... condenser water system, and condenser water pumps. The purpose of the water system is (1) to transportchilled water and hot water from the central plant to the air-handling units, fan-coil units, and ... riser, and the supply duct; and to the conditioned space through the fan-powered box and slot diffusers. Water SystemThe water system includes chilled and hot water systems, chilled and hot water ... beginning of a new millennium, in addition to the publication of ASHRAE Standard90.1-1999 and ASHRAE Standard 62-1999, often called the Energy standard and Indoor Air Qual-ity standard, the...