![]() Humidifiers are usually used in cold days where maintaining hot climate is desired however this will accompany low-humidity levels, and thus the use of humidifier becomes essential to maintain the comfort edge. It is a system which is responsible for increasing the humidity in the conditioned zone. In addition, preheater coil will prevent the freezing of water inside the coils in cold days. The task of preheating coil in hot days is to reduce the entering fresh air’s relative humidity, thus preventing possibly the condensation of water vapor on cooling coil, hence preventing frost formation on the cold coil. Preheating coil is placed at AHU entrance before cooling and heating coils. Coil placed in AHU where hot liquid or vapor water from boilers is circulating. ![]() Dampers are used to control the amount and direction of air before or after conditioning is performed. Mixing processes are performed to obtain the desired air temperature and humidity or to maintain energy-efficient performance.ĭampers. It is place where fresh air is mixed with zone return air or with fresh conditioned air. Filter type used may depend on application type. Filters or strainers are placed at the early air path in AHU. Coil placed in AHU where cold water from chiller is circulating in medium- and large-capacity AHU or expanded refrigerant in small-capacity AHU.įilters. Electric motor is used to provide the rotating motion to the supply fan.Ĭooling coil. Centrifugal fan type is used to provide the conditioned air to various zones.įan motor. The main components of the air handling unit shown in Figure 1 are described below: It is may be of interest to note that this chapter is suitable for undergraduate level students in the fields of HVAC and R, mechanical, and construction engineering.Ī schematic diagram of an air handling unit with its main components. In addition, all provided systems are further explored through several developed schematic diagrams enabling the identification of their various components and the understanding of their working principles. Specifically, all-air systems, all-water systems, and air-water systems are discussed. The present chapter reviews the central air conditioning systems and applications. Therefore, there is a continuous need for an updated material in the literature that reviews the central air conditioning systems and applications, which is the motivation of the present chapter. In fact, a pre-assessment of the construction type and budget available is required for selecting the proper type of central air conditioning system. Therefore, the selection of proper type of central air conditioning system is a crucial target in the construction industry as improper selection can maximize initial and/or running costs of the system and decreases the human comfort and indoor air quality levels. In very large buildings, like hotels and hospitals, the exterior condensing unit is often mounted somewhere on the roof.It became evident nowadays that modernization influences domestic and commercial HVAC industry, and thus high technological and energy-efficient central air conditioning systems are demanded. It's in a separate all-weather housing outdoors. Bigger air conditioners work a little differently: Central air conditioners share a control thermostat with a home's heating system, and the compressor and condenser, the hot side of the unit, isn't even in the house. The hot air vents from the back of the unit, while the condenser coils and a fan cool and re-circulate indoor air. Window air conditioners have all these components mounted into a relatively small metal box that installs into a window opening. There are some additional sensors, timers and valves, but the evaporator, compressor, condenser and expansion valve are the main components of an air conditioner.Īlthough this is a conventional setup for an air conditioner, there are a couple of variations you should know about. ![]() The compressor is actually a large electric pump that pressurizes the refrigerant gas as part of the process of turning it back into a liquid. Once in the evaporator, the refrigerant experiences a pressure drop, expands and changes back into a gas. It regulates the amount of compressed liquid refrigerant moving into the evaporator. In between the two sets of coils, there's an expansion valve. The hot side contains the compressor, condenser and another fan to vent hot air coming off the compressed refrigerant to the outdoors. The cold side of an air conditioner contains the evaporator and a fan that blows air over the chilled coils and into the room. Compressor - A pump that pressurizes refrigerant.Expansion valve - regulates refrigerant flow into the evaporator.Evaporator - Receives the liquid refrigerant. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |