Frequently Asked Questions

Can I Recharge the Freon in My Auto A/C?

It’s possible to recharge an auto ac system with freon as a do-it-yourself project if you can obtain the correct refrigerant for your vehicle, take the required precautions and follow the appropriate steps.

Obtaining refrigerant may be difficult because the sale of automotive refrigerants R12 and R134 to “noncertified” people has been prohibited since 1992. Certification requires that technicians pass an EPA approved written exam.

A major safety precaution is the proper identification of the low and high side service fittings. If a can of refrigerant is attached to the high side fitting, the back pressure may cause the can to explode. If you aren’t clear as to which fitting is the high side, you shouldn’t attempt to recharge a system yourself. Wear eye protection and avoid direct contact between your skin and the refrigerant.

If you have the correct refrigerant and equipment, the basic steps for recharging an a/c system are:

1. Properly identify the low side fitting.

2. Following the manufacturer’s directions, attach a refrigerant can to a gauge set. Open the valve momentarily to bleed out any trapped air. Then connect the gauge set to the low side service fitting with the can in an upright position.

3. Start the car and place the a/c on high. The compressor should engage and suck the refrigerant from the can and into the vehicle’s a/c system. Additional cans may be necessary. The most common do-it-yourself mistake is overcharging. An overcharged system, like an undercharged one, has a reduced cooling efficiency.

4. When the system is fully charged, disconnect the gauge set.

To work properly, the system needs the right amount of the correct refrigerant. With the difficulty in obtaining refrigerant and the hazards involved, it is best to leave the recharging of an auto ac system to the professionals.