According to the Clear Air Act, it does seem to be illegal: "Under the Clean Air Act, releasing non-ozone-depleting refrigerants such as HFC-134a into the atmosphere has been prohibited since November 15, 1995. Section 609 of the Act requires EPA to promulgate standards for refrigerant recycling equipment and for the proper use of that equipment. Four problems account for the majority of the problems with the Nissan Altima’s AC system. These problems are: The compressor control valve. Refrigerant leak. Electrical climate control failure. AC Compressor. The good news is, Nissan Altima AC problems are usually repairable. 3. The A/C clutch is not engaging. The A/C clutch on your compressor engages whenever you turn on your air conditioner, and it usually sounds like a small click. The clutch relies on the pressure of the system to engage on most vehicles. If the refrigerant is too low or too high, the vehicle may not allow the compressor clutch to engage. Ensure that the charging hose is securely attached to the canister. Attach the Charging Hose: Attach the charging hose to the service valve on the liquid line of the air conditioner. Ensure a tight and secure connection to prevent any refrigerant leakage during the process. The most common causes that hinders normal operation of air conditioning system on your Subaru Forester are dirty cabin air filter, refrigerant leak, dirty or clogged condenser, dirty or clogged evaporator, bad blower motor, defective compressor, faulty blend door actuator or any fault in the electrical system. 1. Dirty cabin air filter. Qq85pQ.