Verify the vehicle uses the correct refrigerant type specified on the under-hood label
Inspect the AC system for leaks or damage before adding refrigerant
Wear safety glasses and gloves
Turn the engine off before connecting any equipment
Locate the low-pressure service port
Attach the refrigerant hose or gauge to the low-pressure port only
Start the engine
Turn the AC to maximum cold, maximum fan, and recirculation mode
Open the refrigerant can valve slowly
Add refrigerant in short bursts while monitoring the gauge
Keep the can upright unless the product instructions say otherwise
Stop adding refrigerant when the pressure reaches the recommended range
Disconnect the hose carefully
Replace the service port cap
Check AC performance after charging
Do not overfill the system
Do not mix refrigerant types
Do not add refrigerant if the system is empty without first repairing leaks and evacuating the system
Use a certified technician if you are unsure or the system requires major service