3)
41.8 Temperature Readings
1231(4)
41.9 Charging Procedures in the Field
1235(3)
41.10 Electrical Troubleshooting
1238(1)
41.11 Compressor Overload Problems
1239(1)
41.12 Compressor Electrical Checkup
1240(4)
41.13 Troubleshooting the Circuit Electrical Protectors-Fuses and Breakers
1244(1)
41.14 Diagnostic Chart for Air-Conditioning (Cooling) Systems
1245(1)
41.15 Service Technician Calls
1246(8)
Section 8: All-Weather Systems
Unit 42 Heat Gains and Heat Losses in Structures
1254(19)
42.1 Introduction to Heat Gain and Heat Loss
1254(1)
42.2 Methods to Determine the Heat Gain and Heat Loss of a Structure
1255(1)
42.3 Indoor and Outdoor Design Conditions for Heating and Cooling
1256(1)
42.4 U-Values and R-Values
1257(2)
42.5 Introduction to Heat Gain and Heat Loss Calculations
1259(1)
42.6 Elements of Structural Heat Loss (Heating Mode)
1259(8)
42.7 Elements of Structural Heat Gain (Cooling Mode)
1267(6)
Unit 43 Air Source Heat Pumps
1273(52)
43.1 Reverse-Cycle Refrigeration
1274(1)
43.2 Heat Sources for Winter
1274(1)
43.3 The Four-Way Reversing Valve
1274(5)
43.4 The Air-To-Air Heat Pump
1279(1)
43.5 Refrigerant Line Identification
1280(1)
43.6 Metering Devices
1281(2)
43.7 Liquid-Line Accessories
1283(1)
43.8 Application of the Air-To-Air Heat Pump
1284(3)
43.9 Coefficient of Performance
1287(1)
43.10 The Split-Type, Air-To-Air Heat Pump
1288(3)
43.11 Package Air-To-Air Heat Pumps
1291(1)
43.12 Controls for the Air-To-Air Heat Pump
1292(7)
43.13 The Defrost Cycle
1299(4)
43.14 Second-Stage Electric Heat
1303(1)
43.15 Servicing the Air-To-Air Heat Pump
1304(1)
43.16 Troubleshooting the Electrical System
1304(2)
43.17 Troubleshooting Mechanical Problems
1306(1)
43.18 Troubleshooting the Four-Way Reversing Valve
1306(1)
43.19 Troubleshooting the Compressor
1307(1)
43.20 Checking the Charge
1307(2)
43.21 Special Applications for Heat Pumps
1309(1)
43.22 Heat Pumps Using Scroll Compressors
1310(1)
43.23 Heat Pump Systems with Variable-Speed Motors
1311(1)
43.24 Preventive Maintenance
1312(1)
43.25 Diagnostic Chart for Heat Pumps in the Heating Mode
1313(1)
43.26 Service Technician Calls
1314(11)
Unit 44 Geothermal Heat Pumps
1325(35)
44.1 Reverse-Cycle Refrigeration
1325(1)
44.2 Geothermal Heat Pump Classifications
1325(1)
44.3 Open-Loop Systems
1326(1)
44.4 Water Quality
1327(1)
44.5 Closed-Loop Systems
1328(5)
44.6 Ground-Loop Configurations and Flows
1333(2)
44.7 System Materials and Heat Exchange Fluids
1335(1)
44.8 Geothermal Wells and Water Sources for Open-Loop Systems
1336(3)
44.9 Water-To-Water Heat Pumps
1339(1)
44.10 Troubleshooting
1340(3)
44.11 Direct Geothermal Heat Pump Systems
1343(10)
44.12 Service Technician Calls
1353(7)
Section 9: Domestic Appliances
Unit 45 Domestic Refrigerators and Freezers
1360(61)
45.1 Refrigeration
1360(8)
45.2 Capacity of Domestic Systems
1368(1)
45.3 The Evaporator
1369(3)
45.4 The Compressor
1372(2)
45.5 The Condenser
1374(4)
45.6 Metering Device
1378(2)
45.7 Typical Operating Conditions
1380(2)
45.8 Ice-Maker Operation
1382(1)
45.9 Wiring and Controls
1383(9)
45.10 Servicing the Appliance
1392(15)
45.11 Service Technician Calls
1407(14)
Unit 46 Room Air Conditioners
1421(31)
46.1 Air-Conditioning and Heating with Room Units
1421(1)
46.2 Room Air-Conditioning-Cooling
1422(1)
46.3 The Refrigeration Cycle-Cooling
1422(4)
46.4 Heat-Pump-Style Room Units
1426(3)
46.5 Installation
1429(5)
46.6 Controls for Cooling-Only Room Units
1434(3)
46.7 Controls in Cooling and Heating Units
1437(1)
46.8 Maintaining and Servicing Room Units
1437(7)
46.9 Service Technician Calls
1444(8)
Section 10: Commercial Air-Conditioning and Chilled-Water Systems
Unit 47 High-Pressure, Low-Pressure, and Absorption Chilled-Water Systems
1452(46)
47.1 Introduction to Chilled-Water Systems
1452(2)
47.2 Compression Cycle in High-Pressure Chillers
1454(1)
47.3 Reciprocating Compressors in High-Pressure Chillers
1454(2)
47.4 Scroll Compressors in High-Pressure Chillers
1456(1)
47.5 Rotary Screw Compressors in High-Pressure Chillers
1457(1)
47.6 Centrifugal Compressors in High-Pressure Chillers
1458(4)
47.7 Evaporators for High-Pressure Chillers
1462(4)
