Today's Technician: Heating & Air Conditioning, 4E is a two-book set that separates theory and diagnostic content into Classroom and Shop Manuals. This separation allows readers to learn theories of heating and air conditioning before applying them, with the benefit of cross-referenced page numbers in each manual to link related material. Updated to reflect the industry's latest developments and trends, this edition includes expanded coverage of basic theories, as well as all-new sections on upgraded equipment, sealant contamination and testing, and non-compressible gas contamination. In addition, the information on compressors has been updated to include new hybrid electric compressors and the safety issues that accompany them. With this up-to-date, technically accurate information, this is a valuable resource for learning the theory, components, diagnosis and repair of modern automotive heating and air conditioning systems.