How to Put Freon in Vehicles

by Contributing Writer; Updated June 12, 2017

There are some features in you car that you probably take Vehicles granted. If it's a hot summer day, a flick of a switch will get the air conditioner running. But what if you turn on your air conditioner and only feel the fan? The problem is probably a lack of freon in the air conditioning system. Adding freon to your car is not as hard as it may seem. You'll just need to buy a can of this chemical cooling agent from your local auto store and know where to add it when you lift up the hood to your Vehicles.

Under The Hood:

 How to Put Freon in an RV Air Conditioner

Identify the correct refrigerant type as marked on the air conditioning unit's specification tag. Use only the type of refrigerant labeled.

Remove the air conditioner's cover. They usually have four to six bolts found along a rib near the RV's roof. Use the correct size socket to remove the bolts. Lift the cover straight up to avoid damaging the condensing coil.

Remove the RV air conditioner's refrigerant service port cap on the suction side with an adjustable wrench. The suction side has the large copper tube running from the compressor down into the RV, which eventually goes to the evaporator coil. The smaller copper tube runs from the compressor to the exposed condensing coil.

Connect the suction side hose on a set of refrigeration manifold gauges to the service port. The hose will screw onto the service port and release a needle valve in the port. The suction side gauge, found on the left, has pressure and temperature readings for several different types of refrigerants.

Connect a bottle of the correct refrigerant to the middle hose on the refrigerant gauges. Open the bottle's valve. Purge the middle hose by quickly opening and closing the right hand valve on the manifold.

Turn the RV air conditioner on and set the thermostat to its coldest setting. Check the ambient air temperature in the RV in a spot away from the air conditioning vents.

Use the pressure-temperature chart located on the RV air conditioner's lid to find the correct refrigerant pressure for the ambient air. The chart will have a row of temperature readings printed next to a row of corresponding refrigerant pressures.

Open the suction side valve on the manifold for 60 seconds. This releases refrigerant into the system.

Check the suction side gauge pressure at least 60 seconds after closing the valve. Add refrigerant as needed.

Close the refrigerant bottle's valve and remove the charging hose. Disconnect the hose from the service port and reinstall the cap. Carefully slide the air conditioner's lid into place and secure it with the bolts.

Items you will need

  • Socket set

  • Adjustable wrench

  • Refrigerant manifold gauges

  • Thermometer

 How to Put Freon in a Porsche Auto Air Conditioner

Open the Porsche's engine compartment, and locate the vehicle's aluminum air conditioning pipes. You will find two sets of pipes of differing diameter. You will need to find the thicker pipe connected with the compressor. It will feature a low pressure service port with a blue or black covering.

Pull the covering off of the low pressure service connection. Fit a Freon recharging kit to the low side connection.

Set the recharging kit down on top of the engine. It needs to remain far away from any engine parts that will move.

Start the porsche's engine. Start the air conditioner with the air temperature on the lowest degree. Switch the Porsche's air blower to the highest setting.

Exit the Porsche and open all of the doors. Then, return to the engine compartment and the recharging kit.

Release the Freon into the Porsche's air conditioner. Rotate the kit's nozzle downwards completely. Allow exactly 60 seconds of Freon to rush into the pipes and then close off nozzle by turning it upwards.

Wait 60 seconds and allow the air conditioner's blower to circulate the Freon through the system. Continue to add Freon in 60 seconds of charge with 60 seconds of circulation.

Monitor the gauge on top of the recharging kit. This gauge measures system pressure and will tell you when the system is charged. There are two other ways to check if the process is completed. The Porsche's air conditioners will be evenly cold. If you place a thermometer into the air conditioner's central duct, you will be able to monitor the internal air temperature. A charged systems will measure at 40 degrees. If the you are recharging the Porsche in hot weather, the system could become consistent anywhere between 40 and 60 degrees.

Detach the Recharge kit and fit the covering back onto the low side pressure connection. Let the engine and the air conditioner run for another 15 minutes. That will allow the blower to fully circulate through the entire system.

Items you will need

  • Freon recharge kit

  • Gloves

  • Glasses

  • Thermometer

 How to Put Freon in My 2002 Pontiac Grand Am

Park the vehicle on a flat, even surface. Engage the vehicle's parking brake and open its hood.

