The central air conditioning system is saddled with the responsibility of disseminating cool air via its ducts. These supply ducts transport the cooled air through vents, to the office, home or factory. When the cool air comes from the air conditioner and circulates in the room, it gets warm over time and returns to the duct for a fresh set of cool air. Air conditioning units moisturize the air in the room, by circulating air with their circulating fans.


The wealthiest people in ancient times sought ways to curb the problem of the hot weather in America at the time. They used hand fans, but they were not effective, considering the prevalent heat. By the dawn of the 20th century, homes started having electric fans as things started changing.

The need to cool air industrially prompted the need for central air conditioning units to be made available on a commercial scale. By 1902, Willis Haviland Carrier manufactured the first central air conditioning unit. Today, he is revered and widely accepted as the founding father of air conditioners.

When Willis Haviland Carrier was manufacturing air conditioners, he did not have in mind that this invention for going to be needed in homes or for personal use. It was done solely for industries and manufacturing plants, in other to better their process of manufacturing. The printing industry, for example, had an issue of managing the heat emanating from the press, which causes the air of the plant to be moist. Therefore there was a dire need to solve the issue, as the heat affected the ink positioning on the paper. All of these were tackled by Willis Carrier’s first air conditioning unit.

The presence of chlorofluorocarbon also known as Chlorofluorocarbon and hydrochlorofluorocarbon as refrigerants have proved to be depletive to the ozone layer and unfriendly to the ecosystem. As a relief, Thomas Midgley Jr., discovered Freon which is way safer than the CFC and the HCFC AND IT IS BETTER FOR THE ENVIRONMENT. Other refrigerants subsequently introduced include R-410a, R-22, R-11, etc. This improved the acceptability rates of central air conditioning units by people in their homes, offices, and factories.


Willis Carrier’s company which continued the production of the air conditioners. With their dominance in the air conditioning market, they were able to sell it into people‚Äôs offices and working places, until its gradual demand for cooler air at homes. The first air conditioning unit was released in 1925. This release was done in New York City. It made use of coils to pump air with its central compressor. This process produces the cool air that is sent across the vents.

Engineer Schultz and Engineer Sherman produced the first air conditioning units fitting into windows ledges. These air conditioners were so efficient that they could cool up to three rooms at a time. However, upon their introduction to the markets, they were sold for between ten to fifty thousand dollars, making them seemingly expensive for the average Americans who needed to condition the air in their homes. This created a need for the reduction of prices, as the demand for air conditioners grew. By the 1950s, the usage of air conditioners in homes grew, with the moderation of prices of the units.

With the evolution of the air conditioning system, central air conditioning units surfaced in the markets by the 1970s. Senior citizens migrated to the hot southwest for the first time because air conditioning in places like Las Vegas Nevada made it livable for retirees. The central air conditioner still ran as the window box air conditioners, producing cool air with coils, condensers, compressors, and fans. The chilled air is generated in one section and sent throughout the house via wall and ceiling openings, windows and floor vents. The predominant refrigerant used by the central air conditioners was the Freon. However, over the years, after many ac repairs, it was discovered that the Freon was hazardous and destructive to the environment, so its use has been replaced by other less harmful refrigerants like R-422.