What happens if too much refrigerant is added to a car's air conditioning system?

[LaLondyn]

Adding too much refrigerant to a car's air conditioning system will increase the pressure in the system. When the air conditioning control system detects excessive pressure, it will frequently cut off the compressor's operation, resulting in poor cooling performance. Additionally, the consistently high pressure in the AC lines may cause damage to the system's components. The principle of air conditioning involves compressing gas into liquid and then converting the liquid back into gas. The process of liquid converting to gas absorbs heat energy, thereby releasing cool air. If there is too much refrigerant, it occupies the space needed for the gas conversion, preventing the liquid from fully transforming into gas, which leads to reduced cooling efficiency. Typically, there is a receiver-drier in the system where you can observe the refrigerant level—excessive bubbles indicate insufficient refrigerant. However, most people don't check this; instead, they can usually tell if refrigerant is low by feeling the airflow at the vents. Refrigerant is usually only added when the cooling performance noticeably declines.