How to Recharge the Freon on Vehicles

by Contributing Writer; Updated June 12, 2017

Recharging the freon in your Vehicles is also known as recharging the air conditioner. This is a part of standard auto maintenance. Over time, freon levels may drop and cause the air conditioner to lose power. Therefore, cold air will stop blowing through the vents in your Vehicles. The process of charging an air conditioner is pretty straightforward and similar Vehicles most makes, models and years of automobiles. With a few simple steps, your AC can be functioning normally and ready Vehicles any hot day.

Under The Hood:

 How to Recharge the Freon on a 1986 Nissan Pickup

Pop your 1986 Nissan truck's hood. In the engine compartment, you will find a series of metal tubes. These aluminum pipes will contain a high side and low side connection point. Your R134a kit's servicing hose will not fit the high side connection point. It will, however, fit the low side connection point. Remove the low side's connector's cap and attach your kit's servicing hose.

Leave the kit in a safe place. It should not be next to anything that will jar or jostle it once the Nissan's engine is started. This includes both fans and belts.

Start the Nissan's engine and allow it to idle. Watch the vehicle's temperature rise on the instrument cluster's temperature gauge. Once the truck is warmed up, turn on the air conditioner to its coldest and strongest-blowing settings. This will help you take accurate air temperature readings inside the system.

Place a thermometer into one of the Nissan pick-up's air conditioner vents. Watch the thermometer's readings as the air conditioner's internal temperature drops. It may not drop that far, depending on how much R134a is left in the system. If the Freon levels are completely depleted, the temperature may not drop at all. Once the system's temperature becomes consistent, remove the thermometer.

Open both the driver and passenger-side doors before returning to the Nissan's engine. This will keep air from building up within the Nissan's passenger compartment. As a result, it will also keep the air conditioner from accidentally switching off.

Turn the nozzle on top of the R134a canister. The nozzle will open the can's seal, allowing the Freon to flow into the air conditioner's metal pipes.

Let the Freon flow for a minute and then close the nozzle. This will let you read the kit's pressure gauge, and more importantly, it will allow the Freon to completely travel through the system, stabilizing under the system's internal pressure. Add more Freon in increments, with at least a minute between each installment.

Place your thermometer into the Nissan truck's central air conditioning duct. As you add increments of Freon, watch the thermometer's readings. The system's internal temperature will begin to fall. A fully charged system runs at 40 degrees while running at full blast.

Shut the nozzle at the top of the R134a canister tightly once you have finished recharging. Remove the kit's servicing hose from the air conditioning's low side connector. Replace the low side connector's covering and shut the Nissan truck's hood.

Allow the engine and air conditioner run for another five to 10 minutes. This will ensure that the newly added Freon isn't concentrated into one part of the air conditioning system.

Items you will need

  • Thermometer

  • R134a kit

  • Gloves

  • Safety glasses

 How to Recharge Freon on a 1997 Ford F150

Wait at least 30 minutes after the last drive before working on the air conditioner. The engine will need to be cool.

Find the service knobs on the AC. The high-side knob is on the hose connecting the condenser to the compressor. The low-side knob is on the hose running from the compressor to the accumulator.

Connect the service hose to the can of refrigerant. Specific instructions for your brand of refrigerant will be located on the can. The instructions are generally the same from brand to brand, but be careful to read the instructions just in case there is some difference.

Turn the service hose valve to open it. The pressure that is released when the coolant and air come out will open the can of refrigerant. Close the valve once the can is broken open.

Attach the service hose to the low-side knob. The can of refrigerant needs to be held in an upright position while doing this.

Start your auto's engine.

Turn your air conditioning on to the highest possible setting.

Open the service valve. This will allow the refrigerant to enter the air conditioner.

Place your hand near the interior air conditioner vents of the F150. Make sure the air is cold. Continue to run the automobile until the can of refrigerant is empty. The air will not get any colder when the can is finally empty. Instead, it will remain at a steady cold temperature.

Close the service valve.

Turn the F150's engine off.

Remove the can from the service knob.

Items you will need

  • R134a refrigerant

 How to Recharge the Freon in a 2001 Jeep

Open the hood and locate the air conditioning unit. The unit is located near the windshield, on the left side of the vehicle. It is comprised of an accumulator, a compressor and a condenser.

Locate the low side service fitting on the hose between the accumulator and the compressor. If in doubt, compare it to the high side service fitting on the hose between the compressor and the condenser: The low side fitting has a smaller diameter.

Connect the recharge service hose to the can of R134 refrigerant. Twist the valve on the hose to puncture the can. Slowly release the valve--just enough to let the hose fill with freon vapor--then tighten the valve. This action forces out the air accumulated inside the hose, which can cause your air conditioner to run improperly.

Connect the free end of the service hose to the low side fitting. The hose will only fit on the low side fitting, so you do not have to worry about accidentally connecting it to the high side fitting.

Turn the engine on. Turn the air conditioner control of your 2001 Jeep to "Max A/C."

Hold the can of R134A refrigerant upright and open the valve. Once the compressor starts, it will draw the freon vapor into the air conditioning unit. You will notice that the can becomes cold. Allow at least ten minutes for the air conditioner to charge.

