A low refrigerant charge can cause major damage to your car's air conditioner. Unlike some compressors used in the '70s, which had their own oil supply, most current designs rely on a sufficient refrigerant charge to carry oil through the system. If that charge is lost -either partially or completely - the compressor may starve for oil and fail shortly thereafter. This results in a major expense, not only for the compressor, but for related items that will have to be replaced if the compressor fails.
There was a time you simply flipped on your air conditioner in the spring to see if the air coming from the outlets was cold. If the temperature seemed to be warm, you merely brought the car in and had some refrigerant added. At one point, it was even considered normal for an air conditioning system to lose a pound of refrigerant per year.
Since that time, attitudes about refrigerant loss have changed drastically. That's because scientists have concluded that R-12 refrigerant, a Chlorinated Fluorocarbon (CFG) also know as FREON, is partly responsible for depletion of the earth's ozone layer. To reduce the loss of refrigerant, car manufacturers now make their systems much more leak-resistant by using improved materials for lines, hoses and seals. Federal and state regulations also require that repair shops have the correct equipment and training for handling refrigerant