47.8 Condensers for High-Pressure Chillers
1466(4)
47.9 Metering Devices for High-Pressure Chillers
1470(2)
47.10 Low-Pressure Chillers
1472(3)
47.11 Absorption Air-Conditioning Chillers
1475(11)
47.12 Motors and Drives for Chillers
1486(12)
Unit 48 Cooling Towers and Pumps
1498(29)
48.1 Cooling Tower Function
1498(2)
48.2 Types of Cooling Towers
1500(3)
48.3 Fire Protection
1503(1)
48.4 Fill Material
1504(1)
48.5 Flow Patterns
1504(2)
48.6 Tower Materials
1506(1)
48.7 Fan Section
1506(1)
48.8 Tower Access
1507(1)
48.9 Tower Sump
1508(1)
48.10 Makeup Water
1509(1)
48.11 Blowdown
1510(2)
48.12 Balancing the Water Flow in a Cooling Tower
1512(1)
48.13 Water Pumps
1512(8)
48.14 Chemical-Free Treatment of Cooling Tower Water
1520(7)
Unit 49 Operation, Maintenance, and Troubleshooting of Chilled-Water Air-Conditioning Systems
1527(27)
49.1 Chiller Start-Up
1527(6)
49.2 Valves for Large Systems
1533(3)
49.3 Scroll and Reciprocating Chiller Operation
1536(1)
49.4 Large Positive-Displacement Chiller Operation
1537(1)
49.5 Centrifugal Chiller Operation
1537(1)
49.6 Air-Cooled Chiller Maintenance
1537(2)
49.7 Water-Cooled Chiller Maintenance
1539(3)
49.8 Absorption Chilled-Water System Start-Up
1542(1)
49.9 Absorption Chiller Operation and Maintenance
1543(1)
49.10 General Maintenance for All Chillers
1544(1)
49.11 Low-Pressure Chillers
1544(2)
49.12 High-Pressure Chillers
1546(1)
49.13 Refrigerant Safety
1546(1)
49.14 Service Technician Calls
1546(8)
Unit 50 Commercial, Packaged Rooftop, Variable Refrigerant Flow, and Variable Air Volume Systems
1554(49)
50.1 Rooftop Package Units
1555(2)
50.2 Installation of Packaged Rooftop Units
1557(6)
50.3 Economizers
1563(2)
50.4 Economizer Modes of Operation
1565(4)
50.5 ASHRAE Standard 62
1569(1)
50.6 Demand Control Ventilation (DCV)
1570(1)
50.7 Traditional Constant-Volume Air Distribution Methods
1571(1)
50.8 Variable Air Volume (VAV) Systems
1571(1)
50.9 VAV Boxes and Terminal Units
1572(2)
50.10 Hot Water in the Reheat Coils
1574(1)
50.11 Chilled-Water VAV Systems
1575(5)
50.12 Variable Refrigerant Flow (VRF) Systems
1580(13)
50.13 Dry Coolers
1593(4)
50.14 Chilled Beam Systems
1597(6)
Appendix A Alternative Heating (Stoves and Fireplace Inserts) 1603(9)
A.1 Wood-Burning Stoves
1603(1)
A.2 Organic Makeup and Characteristics of Wood
1603(1)
A.3 Environmental Protection Agency (EPA) Regulations
1604(1)
A.4 Creosote
1604(1)
A.5 Design Characteristics of Wood-Burning Stoves
1604(4)
A.6 Installation Procedures
1608(1)
A.7 Smoke Detectors
1609(1)
A.8 Gas Stoves
1610(1)
A.9 Fireplace Inserts
1610(2)
Appendix B Temperature Conversion Chart 1612(2)
Glossary/Glosario 1614(52)
Index 1666
Since entering the HVAC industry in 1980, Eugene has taken on many roles ranging from field technician and system designer to company owner, teacher, administrator, consultant, college professor and author. With 30 years of teaching experience, Eugene is currently the National Programs Director at HVAC Excellence and has taught air conditioning and refrigeration at many high school vocational programs, proprietary post-secondary institutions and community colleges. Eugene retired from his tenured teaching position at Suffolk County Community College in Brentwood, New York, to join the ESCO Group, and earned his dual Bachelors Degree from The City College of New York (New York, NY) and his Masters of Science degree from Stony Brook University (Stony Brook, NY), where he specialized in Energy and Environmental Systems, studying renewable and sustainable energy sources such as wind, solar, geothermal, biomass and hydropower. He earned his Certified Master HVAC/R Educator (CMHE) credential from HVAC Excellence and the ESCO Group in 2010. Eugene also carries ASHRAEs BEAP credential, which classifies him as a Building Energy Assessment Professional. He is also an active member of many industry societies and has served as the subject matter expert on a multitude of HVAC-related educational projects. His most notable work is Cengage Learnings REFRIGERATION & AIR CONDITIONING TECHNOLOGY, which is now, with this printing, entering its 10th Edition (2025). This book is used in