How to Recharge Air Conditioning with Freon in Vehicles

by Contributing Writer

Most people want cold air when they are driving in warm weather. If the air conditioner in your Vehicles is blowing warm air, adding refrigerant to the system may correct the problem, as long as the components are working properly.

Under The Hood:

 How to Recharge Air Conditioning with Freon in an Acura Integra

Prepare for Recharging

Inspect your air conditioning lines for damage. Some auto parts stores have kits that will help you to find leaks in the system and possibly seal small leaks. If you see any visible damage, take your Integra to a professional to recharge the air conditioning system with Freon.

Locate the Low Pressure Side port. You can find this under the hood of the car. It will be near the front grill. When you are looking from left to right, the port will be almost directly in the center. Take off the port cap and set it aside.

Determine if your car uses R134 or R12 Freon. R134 compatible models will have quick connect port valves. Models made before 1995 may use the old R12 Freon. If this is the case, you must have your Integra's air conditioning system retrofitted to use R134 Freon.

Check the air conditioning system pressure using an auto air pressure gauge. Keep in mind that the car should be on with the air conditioner running full blast. If the pressure is in the normal or high range, lack of Freon isn't the problem.

Recharge the System

Attach the refill kit hose to the connector on the Low Pressure Side of the air conditioning system. Make sure you follow the manufacturer's directions.

Open the valve on the refill hose slowly to allow the Freon to enter the air conditioning system. Keep in mind that it can take as long as 10 minutes to empty a single can of R134 into the system. Your car can hold a total of 27.4 oz. of Freon.

Close the valve on the refill hose and remove it from the Low Pressure Side port. Remember to put the cap back on the port.

Leave the air conditioner on for at least 30 minutes to allow the Freon to circulate through the entire air conditioning system.

Items you will need

  • Safety goggles

  • Gloves

  • Leak detection kit

  • Auto air pressure gauge

  • R134 recharge kit

 How to Recharge Air Conditioning with Freon in a Chevy Silverado

Look closely at the air conditioning lines to check for damage. You can use a leak detection kit to make it easier to find leaks. These are available at your local automotive store. If you see any visible damage, take your Silverado to a professional to recharge the air conditioning system with refrigerant. Find the Low Pressure Side service port. This is located on the line coming out of the compressor toward the engine block. Take off the black cap that is covering it.

Start your truck and turn on the air conditioner. Use the automotive air conditioner pressure gauge to check the Low Pressure Side pressure. In order to get the most accurate reading, you need to have the air on the coldest setting and the unit blowing as hard as possible.

Hook the refill hose up to the connector on the Low Pressure Side of the air conditioning system. The Low Pressure Side connector is smaller than the High Pressure Side connector. Because the connectors are different sizes, the refill kit hose should fit only on the Low Pressure Side port.

Hold the can upright and slowly turn the valve. Keep in mind that it may take 10 minutes or longer for the can to empty into your system.

Close the valve on the refill hose when the pressure is within the normal range and remove the hose from the Low Pressure Side connector port.

Replace the cap on the Low Pressure Side connector when you are finished recharging your air conditioner.

Leave the Silverado running for 20 minutes so the refrigerant can circulate evenly through the entire system.

Items you will need

  • Safety glasses

  • Gloves

  • Leak detection kit

  • Air conditioner pressure gauge

  • R134 air conditioner recharge kit

 How to Recharge Air Conditioning with Freon in a Hyundai Sonata

Check the air conditioning lines of your Hyundai Sonata for damage. Leak detection kits are available to help detect leaks and seal small ones. If you notice any leaks or damaged areas, you should replace or repair them before you recharge the system. Keep in mind that it is illegal to discharge refrigerant into the air. This includes refrigerant that leaks from a recharged system that you know leaks.

Find the Low Pressure Side port. This port is between the compressor and the firewall. It has a yellow or blue cap marked L or LOW. Take off the cap and put it aside. You will have to replace it later.

Look at the Low Pressure Side port connector to determine if the system is compatible with R134 refrigerant. If you see quick connect valves, it is R134 compatible and you can continue with the recharge. If you see screw on valves, the system takes R12 and you need to retrofit it to accept R134 because R12 and R134 are incompatible. Mixing the two may cause serious damage to the system.

