Preface Heating and Cooling Essentials provides a thorough, easily understood, and up-to-date textbook for persons entering the refrigeration, heating, and air conditioning field. The text is a practical blend of theory, on-the-job skills-building procedures, and customer service soft-skill training. It is designed for use by first-year students in HVACR programs at career centers, technical schools, adult continuing education classes, or community colleges. This text may also be used in apprenticeship programs and can serve as an excellent reference for working technicians. Heating and Cooling Essentials is written from a service technician’s point of view, but the service experience is appropriate for the HVACR student. Being able to combine on-the-job skills with theory is a must to become a successful service technician. The content of the textbook provides a solid foundation in the basics and integrates prac- tical service procedures with technical theory. The book is a complete and accurate guide to trouble- shooting and performing essential service proce- dures on many types of systems. An important aspect of Heating and Cooling Essentials is its emphasis on career information and workplace skills. A chapter covers an over- view of the HVACR industry, explains why HVACR is a good career option, and discusses different career paths in the HVACR industry. Also discussed are some of the physical, mental, communication, and technical skills needed to be successful in HVACR. A textbook is not a storybook that is read only once. It is designed to be read over and over again. Just because you master a chapter today does not mean that you will remember every- thing about that chapter later in your training or even when you enter the workforce. Refresh your knowledge by rereading chapters already covered even after finishing your education. This textbook will provide you with a sound foundation for further study of more specialized aspects of the HVACR field. Remember that to be a success means not only mastering your hands- on-skills, but also understanding operational theory and having great customer soft skills. Heating and Cooling Essentials aligns with curriculum standards for HVAC Excellence and PAHRA accreditation. iii