ABSTRACT
This chapter aims to define certain air properties fundamental to heating, ventilating, and air-conditioning (HVAC) design, and presents methods of determining these properties, and illustrate accepted methods of analyzing air-conditioning processes in HVAC systems. Standard atmospheric data are used by air-conditioning engineers to estimate the properties of air at various altitudes. Psychrometrics is the quantitative study of the thermodynamic properties of moist air and the use of these properties in analyzing air-conditioning processes. The psychrometric chart is designed to allow graphical analysis of air systems, eliminating the need to perform tedious calculations to compute the conditions of air at any point within the system. If the supply air gains too much energy as it circulates through the space, the space is overcooled, and if it gains too little energy, the space becomes progressively warmer and more humid.
