Table of Contents

Chapter 1:

Introduction to Automotive Heating, Air

Conditioning, and Ventilation 11

Heating, Ventilating, and Air Conditioning(HVAC) Systems 12

Why Is It Called HVAC?

Major Heating, Ventilation, and Air ConditioningSystem Components 12

Refrigeration System Parts and Operation / Heating

System Parts and Operation / Air Delivery SystemParts and Operation

HVAC System Controls 19

Mechanical Devices

HVAC System Operation 20

Air Conditioning / Ventilating / Heating / Defrost

HVAC System History 21

Heaters / Ventilation / Air ConditioningThe Air Conditioner and the Ozone Layer 23

Chapter 2:

Shop Safety and Environmental

Protection 27

Causes of Accidents 28

Personal Safety Equipment 28

Proper Clothing and Protective Equipment / EyeProtection / Foot and Hand Protection

Kinds of Accidents 29

Maintaining a Safe Workplace / Performing WorkProcedures Properly

Refrigerant Safety Precautions 34

Vapor and Liquid Refrigerants / Rules for HandlingRefrigerants

First Aid for Refrigerant Exposure 35

First Aid for Skin Exposure / First Aid for Eye

Exposure / First Aid for Breathing Difficulty

Preventing Environmental Damage 35

Prevent Solid Waste Contamination / Prevent LiquidWaste Contamination / Prevent Gaseous Waste

Contamination / The Environmental Protection

Agency

Chapter 3:

HVAC Tools, Equipment, and

Service Information 39

Diagnostic and Test Equipment 40

Gauge Manifolds / Temperature Gauges / Leak

Detectors / Refrigerant Identifiers / Electrical Test

Equipment / Belt Tension Gauges / Vacuum Pumps/Gauges

HVAC System Service Tools 47

Compressor Service Tools / Compressor Clutch

Service Tools / Hose Tools / Orifice Tube Tools / Oil

Injectors

Refrigerant Service Equipment 51

Recovery/Recycling Equipment/Flushing Equipment/Evacuation Pumps / Recharging Equipment / Air

Purging Equipment

Engine Cooling System Test Equipment 54

Pressure and Leak Testers / Antifreeze Testers /Combustion Leak Testers

Vehicle Protection 56

Service Information 57

Factory Manual / General Manual / Specialized Manual /Technical Service Bulletins/Telephone Hotlines/

Internet Resources

Table of Contents 7

Chapter 4:

HVAC Electrical and Electronic Fundamentals.. 63

Electrical Basics 64

Conductors and Insulators / Electrical Measurements /'

Direct and Alternating Current / Types of Electrical

Circuits / Circuit Defects

Electromagnetism 67

Vehicle Wiring and Electrical Components 68

Wiring / Wiring Schematics / Circuit Protection

Devices / Switches / Solenoids, Relays, and MagneticClutches / Motors / Resistors / Capacitors

Basic Electrical Diagnosis 75

Electrical Device Not Working / Electrical Device on

at All Times

Vehicle Computers 75

Semiconductor Materials / Computer Circuits /

Control Loops / Main Computer Sections / Computer

Diagnostic Outputs

Chapter 5:

Principles of Refrigeration 81

The Purpose of Refrigeration 82

Basic Principles of Refrigeration 82

Heat and Cold / Heat Transfer / Change of State /Sensible and Latent Heat/The Pressure-TemperatureRelationship

Refrigeration Components 85

The Two Main Types of Refrigeration Systems /

Evaporator / Accumulator / Compressor / Muffler /Condenser / Receiver-drier / Filter / Sight Glass /Flow Restrictor / Connecting Lines / Service Fittings /

Seals and Gaskets / Which Parts Are Used on Which

Systems? / RefrigerantsThe Refrigeration Cycle 91

Cooling Phase—Evaporator / Pressure Increase

Phase—Compressor / Heat Transfer Phase—

Condenser / Pressure Decrease Phase—Flow

Restrictor / Factors That Affect System Performance

Chapter 6:

Refrigerants, Refrigerant Oils, and Related

Chemicals 97

Refrigerant Purposes 98

Refrigerants and Governmental Regulation 98

Montreal Protocol / Clean Air Act

Types of Refrigerants 99

R-134a / R-12 (Freon) / R-134a versus R-12

Refrigerant Classification 101

Blended Refrigerants (Azeotropic and ZeotropicBlends) / Drop-in Refrigerants / New Refigerants