Check the pressure on Low Pressure Side of the system using an automotive air conditioner pressure gauge. To do this, turn on the ignition and the air conditioner. It should be on the highest fan speed and lowest temperature to get an accurate pressure reading.

Add R134 refrigerant to the Low Pressure Side. Make sure you follow the directions on the kit. These will vary with different kits. Keep in mind that it may take more than one can to fully recharge the system. Make sure that you check the pressure often so you can be sure to keep the pressure within safe limits.

Close the valve and remove the refill kit or can from the port valve. Follow the manufacturer's directions when you do this. Make sure that you replace the cap on the Low Pressure Side port valve.

Give the refrigerant time to circulate by leaving the engine running and the air conditioner on for at least 15 minutes.

Items you will need

  • Safety glasses

  • Gloves

  • Leak detection kit

  • Pressure gauge

  • R134 refill kit

 How to Recharge Air Conditioning with Freon in a Mitsubishi Eclipse

Look at the air conditioning system for signs of damage. Fix any damaged or leaking areas. While you are doing this, keep an eye open for the Low Pressure Side (LPS) service port. This will be on the larger line coming out of the compressor. It will have a black cap on it. Remove the cap and set it aside.

Determine if the system is R134 refrigerant compatible. If you see a quick connect port on the LPS, the system is R134 compatible and you can continue with the recharge. R12 systems have screw type connectors. If you see this, retrofit the system before you continue. R12 and R134 are incompatible. Mixing them will damage the air conditioning system.

Check the pressure using an auto air conditioner pressure gauge. You will have to have the air conditioner on a cold enough setting for the compressor to turn on in order to get an accurate reading. If the reading is at least 25 psi, there is enough refrigerant in the system and you should take your Eclipse to a professional for service.

Attach the refill kit hose according to the manufacturer's directions. Release the refrigerant into the system. It can take as long as 10 minutes to fully empty the can of refrigerant.

Know that your car can safely hold 26.7 oz. of refrigerant, so you may need to add more than one can of refrigerant. Keep in mind that the pressure should stay below 45 psi so you need to check the pressure frequently.

Take the refill kit hose off according to the kit instructions. Clean the port with a clean paper towel. Replace the cap on the LPS. Refrigerant can leak out of the port if you forget to replace the cap.

Circulate the refrigerant by leaving your Mitsubishi Eclipse running with the air conditioner going full blast for 15 minutes.

Items you will need

  • Gloves

  • Protective eye glasses

  • Pressure gauge

  • R134 refill kit

 How to Recharge Air Conditioning with Freon in a Jeep Grand Cherokee

Inspect the lines for signs of extreme wear or damage. There are some leak detection kits available at most auto parts stores that will help you to see leaks and possibly seal small leaks. If you notice any damage or leaks, you need to fix them before you try to recharge the system.

Find the Low Pressure Side port of the air conditioner. On most Jeep Grand Cherokee SUVs, this will be located near the front grill on the driver side of the engine. In some cases, you may find it near the firewall. This depends on the engine size and year model. The cap on the LPS port is blue or yellow and marked L. Remove this cap.

Look at the connector valve to determine if the system is R134 or R12 compatible in models made in or before 1995. If the valve is a quick connect valve, the system is R134 compatible and you may proceed safely with the recharge. If you see screw type connector, the system is R12 compatible and you must retrofit it before you can add R134 refrigerant.

Turn on the engine and the air conditioner. You need to put it on the coldest setting and highest fan speed. This will make all of the system components work which will circulate the refrigerant and allow you to get accurate pressure readings.

Check the pressure on the Low Pressure Side. To do this, get an automotive pressure gauge from the auto parts store. Read and follow the manufacturer's directions. These may vary slightly for each brand or type of gauge.

Connect the can of R134 to the LPS according to the kit directions. There are a few different types of kits, including quick charge, direct charge and trigger charge. Allow the system to suction the refrigerant out of the can. In some cases, this can take as long as 10 minutes. You may need to add more than one can of refrigerant to fully recharge the system.

Disconnect the refill kit according to the instructions. Keep in mind that you should leave the SUV running with the air conditioner on for at least half an hour to allow the refrigerant to fully circulate through the whole system.

Items you will need

  • Protective eye wear

  • Gloves

  • Leak detection kit

  • Pressure gauge

  • R134 refill kit