Hi everyone, In this blog, I am going to deal with the topic, "Air conditioners". The word itself gives a very cool feeling. Isn't it? INTRODUCTION: # Air conditioners may be defined as the devices or instruments used for conditioning the air i.e. the temperature and humidity of air is regulated. # The air conditioners may also be used for, * Filtering the air- by the use of various filters which are inserted at the entrance of air conditioner. * Distribution of air- with the help of fans. * Regulates the temperature and humidity of outside air. WORKING OF AIR CONDITIONERS: # The air conditioners generally follow 2 approaches, Approach 1- here, the humidity and temperature of air is increased until it reaches saturation i.e. humidification by passing the air through water sprays and then heated. Air is filtered initially. t1, h1 > t2, h2 Approach 2 - it is a dehumidification process where the humidity and temperature of air is decreased to the desired level i.e. till adiabatic cooling lines. Air is re-heated until desired temperature. TYPES OF AIR CONDITIONERS: 1. Self-contained air conditioners. 2. Central air conditioners. Self- contained air conditioners: * As you all might have known, these are the conditioners which we usually use and keep in our homes. * So, these are also called as room air conditioners or residential air conditioners. These follow both the above explained approaches. Construction: * the components present in a self- contained air conditioner are:- Filters Humidifiers Fan Heating coils Compressors Evaporators Condensers. Working: * Fan forces the air into the system and through the other components. * The air is filtered initially and then humidified in the humidifier. * Then it is heated by heating coils to evaporate the water vapor present in it and then it is condensed in the compressor due to which cooling effect is produced. Central air conditioners: * This type of air conditioners are generally seen in big hotels, shopping malls etc. * They are expensive. * These types of air conditioners working is based on 2nd approach only. Construction: Construction is similar to that of self-contained air conditioner but here additionally spray nozzles and pump are present. Working: * The fan present pulls the air from outside into the air conditioner. * Filters filter the air of suspended particles. * It is then heated by heating coils to high temperatures. * Then it is humidified. * In the water reservoir, a pump is present which pumps water into the tube, then sprayed through spray nozzles onto air. Therefore, humidity of air increases. * This humidified air then passes into a chamber where the water droplets get entrapped. * It is re-heated by heating coils to the desired temperature. * The fan then directs the air to the outlet, then through the pipelines to the required area. CONCLUSION: Hope all of you have understood the working of our air conditioners and would remember whenever you sit in its cool air. REFERENCES: Pharmaceutical engineering by C.V.S.Subrahmanyam, pg-473.