Replacement Refrigerants 102

Choosing a Replacement Refrigerant / SNAP Program

Refrigerant Oils 104

Types of Refrigerant Oil

Other Refrigeration System Chemicals 105

Desiccants / Flushing Compounds / Leak Detector

Dyes / Evaporator Surface Cleaners / RefrigerationSystem Sealers

Chapter 7:

Hoses, Lines, Fittings, and Seals 109

Hoses and Lines 110

Hoses / Metal Lines / Combination Hose and Line

Assemblies / Hose and Line Attachments / Hose and

Line Size Specifications

Refrigeration System Fittings 112

Compression Fittings / Crimp Fittings / Spring Lock

Couplings / Screw Type Hose Clamps / Service

Fittings

Making Hoses, Lines, and Fittings 116

Refrigeration Sealing Devices 116

Compressor Shaft Seals / O-ring Seals / SealingWashers / Gaskets

Chapter 8:

Compressors, Clutches, and Drives 121

Compressor Purposes 122

Basic Compressor Parts 122

Types of Compressors 122

Piston Compressors / Rotary Vane Compressors /Scroll Compressors

Compressor Capacity Control Valves 130

Compressor Drives and Clutches 130

Compressor Drive / Compressor Clutches /

Compressor Clutch Control Systems / ConstantlyEngaged Compressor Clutch

Compressor Makes and Models 135

Bosch / Calsonic / Chrysler / Frigidaire/Harrison/Delco Air/Delphi / Ford / Hitachi / Keihin /

Matsushita/Panasonic / Mitsubishi / Nihon/Nihon

Radiator / Nippondenso / Sanden/Sankyo / Seiko-

Seki / Seltec / Tecumseh/York / Unicla / Zexel/Diesel

Kiki / Older Compressors

Chapter 9:

Evaporators, Condensers, Accumulators, and

Receiver-Driers 143

Evaporators 144

Evaporator Design and Construction / Types of

Evaporators / Parts Attached to the EvaporatorCondensers 146

Condenser DesignAccumulators 148

Accumulator OperationReceiver-Driers 148

Desiccants

Pressure Relief Devices 150

8Auto Heating & Air Conditioning

Chapter 10:

Control Valves and Switches 153

Two Ways to Control Evaporator Temperature 154

Thermostatic Expansion Valves 154

Equalizers and Springs / H-blocks

Fixed Orifice Tubes 156

Electronic Expansion Valves 156

Evaporator Pressure Controls 157

Types of Evaporator Pressure Controls

Compressor Clutch Controls 161

Pressure Cycling Switches / Thermostatic

Temperature Cycling Switches / Pressure and

Temperature Sensors

System Protection Switches and Valves 163

Pressure Cutoff Switches / Temperature Cutoff

Switches / Thermal Limiters

Chapter 11:

Engine Cooling Systems and

Vehicle Heaters 167

Cooling System 168

Engine Cooling System Operation 168

Engine Cooling System Components 168

Liquid-cooled Engines 168

Coolants / Engine Water Jackets / Coolant Pump /

Coolant Pump Drive Belts / Radiator / Radiator Fans /Thermostat / Coolant Hoses / Pressure Cap / Coolant

Recovery Systems / Drains and Air Bleeds

Air-Cooled Engines 178

Engine Cooling Fins / Blower / Shrouds / Oil Cooler /Thermostat

Heating System 179

Heater—Liquid-Cooled Engine / Heater—Air-Cooled

Engine

Heating System Components 180

Liquid-Cooled System / Air-Cooled System

Chapter 12:

Air Delivery Systems 185

Air Handling Systems 186

Blowers and Motors 186

Blower Wheels / Blower Motors

Air Ducts and Heater/Evaporator Cases 187

Intake Ductwork / Heater and Evaporator Cases /

Output Ductwork / Vents / Independent Vents

Air Doors and Operating Devices 190

Blend Door / Diverter Doors / Door OperatingDevices/Cabin Filters

Chapter 13:

