AIR CONDITIONING SUMMARY
AIR CONDITIONING SUMMARY
Comfort and industrial processes use air conditioning. It increases the comfort to living beings and improve the quality of industrial products.
Definition Of Air Conditioning
It controls simultaneously four parameters, temperature, humidity, purity and velocity of air in a closed space. Further, air conditioning is cooling in summer, heating in winter with ventilation.
- Comfort, food preservation, measuring instruments for better accuracy and manufacturing processes require air conditioning.
- Comfort Air Conditioning is of three types, namely, summer air conditioning, winter air conditioning and year round air conditioning.
- Human comfort is required in homes, offices and restaurants.
- All types of vehicles, namely, cars, buses, trucks, trains and airplanes use air conditioning..
- Printing, drugs, rubber and textile industries for controlling conditions to result in more production with better quality need air conditioning.
- Shops, cinemas, hospitals, libraries, computer centers, beauty saloons, malls, telephone exchanges, data processing centers, mines and museums need air conditioning..
Human Comfort Conditions
- Human comfort conditions are temperatures between 22 to 270C with relative humidity between 35 to 60 %, CO2 ≤ 600 ppm, CO≤ 25 ppm, odorless, virus free, fungus free and air velocity from 0.20 to 1.2 m/s.
Types Of Air Conditioning Units
- Air conditioning units are central, unitary and window units.
Window units are used up to 3 ton capacity. Unitary units are from 10 to 50 tons capacity and central air conditioning plants are for a cooling capacity of more than 50 tons. The main refrigerant used is R-22 in window air conditioners and central air conditioning plants. In the unitary units, refrigerant used is R-410 As. Room conditions change to comfortable conditions using various processes of simple cooling, simple heating, heating and humidification, cooling and de-humidification .
Central air conditioning plant
Main components of central air conditioning plants are compressor, condenser, expansion valve, evaporator, fans and blowers, filters louvers and ducts. Air conditioning requires fresh ventilation to maintain requisite level of oxygen in the space being air conditioned. Air conditioning deals with temperatures above 0 C. Central air conditioning plants use Fan coil units and Air Handling Units. Further, central air conditioning plants are of two types, namely, direct expansion type and chilled water systems. Main supply, main return and branch ducts are used in the central air conditioning system.
Heating Ventilation Air Conditioning (HVAC)
Complete system of heating, ventilation and air conditioning is called HVAC.