About Car Air Conditionersby Jessica Reed
It's hard to imagine a car without air conditioning, but car air conditioners have only been common for the last twenty years. Today, 80 percent of people in the United States drive a car with air conditioning. This is a relatively simple system in your car that provides relief from the heat and humidity outside. Much like a home air conditioning system, car air conditioners are for your comfort, and make car trips more enjoyable.
Car air conditioning comes standard in most of today's vehicles. Older vehicles were made without air conditioning. They were uncomfortable because when it was hot outside the car, it was hot inside the car as well. The only means of cooling the car was to roll down the windows. The first car air conditioning system was offered as an extra feature that could be added to your vehicle. This was first used by The Packard Motor Car Company. However, these air conditioning units were very large and didn't cool the car efficiently. They were also expensive. Fifteen years later, General Motors began to sell air conditioners that cooled the car significantly more than the Packard version.
The Packard Motor Car Company's first car with air conditioning was introduced in the year 1939. It was advertised as the world's only air conditioned car. These cars used a refrigeration system of air conditioners that were installed by Cadillac in 1941. However, the driver had to get out and shut off the air conditioning manually from where it was located--inside the trunk. After World War II, Cadillac started putting controls on the inside of their cars. In 1958, the Pontiac V8 came out with its more effective air conditioning system, which was easier to use and cooled the car better. Air conditioning became common in cars around the 1970's.
The purpose of the car's air conditioning system is simple. It's there to keep the car cool during a trip in hot or humid weather. The air conditioner makes the car more comfortable for the driver and passengers alike. Many of today's cars allow the temperature to be set to a certain degree and the air conditioner or heater will adjust the air until the desired temperature is reached. The only drawback to air conditioning is its affect on the gas mileage of the car. Studies are being done to determine how air conditioning affects a car's gas mileage as compared to how other things, such as rolling down the windows, affect the gas mileage.
The Packard and Cadillac cars featured the refrigeration system of air conditioning. As these were not very effective in cooling the car, the Pontiac V8's were invented and used a two-cylinder reciprocating compressor. They also used an all-brazed compressor as well as the magnetic clutch that was better for the car and its fuel consumption. As modern technology takes over, computers and sensors are added to help the air conditioner know exactly what temperature to keep the car at, and when to turn the air conditioner off. They also allow the passenger to have a separate set of controllers to adjust the air conditioner's temperature on their side of the car.
R-134a refrigerant, a gas, is inside the air conditioner's system. The compressor in your car adds pressure to it. The more pressure that is added, the hotter the gas gets. It absorbs the heat from all around it, thus causing it to heat up dramatically. Once it's hot, it goes through a series of tubes that allow the heat to be removed from the gas. Once the gas becomes cool enough, it turns into a liquid which creates the cool air we feel in our cars. R-134a is being banned in some states because it has been shown to be harmful to the atmosphere.
- photo_camera http://www.familycar.com/Classroom/ac1.htm, 17 Dec. 2008.