An air conditioning appliance used to directly provide treated air to enclosed rooms, spaces, or areas. Usually referred to as an air conditioner. The cooling capacity of an air conditioner used for refrigeration is expressed in watts (watts), which is the amount of heat removed from a closed room, space, or area per unit of time. The regulations on the refrigeration capacity range of household air conditioners are not unified in various countries, with China setting it below 9000W. There are multiple classification methods for air conditioners. It can be divided into two types according to its structural form: integral type and split type. The overall style includes window style and wall style; The split type is divided into two parts: indoor unit and outdoor unit. The indoor unit can be ceiling mounted, wall mounted, floor mounted, embedded, desktop, etc. Classified by function into cold air type, heat pump type, cold air dehumidification type, cold air heat pump dehumidification type, heat pump assisted electric heating type, etc; According to the cooling method, it is divided into water-cooled and air-cooled. Household air conditioners are generally air cooled. An air conditioner generally consists of four parts: a refrigeration system, an air circulation system, an electrical control system, and a box (Figure 1) Refrigeration system: It mainly consists of a closed compressor, a capillary tube for throttling, an evaporator for heat exchange, a condenser, and connecting pipes to form a closed system. Fill the system with refrigerant (usually Freon R22). ② Air circulation system: mainly includes fan motors, centrifugal fans, axial fans, air ducts, dampers, air filtration devices, etc Electrical control system: mainly including temperature controller, selector switch, overload protector, heating electric tube protection device, electromagnetic directional valve, electrical circuit, etc. ④ Box part: mainly includes shell, chassis, panel, junction box, etc