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Air Conditioning Systems
Air conditioning has rapidly grown over the past 50 years, from a luxury to a standard system included in most residential mercial buildings. In 1970, 36% of residences in the . were either fully air conditioned or utilized a room air conditioner for cooling (Blue, et al., 1979). By 1997, this number had more than doubled to 77%, and that year also marked the first time that over half (%) of residences in the . had central air conditioners (Census Bureau, 1999). An estimated 83% of all new
homes constructed in 1998 had central air conditioners (Census Bureau, 1999). Air conditioning has also grown rapidly mercial buildings. From 1970 to 1995, the percentage mercial buildings with air conditioning increased from 54 to 73% (Jackson and Johnson, 1978, and DOE, 1998).
Air conditioning in buildings is usually plished with the use of mechanical or heat-activated equipment. In most applications, the air conditioner must provide both cooling and dehumidification to fort in the building. Air conditioning systems are also used in other applications, such as automobiles, trucks, aircraft, ships, and industrial facilities. However, the description of equipment in this chapter is limited to monly used mercial and residential buildings.
Commercial buildings range from large high-rise office buildings to the corner convenience store. Because of the range in size and types of buildings in mercial sector, there is a wide variety of equipment applied in these buildings. For larger buildings, the air conditioning equipment is part of a total system design that includes items such as a piping system, air distribution system, and cooling tower. Proper design of these systems requires a qualified engineer. The residential building sector is dominated
by single family homes and low-rise apartments/condominiums. The cooling equipment applied in these es in standard “packages” that are often both sized and installed by the air conditioning cont