1. When you have dry eyes, tired eyes, chest tightness, poor breathing, and smell sour in the car, it means that the air pollution in the car has been quite serious. You must replace the car's air-conditioning filter as soon as possible.
2. The wind blown out by the air conditioner has a peculiar smell. The reason may be that the air-conditioning system has been used for too long, and the internal system and the car AC cabin filter are caused by moisture and mold. Faced with this situation, it is recommended to clean the air-conditioning system and replace the air-conditioning filter.
3. Even if the car air conditioner filter has just been replaced, even if the internal circulation is turned on, the peculiar smell of the external and internal air cannot be removed. The reason is that ordinary air-conditioning filters may be used. It is recommended to use activated carbon series air-conditioning filters.
4. If this happens: the air conditioner has been turned on to a large enough gear, but the air output for cooling or heating is very small. If the air-conditioning system is normal, it may be that the car air-conditioning filter used is poorly ventilated, or the air-conditioning filter has been used for a long time and should be replaced in time. And it is important to choose the realiable car air filter manufacturers.
In some developed countries, due to their strong environmental awareness and good air quality, when a car travels more than 20,000 kilometers, the car owner usually replaces the car's air-conditioning filter.