In the statistics and analysis of air conditioning fault data, it is found that a considerable proportion is caused by repeated maintenance or not timely inspection. For example, the first time a customer complained that the air conditioner was not cool, the repair shop replaced the compressor. But after a period of time, the customer complained about the same problem again, and the reason was that the technicians did not comply with the relevant regulations for maintenance. Air conditioning as a separate circulation system, its maintenance and repair must be carried out in strict accordance with the provisions, mainly in the following five aspects.

1、打开制冷剂管路后，应立即使用合适的密封塞将所有连接孔密封，防止湿气和灰尘进入系统导致制冷输出降低和造成部件损坏，例如空调不制冷、管路堵塞、压缩机损坏等；另外，必须更换干燥罐。

1. After the refrigerant pipeline is opened, all connecting holes should be sealed immediately with suitable sealing plugs to prevent moisture and dust from entering the system, which will reduce the refrigeration output and cause damage to components, such as air conditioner not cooling, pipeline blockage, compressor damage, etc.; in addition, the drying tank must be replaced.

2、所有新部件应存放在干燥、封闭的区域内，只能在安装的前一刻拆下密封塞。干燥罐或干燥剂应在打开包装后20min之内安装，然后仔细排空系统，进一步排出已渗透的湿气。

2. All new parts should be stored in a dry, enclosed area and the sealing plug can only be removed immediately before installation. The drying tank or desiccant should be installed within 20 minutes after opening the package, and then the system should be drained carefully to further drain the permeated moisture.

3、当压缩机润滑油的颜色为黑色时，应立即检查空调管路；如果管路存在黑色粉末，说明压缩机已磨损，必须更换，且还要对管路进行彻底清洗。另外，在加注时必须根据WIS要求校正机油和冷媒的加注量，防止加注不足或过多而引起的部件损坏。

3. When the color of the compressor lubricating oil is black, check the air conditioning pipeline immediately; if there is black powder in the pipeline, it means that the compressor has been worn and must be replaced, and the pipeline should be cleaned thoroughly. In addition, the filling amount of engine oil and refrigerant must be corrected according to wis requirements to prevent component damage caused by insufficient or excessive filling.

4、在雨季，电路容易遇水腐蚀，其后果可能导致线路短路，使包括空调系统在内的电控系统出现故障，严重的可引起火灾，烧毁车辆。因此，在雨天行驶尤其是涉水后，即使车辆正常行驶，也必须到维修厂进行全 面检查，时刻注意电路防潮保养。下图所示为空调部件腐蚀情况。

4. In rainy season, the circuit is easy to be corroded by water, which may lead to short circuit of the circuit and make the electronic control system including the air conditioning system fail. In serious cases, it may cause fire and burn down the vehicle. Therefore, in rainy days, especially after wading, even if the vehicle runs normally, it is necessary to go to the repair shop for a comprehensive inspection, and always pay attention to the moisture-proof maintenance of the circuit. The following figure shows the corrosion of air conditioning components.

5、在空调抽真空时，为了保证将空调系统内的空气与水分彻底排空，抽真空的时间更 好不要少于20min，将系统抽真空至500Pa，并在抽真空后封闭所有的阀和关闭抽注机，进行保压10min后观察空调系统是否存在泄漏。

5. When vacuumizing the air conditioning system, in order to ensure that the air and moisture in the air conditioning system are completely evacuated, the vacuumizing time should not be less than 20 minutes. Vacuumize the system to 500 PA, close all valves and close the pumping and injection machine after vacuumizing, maintain the pressure for 10 minutes, and then observe whether there is leakage in the air conditioning system.