Locate the low pressure air conditioning line (in Pontiac vehicles, this line is marked with a blue cap). Unscrew the cap and set it aside.

Screw the air conditioner pressure gauge hose labeled "low pressure" onto the vehicle's low pressure valve. The Grand Am's R134a system prevents you from attaching the wrong hose to the wrong valve.

Attach the vacuum pump to the center hose on the air conditioning gauges. Turn the pump on to suck all of the air out of the system. The low pressure gauge should now read "Vacuum" and have a pressure of roughly -30 PSI. Let the vacuum run for at least one half hour to clear all of the moisture out of the system. When it is finished, disconnect the vacuum from the center line.

Connect the freon tank to the center hose on the air conditioning gauges. Open the freon tank's valve and slowly loosen the nut on the center hose until it hisses. Once it hisses, tighten it back down again. This will purge the air from the line.

Place the tank on the refrigerant scale. Turn the car on and turn its air conditioner to its coldest and highest settings.

Open the low pressure valve on the low pressure side of the air conditioning gauge to begin filling the vehicle. Fill the vehicle until the scale reads 1.4 pounds. Once it reaches this weight, close the low pressure valve.

Close the valve on the freon tank and remove the hose. Remove the hose from the vehicle's low pressure valve and replace the blue cap. Let the engine run for at least twenty minutes before you shut it off.

Items you will need

  • Air conditioning gauges

  • Vacuum pump

  • Freon tank

  • Refrigerant scale

 How to Put Freon in My PT Cruiser

Turn on your PT Cruiser and turn the air conditioner to the high setting.

Open up the hood and locate the service fittings on the AC lines. You are specifically looking for the low-side fitting. It is located between the accumulator and the compressor. If you're having problems locating it, check your owner's manual. The low-side fitting should be easy to identify. It is the only fitting that will fit your freon can.

Turn the valve on your freon can for several seconds to release the air inside. Close it back up afterward.

Attach the freon fitting to the low-side fitting, and turn the valve on the freon can. This will feed freon from the can to your AC system. Do this while holding the freon can upright.

Remove the freon can from the low-side fitting and close all valves when the can has been used. Your AC system in your PT Cruiser should be as good as new.

Items you will need

  • Freon

  • Gloves

  • Goggles

 How to Put Freon in a 1999 Ford F-150 Pickup

Attach the A/C gauge set to the service ports in your 1999 F-150. The high pressure line service port is located on the passenger side of the truck, near the coolant reservoir, and is protected by a black plastic cover. The low pressure side service port is located on the accumulator near the passenger side of the firewall and is also protected by a plastic cap. In this truck, the ports are different sizes, and the gauge set can only be installed one way. Pull back on the quick-disconnect ring on the red hose fitting and snap it onto the high pressure port. Install the blue, low pressure hose, in the same way, on the low pressure port.

Set the A/C controls on the dash to max A/C and medium blower speed. Start the engine and observe the gauge readings. It may take a few minutes for the gauge readings to stabilize. The low pressure (blue) gauge should read 40 PSI, and the high pressure gauge (red) should read 350 PSI in a fully charged system.

Screw a can of freon to the can tap on the end of the yellow service hose on the A/C gauge set. Turn the wing screw on the tap all the way in to pierce the top of the can. Unscrew the wing screw to open the can. Open the low pressure side (blue) valve on the gauge set and allow the can of refrigerant to flow into the system. Close the valve when the can is empty and observe the gauge readings. Add additional cans of refrigerant, as needed, to fill the system until the pressures are between 40 and 350 PSI.

Turn the engine off and wait for a few minutes for the pressures in the system to drop. This will prevent damage to the service ports on the truck. Reinstall the plastic caps on the ports.

Items you will need

  • A/C gauge set

  • R-134A refrigerant

 How to Put Freon in an RV Rooftop Air Conditioner

Release and lift away the rooftop air conditioner's outer shroud. The shroud will be held in place by a series of fasteners around its lower rim. Use a screwdriver or socket or wrench, as determined by the fasteners used by the manufacturer. When lifting away the case, take care not to contact the fragile equipment inside.

