According to the power source, automobile air conditioners can be divided into independent air conditioners and non-independent air conditioners.
1.1 Independent air-conditioning: There is a special power source (such as a second engine) to drive the operation of the entire air-conditioning system. Generally used in long-distance freight, high-floor large and medium buses and other vehicles. Independent air conditioners require two engines, high fuel consumption and high cost, and their repair and maintenance are very difficult.
1.2 Non-independent air conditioning: an air conditioning system that directly uses the driving power (engine) of the car to operate. The non-independent air conditioner is operated by the compressor driven by the main engine and controlled by an electromagnetic clutch. When the power is turned on, the clutch is disconnected and the compressor stops, thereby regulating the supply of cold air to achieve the purpose of controlling the temperature in the cabin. The advantages are simple structure, easy installation and arrangement, and low noise. Because it needs to consume 10%-15% of the power of the main engine, it directly affects the acceleration performance and climbing ability of the car. At the same time, its cooling capacity is affected by the speed of the car. If the car stops running, its air conditioning system also stops running. Nevertheless, dependent air conditioners have gradually become the leading products in the market due to their lower cost (relative to independent air conditioners) and reliable quality. Currently, most cars and trucks use this type of air conditioner.