Manual HVAC Controls 199

Control System Purposes 200

Temperature Control / Humidity Control / Airflow

HVAC Control System Modes 200

Manual Control Systems 203

Control System Parts / Electrical and Electronic Controls

/ Compressor Controls / HVAC Electrical SystemProtection Devices / Control System Operation

Chapter 14:

Automatic Temperature Control Systems ..213

Automatic Control Systems 214

Types of Controls / Temperature Control LoopsElectronic Temperature Control Systems 215

Automatic and Semiautomatic Control Heads /

Control System Parts / Control System Operation /

Computer Self-diagnosisOlder Temperature Control Systems 223

Mechanical Temperature Control Systems/Electromechanical Temperature Control Systems

Chapter 15:

Refrigeration System Diagnosis and Leak

Detection 227

Strategy-based Diagnostics 228

The Importance of Proceeding Logically 228

The Seven-Step Troubleshooting Procedure 228

Step 1—Determine the Exact Problem 228

Talking to the Driver

Step 2—Check for Obvious Problems 232

Step 3—Determine Which System Is Causing theProblem 233

Functional and Performance Tests / Leak Detection

Step 4—Eliminate Other Causes of the Problem 243

Step 5—Recheck the Cause of the Problem 243

Always Perform Additional Tests / Deciding on

Needed Work

Step 6—Correct the Defect 246

Step 7—Recheck System Operation 246

Follow-up 246

Documentation of Repairs

Chapter 16:

Refrigerant Recovery, Recycling, and

Handling 251

Refrigerant Service 252

Rules for Handling Refrigerants / Using a RefrigerantIdentifier / Adding Refrigerant to a Partially ChargedSystem

Recovering Refrigerant 254

Recovering R-134a or R-12 / Recovering Blends and

Contaminated Refrigerant / Recycling RefrigerantEvacuating Refrigeration Systems 257

Evacuation Procedure

Flushing Refrigeration Systems 258

Open Loop Flushing / Closed Loop Flushing

Table of Contents 9

Checking and Adding Oil 259

Checking Compressor Oil Level / Adding Oil to

a Charged System / Adding Oil to ReplacementComponents / Adding Oil to the Compressor

Vacuum and Pressure Testing RefrigerationSystems 261

Vacuum Testing / Nitrogen Pressure Testing

Recharging Refrigeration Systems 262

Recharging with Refrigerant Service Center/

Charging with Gauge Manifold / Refrigeration

System Purging

Installing an Inline Filter 264

Maintaining Refrigerant Service Centers 264

Replacing the Filter-Drier / Calibrating the Service

Center's Scale / Changing the Vacuum Pump Oil /

Checking for Leaks / Installing a New Tank / AddingRefrigerant from a Disposable Tank / Removing Air

from Charging Cylinders

Chapter 17:

Hose, Line, Fitting, and O-ring Service.... 269

Servicing Fittings and O-rings 270

Compression Fittings / O-ring Replacement / SpringLock Couplings / Service Fittings

Servicing Hose Fittings 273

Crimped Fittings / Hose ClampsGasket Replacement 274

Hose Service 274

Hose Removal and ReplacementMaking Hoses 274

Selecting Proper Hoses / Installing and CrimpingHose Fittings

Line Service 276

Line Removal and Replacement / Making Lines

Chapter 18:

Compressor and Clutch Service 279

Common Compressor and Clutch Problems 280

Noises / Compressor Clutch Not Engaging /Excessive Pressure / Constant Low Pressure /Occasional Low Pressure

Compressor Removal and Replacement 282

Compressor Removal / Adding Oil to Compressors /

Compressor Installation / Compressor Retrofitting

Compressor Clutch and Electromagnet Service 284

Clutch Removal / Electromagnet and Clutch

Replacement

Compressor Overhaul 287

Shaft Seal Replacement / Rebuilding Compressors /

Overhauling Radial Piston Compressors/Overhauling Axial Piston Compressors / Overhauling

Scroll Compressors / Capacity Control Valve

Removal and Replacement / Replacing Other

Compressor Components

Overhauling Older Compressors 294

Chapter 19:

Valve, Evaporator, Condenser, and Related

Parts Service 297

Common Problems 298

Expansion Valve Failures / Orifice Tubes / EvaporatorPressure Control Valves / Compressor CyclingSwitches / Evaporator / Condenser / Accumulator /Receiver-Drier