Inspect the machinery to learn whether there is a refrigerant port. If there is, it will be located on the side of the machine that contains the larger of two copper tubes, which runs from the compressor to the RV's interior and the evaporator coil. This is called the "suction" side of the system.

Consult the manufacturer's literature or a data tag on the machine to determine which type of refrigerant is required. Older vehicles typically use R22, which is now expensive and difficult to source. Newer vehicles use a number of different types. Buy a recharge kit of the appropriate refrigerant.

Use your thermometer to measure the ambient temperature inside the RV. Locate the air conditioner's chart, which will typically be fixed inside the shroud. The chart will have a series of temperatures noted alongside a series of optimum refrigerant pressures, one for each temperature specified.

Attach the manifold gauge hose clearly labeled as being for the suction side to the port, usually the left-hand hose. Attach it by screwing the female hose end in a clockwise direction onto the male threads of the port.

Switch the air conditioner on by activate it by dropping the thermostat to its coldest setting.

Consult the gauge clearly labeled as being for the suction side to confirm that a top-up or recharge is necessary. Do this by reading the pressure of the refrigerant inside the air conditioner and comparing it to the chart's ambient temperature figure, which matches your reading from inside the RV. If the refrigerant pressure is less than optimum for the temperature measured inside your RV, it is necessary to top up or recharge the system.

Attach a container of the prescribed refrigerant to the hose clearly labeled as being for this purpose, usually the central hose. Purge the gauges by briefly opening and closing the valve clearly labeled for this purpose, usually the right-hand valve.

Open the clearly labeled charge valve and allow Freon to enter the air conditioner for one minute. Close the valve and wait a further minute before rechecking the gauge. Repeat this process as necessary until the refrigerant pressure reaches the level specified as optimum for the temperature measured inside your RV.

Items you will need

  • Air conditioner recharge kit

  • Manifold refrigerant gauge set

  • Screwdriver OR

  • Socket OR

  • Wrench

 How to Put Freon in a Honda Element

Ensure that your Element is parked on a flat surface. Engage the emergency brake. Move your gear shifter to an appropriate setting. Place it in park if your Element is automatic, and place it in neutral, if the Element is a standard transmission.

Open the Element's hood and locate the air conditioner's metal tubes. These aluminum pipes will feature two pressurized connection ports. The high side connection is used mainly for maintaining pressure within the Element's air conditioning. You do not need to use it for this task, and the R134a kit will not even fit this port. Remove the dust cap from the low side connection and attach your R134a Freon kit's service hose.

Find a safe place to temporarily set your kit down. Within the Element's engine compartment, the kit should not be anywhere near something that will shift, shake or jostle it, like any of the Element's belts.

Take a seat behind your Element's steering wheel. Start the engine and warm it to it's standard running temperature. Then, set and run your car's air conditioner at its highest air-blowing capacity. Also, set the air conditioner on the coldest temperature setting. Later, this will help you take an accurate reading of the system's internal temperature. Let the air condition run for five minutes.

Exit the Element and open all the doors. The R134a Freon you are about to add needs to fully circulate within the system, and opening the doors will help ensure the system doesn't accidentally turn itself off, since the air cannot collect in a closed passenger compartment.

Open the R134a canister by turning the kit's nozzle all the way down. The nozzle's internal needle will puncture the can's seal. You will hear gas noises akin to a "rush." This is only the Freon leaving the can, traveling through the service hose and entering the air conditioner's aluminum pipes.

Allow a minute of charge before shutting off the can's nozzle. Allow a minute to pass before adding further charges of Freon. Waiting will allow the R134a Freon to fully circulate. Monitor the kit's pressure gauges during charging and resting periods.

Stick a thermometer into the Element's central air conditioning duct. Since the engine is still running, the thermometer will give you a more accurate temperature reading than Element's dashboard instrument cluster. Watch the temperature drop on the thermometer. The process is complete when the thermometer reads 40 degrees.

Remove the kit's servicing hose from the air conditioner's low side connection. Replace the connection's dust cover. Shut the hood over the engine compartment. Let the vehicle idle for another five to 10 minutes, so the Freon can evenly distribute itself throughout the air conditioning system. Then, shut off the air conditioner and the Element's engine.

