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Electricity for Refrigeration, Heating and Air Conditioning

The heating, ventilation, air conditioning and refrigeration (HVAC/R) industry is a rapidly evolving and changing field. Changes and upgrades in technology is a constant factor that today’s HVAC/R technicians must face. Over the past three decades, we have seen HVAC/R thermostats and control systems transition from primarily electro-mechanical controls to solid-state analog controls, and now, advanced variable-speed systems using communicating and, in some cases, wireless control systems. In the past, the air conditioning equipment used to condition residential homes was primarily composed of single-stage, unitary equipment. Today, it is common to find multi and variable speed equipment and mini-split systems used to condition residential dwellings. There have also been many advances made in electric motor technology over the past 20 years. This course will address the following technological advancements in Electricity for Refrigeration, Heating, and Air Conditioning:

  1. The section on thermostats has been improved and expanded to include more information and graphics on electronic and communicating thermostats.

  2. Some of the wiring diagrams and schematics have been updated or replaced to better reflect modern control systems.

  3. The section on ECM motors has been updated and expanded to now include information and graphics on constant torque (X-13) motors.

  4. The section on mini-split and ductless heating and cooling systems has been updated and expanded.

  5. The chapter on residential air conditioning systems has been heavily updated to include new and additional information and graphics.

  6. Additional information and graphics on troubleshooting control devices and system has been added to multiple sections of the text.

  7. Extensive updates and additions have been made to the art to reflect electrical devices and systems presently used in the industry.

  8. Additional practice service calls have been added to applicable chapters.

Today’s technicians face the difficult task of having to service, troubleshoot and repair many older systems using older mechanical and analog control technology, while at the same time, technicians must also install, service, troubleshoot and repair new equipment using advanced, sophisticated control systems. Technicians must also stay up-to-date as technological advancements are being made and introduced to the HVAC/R industry each day. This text is written with a blend of theory and practicality suitable for vocational/technical or technical and community college students, as well as for industry practitioners who wish to upgrade their knowledge and skills. The purpose of this text is to assemble concepts and procedures that will enable readers to work successfully in the HVAC/R industry.

Features of This Course

The features of this text are designed to enhance the learning experience:

    • A chapter on Electrical Safety provides students with an awareness of the dangers of working with electricity, while Caution notes integrated throughout the chapters explain how to prevent and avoid accidents on the job.

    • Examples walk students through important math equations and calculations essential to understanding how refrigeration, heating, and air-conditioning systems work.

    • Green Technology features information relative to practices that technicians can implement to protect the environment and ultimately the health and safety of the communities they serve.

    • Service Calls reinforce procedures that are commonly used in the industry, while Review Questions and Practice Service Calls provide students with the opportunity to evaluate what they have learned and hone their troubleshooting skills.

    • Delmar Online Training Simulation: HVAC 4.0 references are integrated throughout the text as helpful tools for those classrooms utilizing this enhanced supplement to the text. 

    • Appendix A and Appendix B provide reference charts to review various types of motors, as well as to study electrical symbols commonly used in schematics, including switches, thermostats, contactors, relays, and other electrical devices.

New in This Course Edition

New technology has brought about rapid changes in the thermostats and control systems used in the heating and air-conditioning industry. As a result, this has prompted the following changes for this edition:

  • Due to the rapid change in the design, technology, and availability of electronic thermostats, the thermostat section has been heavily revised and expanded while removing some of the material on the older thermostats and focusing on the more advanced digital, communicating, and wi-fi thermostats.

  • The section on DC motors and controls has been updated and expanded because of their use in unitary and mini-split heating and cooling systems.

  • The section on mini-split air conditioning and heat pump systems has been updated and expanded.

  • Many new and updated art, graphics, and diagram changes and additions have been made to reflect recent changes in technology.

  • New illustrated examples of troubleshooting procedures for control devices and systems have been added to applicable chapters.