How to Convert From R12 Freon to R134a
- 1). Dispose of the R12 in your system safely by taking your vehicle to a certified air conditioning repair shop. Make sure the expert is certified with the correct equipment. The law prohibits the discharge of R12 into the atmosphere, so the shop should retrieve the Freon with a refrigerant recovery system.
- 2). Drive home and secure the adapters to the existing ports on the system. The low-pressure port is on the line from the accumulator to the compressor and the high-pressure port is on the line from the compressor to the condenser. The adapters included in the conversion will only connect to the existing ports one way; the high-pressure adapter is the larger one, and the low-pressure adapter is the smaller one.
- 3). Start the car's engine and turn on the air conditioning. Set it to blow at the highest fan setting.
- 4). Puncture the can of Freon with the T-valve by attaching the hose included with the conversion kit. Let the Freon flow through the tube for five seconds to push out the air, then connect the end of the hose to the low-pressure fitting on the system.
- 5). Hold the can of coolant upright and let the Freon fill the system. Check that the air in the car is cold.
- 6). Fill the system with 90% of the amount of R12 the system originally contained. Check the owner's manual for the exact specification. If you don't have the manual, stop filling with Freon when the air begins to blowing cold. Over-filling the system could cause damage.
- 7). Twist the T-valve off and unscrew the tube from the adapter on the system. Keep the tube attached to the can so the Freon does not escape.
- 8). Cover the new adapters with plastic caps and place the R134a sticker in the engine compartment; both are included in the conversion kit.
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