ABSTRACT
Air conditioning, as well as other thermal environment control systems for buildings, relies on a number of major technologies and equipment for the generation of the required cooling and heating energy, as well as the distribution of this energy to the various air handling plant and conditioned spaces. This chapter describes the major cooling and heating technologies and equipment employed for this purpose, their important characteristics and selection criteria. The cooling and dehumidification in air conditioning systems is provided in most cases either by chilled water or direct expansion refrigerant coils. The compressor is the heart of the refrigeration system. Its function is to pump the refrigerant round the circuit and provide the required pressure differential between the low-pressure evaporator side of the system and the high-pressure condenser side of the system. The performance of refrigeration and heat pump systems is expressed as the ratio of useful heat transferred to work input and is usually called the coefficient of performance.