more than 1,000 schools, both in this country and abroad, to help individuals master the skills they need to install, service, troubleshoot and design HVACR equipment. In 2002, Jason Obrzut graduated from the HVAC Technical Institute in Chicago, kick-starting an accomplished career in the HVAC Industry. Jason began working as a service technician, became an installation supervisor and ultimately a business owner. While working during the day, he returned to the HVAC Technical Institute as a part-time, evening instructor. Teaching quickly became his passion and he scaled back on working in the field to focus on teaching full time. While teaching, Jason developed, wrote and implemented the curriculum that is currently being taught at the school. His dedication to his students and the institution was evident and he soon became the schools Director of Education and lead HVAC/R instructor. In 2016, The ACHR News recognized Jason as one of the Top 40 Under 40 in the HVAC industry. He is affiliated with numerous HVAC industry organizations, including Refrigeration Service Engineers Society (RSES), The Air Conditioning, Heating, and Refrigeration Institute (AHRI), the ESCO Group and HVAC Excellence. Jason served on AHRIs Safe Refrigerant Transition Taskforce (SRTTF) as chairman of the technician outreach committee. At HVAC Excellences 2016 National HVAC Educators and Trainers Conference (NHETC), Jason participated in the first annual Teachers-N-Trainers (TnT) competition and took first place in a field of over 60 participants. Jason is one of only 125 instructors nationwide who have held the title of Certified Master HVAC/R Educator (CMHE), and he holds Certified Subject Matter Educator (CSME) certificates from the ESCO Group. John Tomczyk received his associate degree in refrigeration, heating and air-conditioning technology from Ferris State University in Big Rapids, Michigan, his bachelors degree in mechanical engineering from Michigan State University in East Lansing, Michigan and his masters degree in education from Ferris State University. Mr. Tomczyk has worked in refrigeration, heating, air conditioning service and technical writing consultation for both the academic and industrial fields for numerous years, enabling him to bring a wealth of experience to this text. His technical articles have been featured in many HVACR magazines and journals. Mr. Tomczyk is also the author of TROUBLESHOOTING AND SERVICING MODERN AIR CONDITIONING AND REFRIGERATION SYSTEMS. Mr. Tomczyk has 29 years of teaching experience at the Refrigeration, Heating and Air-Conditioning Technology program at Ferris State University and is a member of many HVAC/R trade organizations. Bill Whitman contributed a wealth of academic expertise as well as industry knowledge to this book. Mr. Whitman graduated from Keene State College in Keene, New Hampshire with a bachelors degree in Industrial Education. He received his masters degree in School Administration from St. Michaels College in Winooski, Vermont. After instructing drafting courses for three years, Mr. Whitman became the Director of Vocational Education for the Burlington Public Schools in Burlington, Vermont, a position he held for eight years. He spent five years as the Associate Director of Trident Technical College in Charleston, South Carolina. Mr. Whitman was the head of the Department of Industry for Central Piedmont Community College in Charlotte, North Carolina, for 18 years. Bill Johnson taught heating, air conditioning and refrigeration for more than two decades in various technical colleges and factory schools. A graduate of Southern Technical Institute, a branch of Georgia Tech in Atlanta, he also served as service manager for a major manufacturer for six years. Mr. Johnson owned his own HVAC/R business for 10 years and was a member of the Refrigeration Service Engineers Society and the American Society of Heating Refrigerating Air Conditioning Engineers. His authoring credits include three major textbooks on the market today as well as their ancillary materials. He has also written monthly articles, BTU Buddy, that are available online.