Component Service 301

Expansion Valves / Evaporator Pressure Control

Valves / Orifice Tubes / Compressor CyclingSwitches

Evaporators 303

Evaporator Cleaning / Evaporator Replacement /

Afterblow Module Installation

Condensers 307

Condenser Cleaning / Condenser ReplacementAccumulators 307

Replacement Guidelines/ Accumulator ReplacementReceiver-Driers 309

Replacement Guidelines / Receiver-Drier

Replacement

Systems with Multiple Component Units 309

Chapter 20:

Heater and Engine Cooling SystemService 313

Safety Considerations 314

Cooling System Inspection 314

Cooling System Checks

Heating System Problems 320

Poor or No Heating / Too Much Heat / Coolant

Leaks / Heater Problems—Air-cooled Engine

Engine Cooling System Problems 322

Overheating / Coolant Leaks / Causes of Air-cooled

Engine Overheating / OvercoolingHeater Service 323

Changing Heater Hoses and Shutoff Valves /

Changing Heater Cores

Liquid Cooling System Service 327

Changing Coolant and Flushing the CoolingSystem / Belt and Hose Replacement / Thermostat

Replacement / Cooling Fan Replacement / Coolant

Pump Replacement / Radiator ReplacementAir Cooling System Service 333

Cleaning Fins on an Air-cooled Engine / ReplacingBlower Belt / Replacing Blower and Bearing /

Replacing Thermostat

10 Auto Heating & Air Conditioning

Chapter 21:

Air Delivery and Manual HVAC Control

Service 337

Air Delivery and Manual Control System Problems 338

Blower Motors and Related Parts / Cabin Filter/AirIntake Filter / Ducts and Air Doors / Manual Control

Panels

Air Delivery and Control System Service 342

Blend Door Cable Adjustments / Removal and

Replacement of Components / Checking Afterblow

Modules

Chapter 22:

Automatic Temperature Control

System Service 353

Automatic Temperature Control System Problems 354

Electronic Temperature Control Systems / Electronic

Control System Self-DiagnosisElectronic Temperature Control System Testing 359

Testing Input Sensors / Testing Output Devices /

Mechanical Temperature Control Systems /Electromechanical Temperature Control Systems

Electronic Temperature Control System Service 360

Computer Reprogramming/Control Head/

Temperature Control Computer / Air Temperatureand Sunload Sensors / Replacing Output Devices

Mechanical and Electromechanical System Service 364

Adjusting Transducer Cables / Replacing SystemParts / Power Servo / Amplifiers

Chapter 23:

Air Conditioning System Installation and

Retrofitting 367

Aftermarket Air Conditioners 368

Aftermarket Air Conditioning Kits / AftermarketAir Conditioning Considerations / Installing anAftermarket Air Conditioner

R-12 to R-134a Retrofitting 375

Whether to Retrofit / Level of Retrofit / Performing a

Complete Retrofit

Chapter 24:

ASE Certification 383ASE Tests 384

Other ASE Activities/ASE Test Windows

Applying for the ASE Tests 385

Taking the ASE Tests 385

Types of ASE Test Questions 387

One-part Questions/Two-part Questions/NegativeQuestions/Incomplete Sentence Questions

Test Results 388

Technician Confidentiality 388

Recertification Tests 388

Certification in Refrigerant Recovery and

Recycling 388

Chapter 25:

Career Preparation 393

Automotive Servicing 394

Levels of Automotive Service Positions 394

Helpers / Apprentices / Certified Technicians

Types of Auto Service Facilities 395

New Vehicle Dealers / Chain and Department Store

Auto Service Centers / Tire, Muffler, and Other

Specialty Shops / Independent Repair Shops / Fleet

Agencies / Government Agencies / Self-EmploymentOther Opportunities in the Auto Service

Industry 398

Shop Supervisor or Service Manager / Salesperson or

Service Advisor / Parts Person

Getting a Job 399

Finding Job Openings / Applying for the Job

Appendix A:

Rear Window and Mirror Defrosters 403

Defroster Components and Operation 404

Defroster Operation / Older Rear Window DefoggersDefroster Diagnosis 405

Defroster Service 406

Replacing Switches and Relays / Repairing theWindow Grid

Useful Tables 411

Acknowledgments 414

Glossary 415

Index 425