How do I add refrigerant to my AC system?

To add refrigerant to your AC system, you will need to locate the service valves on the system, typically found near the compressor unit. Attach a refrigerant gauge and hose to the low-pressure service valve. Start the AC system and slowly add refrigerant until the pressure reaches the recommended level. Be sure to follow safety precautions and consult a professional if you are unsure.