Basic information on electrical equipment, control circuits, control and protection devices of general-purpose air conditioners, which are widely used in various industries, public and civil buildings and structures. Considered are autonomous air conditioners with built-in refrigerating machines and non-autonomous central and aggregate air conditioners powered by heat and cold from external centralized sources. The book is intended for electricians who have to maintain air conditioners, and can be useful for students of vocational schools, technical schools and young specialists of relevant specialties.