A vehicle without air conditioning is a concept that is hard to imagine for today’s people. In the promotional brochures of most vehicles, it is not even necessary to mention that there is air conditioning. Although it was described as a luxury in the past, air conditioning is now offered as standard equipment in every vehicle. However, we quickly forgot that this was not the case until recently, that we only travel in vehicles with heating. In the summer heat, we would open the windows and try to cool off, and especially long trips could turn into a nightmare. In this article, we will discuss the use and development of the first air conditioner in vehicles, slightly different from the issues we have examined so far.
At the end of the 19th century, when the first examples that could be described as cars began to be produced, it was never thought that a ventilation or air conditioning equipment would be needed. Because these first vehicles did not have many elements such as ceilings, doors and windows that today’s counterparts have. In those years, passengers were content to use their umbrellas to protect themselves from the sun. This process did not last long and with the development of the first covered vehicles in the early 20th century, a more comfortable journey became possible. However, this time, the ventilation and air conditioning of closed cabins emerged as a new problem.
In 1921, for the first time in the USA, a small electric fan was used to ventilate the interior of a vehicle. In 1930, the interior of a vehicle was cooled for the first time with the evaporative cooling method in the USA. In this method, the cold air obtained by the evaporation of water was blown inward from the open window of the cabin. Although very effective results could not be achieved, it went down in history as the first application in the world to cool the interior of a vehicle. Nine years later, a cooler was added to a Cadillac car for the first time, providing real cooling inside the cabin. The 0.37 kW cooling unit was mounted on a pedestal attached to the rear of the vehicle from the outside. With this device, cooling was done by blowing cold air from both sides of the front of the vehicle. In the same year, the American car manufacturer Packard launched its first air-conditioned car, working with R12 gas, which can heat in winter and cool in summer for the first time. The compressor and condenser of the unit were located under the hood and the evaporator in the trunk, and manual intervention was required on the belt driving the compressor to start or stop it. During the 1940s, different brands started to offer air conditioners in their vehicles as an option.
However, due to reasons such as the inability to provide fresh air to the cabin and the difficulty of controlling the unit, it did not become widespread. II. After World War II, air conditioning control was first brought into the cabin to the rear seats. However, this did not provide any significant convenience for the driver. In cases where the driver was alone, it was not possible to intervene in the air conditioner without going to the back seat. By 1953, there was a revolutionary development in this field. Harrison Radiator developed a much more effective system by positioning the evaporator under the hood instead of the trunk, and received a patent for this system. In this way, the problem of condensation and dripping on the rear seats was also prevented. In later years, this method became the standard for all vehicle manufacturers. In 1956, a hot gas bypass valve was added to the system to protect the evaporator from freezing. In 1964, the climate control was now located in the front, within reach of the driver. With this development, the driver could set the desired temperature value and control the air conditioner.
In the 1970s, as the ozone layer was depleted and R12 gas was found to be harmful, the use of different refrigerants in vehicle air conditioners, as in all other air conditioning devices, was investigated. With the Montreal protocol signed in 1987, the use of R12 gas was banned and R134a came to the fore as an alternative to this gas. The 1990s passed as a change process from R12 to R134a in vehicle air conditioners. USA. While this process was completed between 1991 and 1994 in Europe and Japan, it continued until the early 2000s in other countries. Today, with the F-Gas regulations, R-1234yf gas is being used instead of R134a in vehicle air conditioners.
Europe switched to the use of air conditioners later than the United States. While more than half of the vehicles produced in the USA at the beginning of 1970 were air-conditioned and the use of air-conditioning in vehicles became standard since the 1980s, it took the 2000s for Europe to reach this stage. A situation similar to Europe has been experienced in our country and vehicle air conditioning has become standard especially after 2010.
Vehicle air conditioners, ranging from a primitive cooling unit added to the outside of the vehicle later on, to a technology that can condition 3 different parts of the vehicle separately, automatically keep the determined temperature value constant and equipped with filters throughout an adventure of nearly 100 years, will continue to offer new features that will increase passenger comfort in the coming period.
Source: Süleyman KAVAS, Mechanic