Data source: Beijing Changhong Air Conditioning Repair Center http://blog.tianya.cn/blogger/blog_main.asp?BlogID=3766321. There are many methods for refrigeration, and the following methods are commonly used for cooling: ① Liquid vaporization refrigeration, which uses the heat absorption effect of liquid vaporization to achieve refrigeration. Steam compression, steam absorption, steam jet, and steam adsorption refrigeration all belong to the method of liquid vaporization refrigeration. Currently, liquid vaporization refrigeration has the widest application, Beijing Changhong Air Conditioning after-sales service telephone. ② Gas expansion refrigeration, which uses the heat absorption of high-pressure gas expansion to reduce the temperature in a certain space and achieve refrigeration. It is only suitable for air conditioning systems and low-temperature water systems above 0℃. ③ Sublimation refrigeration, which uses the sublimation of solid carbon dioxide into gas, absorbing a large amount of sublimation latent heat from the surrounding environment to achieve refrigeration. ④ Melting refrigeration, which uses the phase change process of substances from solid to liquid, absorbing a large amount of melting latent heat from the surrounding environment to achieve refrigeration. ⑤ Chemical refrigeration, which uses endothermic chemical reactions to cool surrounding objects. ⑥ Thermoelectric refrigeration, which uses the thermoelectric effect of metals, i.e., when current flows through a thermocouple composed of two different metals, heat release and absorption effects occur at different junctions, and its heat absorption effect can be used for refrigeration. Currently, the main artificial refrigeration methods used include steam compression, steam absorption, steam jet, and thermoelectric refrigeration. Must-read for Changhong Air Conditioning repair; what are the methods to achieve artificial refrigeration?