What Causes Frost on the High-Pressure Pipe of a Car's Air Conditioning System?

[McAthena]

The reasons for frost formation on the high-pressure pipe of a car's air conditioning system are as follows: 1. Blockage: The filter screen or the evaporator inside is too dirty, causing blockage and obstructing ventilation. 2. Indoor Unit: The fan speed of the indoor unit is too slow, leading to poor heat exchange. 3. Fault: There is a leak or damage in the air conditioning pipeline, resulting in a lack of refrigerant (Freon). Solutions are as follows: 1. Check whether the connecting pipe is tightly secured. If the connecting pipe was extended during installation, inspect the welding points for any pinholes. If the connecting pipe was shortened during installation, focus on checking whether the flared ends are properly made. 2. Capillary Tube Blockage: If the capillary tube inside the unit also shows frost, and the current continuously rises from startup until the compressor overheats and shuts down, releasing the refrigerant and replacing the capillary tube can resolve the issue.