Check to see if the air conditioner is blowing cold air into the cabin of the Jeep. Shut the vehicle off. Disconnect the recharge service hose and close the hood.

Items you will need

  • R134A refrigerant canister

  • Air conditioner recharge service hose

 How to Recharge Freon in a 2001 Chevrolet Impala

Assemble the R134a recharging kit. While you are attaching the hose to the Freon canister, exercise caution while turning the valve atop the canister. Turning this valve too far down will puncture the canister's seal and prematurely let the R134a rush out.

Locate the low side port within the 2001 Chevy Impala's engine compartment. This port will have a dust cap, and it can be found on the air conditioning system's aluminum tubes. Attach the hose to this port and find a safe place to rest the R134 recharging kit. Do not set the kit on or near any belts, fans or engine parts that will move once the engine is cranked.

Climb behind the Impala's steering wheel and crank the engine. Let the engine's temperature rise to it's usual running level. Then turn on the air conditioning. Place a thermometer into an air conditioning vent and watch the temperature drop. Once it reaches its lowest point, exit the Impala. Leave the door open,

Turn the valve atop the recharging kit's canister and let the R134a rush into the Impala's air conditioning system. Close the valve periodically to monitor the gauges. If the R134 canister becomes too cold to handle, wrap it in a towel. Allow at least a minute between charges into the system. This will allow the system to stabilize.

Place a thermometer into an air conditioning duct and watch the system's temperature steadily drop. A charged system will level off at 40 degrees. You will notice the process nearing completion once the air conditioning system's aluminum tubing becomes uniformly cold.

Close the valve atop the canister once system is charged. Do this even if the canister is depleted. Do not overfill the system as that can cause damage. Remove the hose from the low side port. Close the engine compartment and shut off both the Impala's air conditioning and engine.

Refrain from discharging excess Freon into the atmosphere. You can always used the left over R134a later. Leave the hose, gauge and valve attached to the can. Store the kit in a closet where there are no abrupt fluctuations in temperature. Keep the kit standing straight up and do not store any recharging kit by laying it on its side.

Items you will need

  • Thermometer

  • Safety goggles

  • R134a recharge kit

 How to Recharge the Freon in a Toyota Tacoma

Run warm water into a pail. Place a clean towel in the pail, and position the pail near the front of the Toyota Tacoma. This is an optional step, but you may need a warm towel later in the recharging process.

Assemble the recharging kit by attaching the hose to the freon canister. The hose attaches to the top of the canister and care must be taken while doing this. The kit's valve has a stem that will puncture the canister's seal if turned down all the way, and that would prematurely release the freon.

Prop open the hood of the Tacoma. Attach the kit's hose to the Tacoma's low-side port. This port will be located on aluminum tubing withing the air-conditioning system. There is a high-side port just above it, which needs to be left alone. The kit will not fit onto the high-side port.

Place the kit in a location that is not near any components that will move when the Tacoma's engine is running. This includes fans and belts.

Start the Tacoma's engine and allow it to warm to its normal running temperature.

Place a thermometer in an air-conditioning vent and turn the Tacoma's air conditioner on at maximum power. This includes the highest setting for blowing force, and the coldest setting for temperature. Monitor the thermometer and remove it after the system reaches its coldest temperature.

Leave the Tacoma's doors open when you return to the recharging kit. This will ensure that the air conditioner keeps running during the recharging process.

Put on the safety glasses and gloves. Pick up the recharging kit and turn down the valve atop the canister. You will hear a rushing-gas sound as the freon charges into the air-conditioning system. Periodically close the valve to monitor the kit's gauges. Wait a minute or two before adding new charges into the system. This will allow the system to stabilize between charges. The freon canister may become cold in your hands, and you may need to use the warm towel that you have kept handy.

Place your thermometer in an air-conditioning duct and monitor the temperature within the system. A charged system should cool to 40 degrees. You will also notice all of the aluminum piping becoming cold.

Turn the valve atop the canister and shut off the flow of freon once the system is charged. Remove the hose from the low-side port and turn off the air-conditioning system and the Tacoma's engine.

Store leftover freon in a place where air temperature remains constant. Do not dispose of excess freon by releasing it into the atmosphere. This means the hose and the gauge should remain attached to the canister, and the canister should be stored upright.

Items you will need

  • Freon recharging kit

  • Safety glasses

  • Gloves

  • Warm towel (optional)

 How to Recharge Freon in a GMC Sierra Truck

Start the engine and turn on the air conditioner; the charging process requires the compressor to be running.

Raise the hood and locate a canister wrapped in silver insulation at the back passenger's side of the engine -- this is the air conditioning accumulator. Remove the dust cap marked "L" from the charging port that runs over the accumulator.

Place the valve on the recharge kit onto the top of the refrigerant can and turn the valve's handle clockwise to draw out the stem and pierce the can.

Push the fitting from the kit's hose down onto the charging port. Turn the valve's handle back a little to retract the stem then listen as refrigerant flows from the can into the port.

Pull the hose fitting off of the charging port once the flow stops. Replace the dust cap and close the hood.

Turn the valve's handle counterclockwise and remove the hose from the empty refrigerant can. Discard the can but keep the hose to use next time.

Items you will need

  • Refrigerant recharge kit

  • Can of R-134a refrigerant

  • Protective eyewear