Retrofitting

Many businesses store chemicals such as chlorine, acids, solvents, and strong cleansers that must be mechanically ventilated all the time. Usually, the entire storeroom is exhausted by a rooftop or wall- mounted fan. This fan […]

A four-pipe fan coil unit (FCU) has much the same internal workings as a two-pipe system, but with both a heating and cooling coil. The thermostat controls both the chilled water and heating water valves. […]

Large air-handling units of a constant-volume system provide both heated and cooled air to a zone. Each unit has both heating and cooling coils that are alternatively active during the winter and summer. Variable air […]

Outside air quantities supplied by an air handler are based on peak occupancy, which happens infrequently in many locations. Furthermore, when the zone is occupied at its maximum rate of occupancy, it’s often satisfactory if […]

Many buildings exhaust more air than the outside air requirements of the occupants. This is especially true for facilities that exhaust from laboratories, kitchens, or laundries. Any air that’s exhausted beyond the minimum cubic feet […]