Items you will need

  • R134a recharge kit

  • Thermometer

  • Gloves

  • Glasses

 How to Put Freon in a 2002 Chevy Trailblazer

Park the TrailBlazer on a level surface and turn off its engine. Allow a few minutes to pass to let the engine cool down. This will give a proper reading of the coolant tank.

Open the hood and locate the engine coolant tank in the far corner closest to the passenger's side. The tank will have "DEX-COOL" printed on the cap.

Check the coolant level by reading the indicators on the side of the coolant tank. If the coolant lies below the FULL COLD mark, you will need to add more.

Loosen the cap (but do not remove it) to allow excess steam to escape from the tank slowly, avoiding potential steam burns. Remove the cap when there is no more steam.

Pour the coolant into the tank until it reaches the FULL COLD mark. Replace the cap on the tank and close the hood.

Items you will need

  • Freon/coolant

 How to Put Freon in a 1994 Ford Explorer

Start the engine, and let it run while you are filling your cooling system. Place the hose and gauge on the bottle of R-134a.

Open the hood of the Explorer, and find the low-pressure fitting on the accumulator. There are two fittings: a low- and a high-pressure fitting. The low-pressure fitting is on the accumulator at the back of the engine compartment and on the passenger's side. The high-pressure fitting is near the battery on the driver's side. The low-pressure fitting is smaller than the high-pressure fitting.

Listen to engine to hear whether the compressor is running. If it is not running, and does not start running as you fill the system with refrigerant, you could pressurize your system too much and damage your air conditioner.

Take the cap off the low-pressure fitting, and put it in a safe place. Shake the bottle of refrigerant for one minute, and place the end of the hose on the low-pressure fitting. Press the button on the can to release the refrigerant and fill your system.

Watch the gauge, and do not overfill the system. If the compressor was not on, listen for it to engage. If the compressor does not engage, stop filling the system with refrigerant, and take your car to a mechanic.

Take the hose off the low-pressure fitting when you have filled the system and the gauge reads "Full". Replace the cap on the low-pressure fitting, and shut the hood.

Items you will need

  • Can of R-134a refrigerant with hose and gauge

 How to Put Freon in a Toyota

Open the Toyota's hood and locate the low side pressurized service port. It will be found on an aluminum pipe running from the vehicle's condenser. Remove the cap from this port.

Fit the Freon recharging kit's coupler onto the service port. However, do not turn the valve atop the kit. If the coupler does not fit the service port, then you have the wrong recharging kit. An R-12 kit will not fit an R-134a system and vice-versa.

Set the kit down, but ensure it is nowhere near movable engine parts.

Walk around the Toyota and roll down all the windows. This must be done, as it will keep the Toyota's air-conditioner from accidentally turning off during the refilling process.

Start the Toyota's engine and warm it to its normal operating temperature.

Run the air-conditioner at its lowest setting. Give it a few minutes to get as cold as it can.

Return to the Toyota's engine and your recharging kit. Turn the handle atop the Freon container all the way down. This will crack the containers seal and let the Freon rush into the Toyota's air-conditioner.

Monitor the pressure gauge on the canister. Turn the handle on top of the kit upwards and shut off the flow of Freon once 60 seconds has elapsed.

Let 60 seconds of "not-charging" pass. This will let the recently added Freon circulate through the Toyota's air-conditioning system.

Continue to monitor the pressure gauges while adding Freon in 60 second spurts. The kit's gauge will tell you when the process is complete. If you need a second opinion, place a thermometer into the system's central duct. The systems internal temperature will be around 40 degrees during normal weather and between 40 and 60 during extremely hot weather.

Remove the kit's coupler and hose from the low-side pressurized service port. Leave the air-conditioner running, and give the Freon about 10 minutes to fully circulate. Then turn the engine off.

Items you will need

  • R-12 or R-134a refilling kit

  • Safety glasses

  • Gloves

About the Author

This article was written by the It Still Runs team, copy edited and fact checked through a multi-point auditing system, in efforts to ensure our readers only receive the best information. To submit your questions or ideas, or to simply learn more about It Still Runs, contact us.