In the early 1900s, there’s very little that a person could do during the hot summer months to lower temperatures except to escape to the seashore or to the mountains. However, this has changed today; thanks to the modern air conditioning system. With the modern AC unit, you can stay cool and comfortable anywhere regardless of outdoor temperatures. Most stores, movie theaters, hotels, restaurants, and offices have air conditioning systems.
Air Conditioning Defined
While the main function of air conditioning systems is to make you feel cool, these systems can do much more than this. For instance, they control humidity or the moisture content of air circulating in a room. Secondly, air conditioners filter air to ensure that air circulating in a building is free of impurities. During cold winters, air conditioning systems can add moisture to air circulating in a room to ensure the humidity levels are optimum. As you can see, air conditioning helps to create an artificial environment inside an enclosed space. This can be a house, office or business premises.
Air conditioning in dry climates can be as simple as using a fan to pass dry air through a soaked fiber mat. As the air passes through the mat, water evaporates, absorbing heat from the air as a result. Please note that the added moisture will not cause any discomfort. Also note that this type of air conditioning is not possible in hot humid environments since air already contains excess moisture. In addition to improving comfort in homes, offices, schools, restaurants and business premises, air conditioning also has many other uses. Many industries use air conditioners to keep air circulating in their plants cool, clean and at the right humidity level. In the textile industry, for instance, air conditioning is used to prevent cotton and wool, among other types of textile fibers, from shrinking or stretching due to temperature and humidity variations.
Excessive humidity can cause metallic parts to corrode, and this can lead to serious problems especially when precision instruments or rocket components are involved. In the health care industry, the wrong temperature can lead to spoiling of a batch of vaccines or antibiotic culture. That is why air conditioning systems are widely used in the industry. In the deep gold and diamond mines of South Africa, air conditioning is used to enable mine workers to operate in an inhospitable environment without suffocating. In the US space program, air conditioning is used in every aspect.
For centuries, researchers and innovators have brainstormed and experimented with various air conditioning methods. For instance, the ancient Romans and Egyptians used to hang wet woven mats across the entrances of their homes, so hot air was cooled as it circulated within and around the house. In the 15th century AD, a famous inventor and artist invented the water-powered fan. As man became more interested in science, more air conditioning systems were developed. Hundreds of ideas were developed, but none worked. In fact, some techniques made things worse by increasing humidity. Air is known to absorb moisture, thereby increasing humidity levels.
Highly humid air feels sticky and is uncomfortable to breath. It is was not until 1902 when Willis H. Carrier developed the first machine that cooled air and kept humidity low at the same time. That is why Mr. Carrier is considered the father of modern air conditioning. He built the machine for a Brooklyn, New York, printing plant that had issues printing in color due to humidity variations. Normal paper usually shrinks when air is dry and stretches in humid air. At the time, each color had to be printed separately, so printing multiple colors on the same sheet of paper was challenging as the colors did not line up properly due to the changes occasioned by variation of humidity levels. Carrier saved the situation by inventing a machine that maintained a constant humidity level at all times. In addition to improving the quality of color printing, Carrier’s air conditioner also made the working environment more conducive for workers at the printing plant. The invention marked the advent of modern air conditioning.
After the first Carrier machine was developed, more plants adopted the invention. In the period leading to WWI and the war period, air conditioning was being used in ammunition factories. However, the average consumer was not aware of the invention until 1920, when hundreds of restaurants, departmental stores, and movie theaters installed air conditioners. People used to get into these places just to escape the hot and sticky air outside. In the 1930’s, air conditioning systems became more and more popular, leading to the development of the central air conditioning system.
This new system had the capability of cooling whole office buildings as well as apartment buildings from a central location. In the same way, buildings could be heated from one central location. In the same period, smaller air conditioners that could cool a single room were invented. After World War II, these small units could be found in private homes. Later on, a system that combined both heating and cooling in one unit could be found in both private and public buildings.
How Air Conditioning Systems Work
Air conditioning machines simply extract heat from the air, leaving it cooler than it was. The working principle is similar to that of a refrigerator, but air conditioners are not designed to produce extremely low temperatures. The air conditioner has a metallic tube that coils its way from one end of the compressor pump to the other. A compressed refrigerant is released from the compressor pump and expands as it moves through the refrigerant tubing. As it expands, it extracts heat from air passing through the air handling unit. This reduces the temperature of air. After extracting heat, the refrigerant is condensed into a liquid, dumping heat through the condenser coils in the process. The cycle continues until the desired room temperature is attained.
An air conditioning unit has a thermostat, which helps to maintain a constant temperature by turning the air conditioner on and off as required.