This module is the tenth in a series of eleven modules in an energy conservation curriculum for secondary and postsecondary vocational students. It is designed for use by itself or as part of a sequence of four modules on energy conservation in building construction and operation (see also modules 8, 9, and 11). The objective of this module is to train students in the recognition, implementation, and utilization of energy consumption and possible conservation in heating, ventilating, and air conditioning. First, an introduction to the module and definitions of key terms are provided. Next, the text is presented in the following four units: (1) fundamentals of heating and cooling; (2) heating systems; (3) cooling systems; and (4) duct work. The information in each unit is presented in lecture format accompanied by laboratory exercises and questions/examples for class discussion. A bibliography and several charts illustrating the text material are found at the end of the module. (BM)