1.Centralised/ Industrial Air Conditioning
We do not use small air conditioners like- window air conditioner in large buildings and industries due to high energy consumption. Central AC installation and its circuit is very hard. Therefore we use centralised air conditioners in the commercial and large buildind to cool down the temperature. This is an effective cooling system. It consumes less power than others. Ducts supply the chilled air to various locations. It is very expensive cooling system.It has various types of safety devices and control devices.
2.Types of Centralised Air Conditioners-Central AC Installation
Centralised AC are of two types 1. Direct Expansion System or DX System 2. Indirect or Chiller System. In DX System air flow takes place directly on evaporator. In this system installation of multiple plants are very easy. Leakage of referigerant does not effects others uints. Height difference between cooling coil and condenser unit is very low. A big compressor and condenser is a separate unit. Expansion Valve Evaporator and AHU is a separate uint. A big Blower is attached to AHU.
Working Method of Direct Expansion System- First of all connect DX System to supply. Compressor tranfers refrigerant to condenser. Condenser tranfers it to the evaporator. Evaporator absorbs heat of air. Before flowing over evaporator this air passes through the filters. Filters remove dust particles from air. Now this filtered and chilled air is transmitted through the ducts to the places where we needs cooling. The hot air goes back with help of air diffuser to the AHU Room. In AHU Room this hot air mixes with fresh air and sent to the evaporator continously. cooling tower cools down the teperature of hot refrigerant. Thermostat helps us to maintain temperature.
3.Indirect Cooling System or Chiller System
In this system we install air conditioning plant at a distnce from the place where we need cooling. Secondary Refrigerant is used in cooling condenser unit. This system has cell and tube type evaporators. Evaporator is in AHU in which a big blower is fitted also. This big blower absorbs the air of all sections and transmitts to the secondary refrigerant. Refrigerant absorbs the heat of this hot air. Thus blower transmitts the air of sections to the evaporator cell. Which reduces the temperature of internal air continuously. Mian Parts of Indirect Cooling System are- 1. Air Handing Unit 2. Air Washer Unit 3.Fan Coil Unit 4. Expanson tank
4. Advantages of Indirect Cooling System or Chiller System
- There is no unwanted noise. 2. Any desired teperature range can be achieved. 3. Cooling of one room does not affect the cooling of another room.