Air Conditioning System PAU MAU AHU RCU DDC FCU FFU

Air Conditioning System PAU MAU AHU RCU DDC FCU FFU It is a centralized air treatment system, which originates from the forced hot air heating and ventilation system in which equipment is centrally located and heated air is distributed through air ducts. The basic centralized system is an all-air single-zone system that generally includes fans, heaters, coolers, and filters. The AHU mentioned here refers to the primary return air system. Its basic working process is: after the fresh air from the outside is mixed with part of the indoor return air, the dust, smoke, black smoke and organic particles in the air are filtered out through the filter. Harmful Substance.

 

----------------------------AHU----------------------------
Combined air conditioning box: It mainly extracts indoor air (return air) and some fresh air to control the outlet air temperature and air volume to maintain the indoor temperature.

----------------------------PAU----------------------------

Pre-cooling air conditioning box: Primary Air Unit pre-processes outdoor fresh air and sends it to the fan coil unit (FCU).

----------------------------RCU----------------------------

 

(Recycled air handling unit) circulating air conditioning box.

 

----------------------------MAU----------------------------

Brand new fan unit: It is an air conditioning device that provides fresh air. Functionally, it can achieve constant temperature and humidity or simply provide fresh air according to the requirements of the use environment. The working principle is to extract fresh air from the outdoors, undergo dust removal, dehumidification (or humidification), cooling (or heating), etc., and then send it indoors through a fan, replacing the original air in the room when it enters the indoor space. Of course, the functions mentioned above must be determined according to the needs of the use environment. The more complete the functions, the higher the cost.

----------------------------DCC----------------------------

Dry cooling coil (referred to as dry coil or dry cooling coil): is used to eliminate sensible heat in the room.

----------------------------Direct Digital Control----------------------------

----------------------------FCU----------------------------

Fan coil unit: Fan Control Unit Fan coil unit is the terminal device of the air conditioning system. Its working principle is to continuously recirculate the air in the room where it is located, so that the air is cooled (heated) after passing through the cold water (hot water) coil to Keep the room temperature constant. Mainly relying on the forced effect of the fan, the air is heated when it passes through the surface of the heater, thereby strengthening the convection heat exchanger between the radiator and the air, which can quickly heat the air in the room.

----------------------------VAV----------------------------

Variable air volume air conditioning system (VAV) control principle: The variable air volume controller and the room thermostat together form indoor cascade control, using indoor temperature as the main control variable and air flow as the auxiliary control variable. The variable air volume controller compares the difference between the actual temperature detected by the room temperature sensor and the set temperature to output an adjustment signal for the required air volume, adjusts the air valve at the end of the variable air volume, and changes the air supply volume to keep the indoor temperature at Predetermined area. At the same time, the air duct pressure sensor detects pressure changes in the air duct, uses PI or PID adjustment, and controls the speed of the variable air volume air conditioner blower through the frequency converter to eliminate the influence of pressure fluctuations and maintain the air supply volume.

----------------------------FFU----------------------------

Fan Filter Units, the Chinese meaning is fan filter unit (unit)'. That is, the fan and filter (high-efficiency filter (HEPA) or ultra-high-efficiency filter (ULPA)) are combined together to form a terminal purification device that provides its own power. To be precise, it is a modular terminal air supply device with its own power and filtering function. The fan sucks air from the top of the FFU and filters it through HEPA. The filtered clean air is evenly sent out on the entire air outlet surface at a wind speed of 0.45m/s±20%.

 

Keywords: PAU   MAU   AHU   RCU   DDC   FCU   FFU