air conditioner is an electric appliance or system. It is designed to control the temperature
and humidity of indoor air. Air conditioners circulate cool air and decrease the humidity of the air in a building or a room. Air conditioners therefore keep the indoor air cool and dry.
Types of air condítioners
Room air conditioners and central air conditioners are two basic types of air conditioners. A room air conditioner is generally used to cool a single room. It can be fixed on a window. Central air conditioners are used to cool the entire house or office. There are two types of central air conditioners: split system air conditioners and single-package air.
Air conditioners are used in buildings houses, offices, and cars. They condition and
cool the air with the help of a refrigeration cycle. The compressor is the most important element of an air conditioner. It heats freon gas by compressing it. The hot gas is passed
through a set of coils to make it cool. The cold gas is again passed through a set of
coils. It absorbs the heat of the place and makes it cool.
conditioners. In a split system air conditioner, one of the heat exchangers, the compressor, is located outdoors while the other, the coil, is located indoors. A single-package air conditioner has both heat exchangers located in the same unit.
Early cooling techniques
The history of cooling of air in houses and buildings dates back to the time of ancient Egyptians Persians. The ancient Egyptians developed a method to circulate aqueduct water through the walls of thier houses. This method cooled the houses aqueduct water usage was expensive for poor people. In medieval Persia, people used cisterns and wind tower
cool their houses in the summer season. Cisterns were large open pools constructed in central courtyards in which the rainwater wascollected. The water of the cistern evaporated to cool the air of the building. Wind towers were tall towers with windows that caught the wind to direct the airfow into the building.
Development in the 19th century
Michael Faraday was a British scientist and inventor. In 1820, he discovered that compression and liquefaction of ammonia could chill the air after the evaporation of liquefied ammonia. In 1842, a physician, Dr John Gorrie used compressor technology for his patients in his hospital in Florida. The compressor technology helped him in making
ice. He tried to use the ice-making machine for the regulation of temperature in buildings but could not due to a leakage in the machine. In spite of the
irregular performance of his prototype, he was granted a patent in 1851. However, Gorrie
did not get the money to develop the machine due to the death of his financer. There was no further development of air conditioners for the next 50 years.
Stuart W. Cramer developed ways to add moisture to the air in his textile mill in 1906. He used the moisture and ventilation to control the humidity in textile plants. This process of evaporation of water in air to provide a cooling effect is known as evaporative cooling. In the earliest air conditioners, poisonous and flammable gases such as ammonia, methyl chloride, and propane were used, resulting in accidents due to leakage. The
first chlorofluorocarbon gas, freon, was invented by Thomas Midgley in 1928. This gas was safe for humans but was later found to be the cause of the depletion of the ozone layer. Non-ozone depleting refrigerants, such as puron, were developed to avoid the use of ozone depleting gases.
Willis Haviland Carrier
Willis Haviland Carrier invented the first modern electrical air conditioning in 1902. He designed the machine to improve the manufacturing process control in a printing plant.
The machine could control the temperature as well as humidity. The low temperature and humidity helped to maintain the consistency of paper dimensions and the alignment of ink.
The air conditioning technology was used to increase the productivity in workplaces. Later, it was used in homes and cars. The Carrier Air Conditioning Company was formed to manufacture air conditioners.