Electricity and Electronics for HVAC By Rex Miller and Mark R. Miller

Electricity and Electronics for HVAC By Rex Miller and Mark R. Miller

Preface:
This book is intended to provide an introduction to the basic principles of electricity and electronics as they apply to refrigeration, heating, and air conditioning systems. It combines basic principles, using very little math, with the latest applications found in the HVAC industry. The fields of refrigeration, air conditioning, and heating are undergoing some very rapid changes. The advent of the computer chip has made it possible to control heating and cooling systems precisely and with a great deal of freedom in programming their applications. The new high-efficiency furnaces utilize the chip both for sequencing and for protection from accidental damage. Most of these programmable controllers provide instructions and technical bulletins. They are numerous, and each has its own approach to solving a given problem. This book will make it possible for you to understand these instructions and improvements. Future technicians need to deal with the fact that change is inevitable, and that they will have to keep up with the latest developments as long as they work in the field. It is hoped that this book will make that task easier Introduction to Electricity Electricity is as old as the universe. But knowledge about it is relatively new.Early humans were aware of electricity in the form of lightning. They learnedof its power when they saw it starts fires and kills people and animals. But it was only about 300 years ago that people began to learn the basic laws of electricity. And only about 120 years have passed since electricity was first put to work. It has been only 100 years since the first practical electric lamp was invented, only 80 years since the vacuum tube was invented, and  less than 40 years sincethe transistor was invented. Despite this brief time, electricity has greatly changed people’s lives—our lives. The universe consists of atoms and every atom contains at least one electron. An electron is the smallest particle of an atom and has a negative electric charge. When the movement of electrons is controlled, they are capable of doing work.