How To Put Freon In Car Air Conditioner? [Full Guide]

The worst thing to have on a hot day in Texas is a conked-off air conditioner. Refrigerant leaks are the most common cause for the failure of an air conditioner of a car. But do you know that you don’t always have to rely on an ac technician for refiling the system? You can also do it on your own in your driveway. 

Recharging the system is an easy DIY task and takes just about 15 minutes. By following basic precautions, you can easily learn how to put freon in car air conditioners through this article. 

Things To Look For Before Putting Freon In

To make repairs, inspect your system for minor leaks. Using a UV light, all valves and crosspoints in the system are to be examined. Due to its ozone-damaging qualities, R-12 has been phased out from the 1995 model year. You may have R-12 or R-134 if you have a vehicle manufactured between 1992 and 1995.

If your car has R-12, it must be converted to the R-134, which is the best work to complete for an A/C mechanic. Also, this task requires a good amount of concentration, so do it only if it is within your capabilities. 

How To Put Freon In Car Air Conditioner?

You can recharge your air conditioner in only a few minutes, and it is cheap. This is one of the fastest and easiest things to complete, but it can also cause harm to the air conditioning system if it is done incorrectly. Follow these steps to do it properly-

1. Find Recharging Ports Of The Ac System

Find your A/C system’s low-side recharge port next. There will be a dryer/receiver, which is a huge aluminum container, on the large tube between the compressor. In case of difficulties locating it, consult the service handbook. Located on the low-pressure side of the system on the coolant fill port.

It has an L-piece on the top of a little plastic cover. Remove this cap to disclose the port. Make sure the port is clean of any debris. When learning how to put freon in car air conditioner, remember always L-side port is used. 

2. Evacuate All The Air From Ac Lines

You should first vacuum the system with a vacuum pump or an Ac service machine with the help of an Ac manifold set. With this, moisture and dust are removed within the AC car system. You must install your Access Valve on both the low and high sides of the AC system. This helps you to suction without a pump in your AC system.

Pull deep vacuum at least for five to forty-five minutes with a vacuum pump connected. An aspiration of approximately 500 microns or 29,92 hg.

3. Check For Ac System Leaks

Leave the unit in a state of vacuum for few minutes to see any movement on the guage. If it cannot hold vacuum, then look for leaks and get it repaired. Check the small leak system if you have purchased UV dye as part of the kit, so repairs can be done if necessary. Using a UV pen, all valves and crosspoints in the system will be examined. 

4. Attach Refrigerant Can And Start Dispensing The Freon

Screw the distributor hose onto the low-side port. Join the lower side port with the slip ring coupler pulled back and press it on and released the ring. Next, turn the A/C system and verify the reading of the gauge. It is necessary that the compressor clutch spin the front of the compressor.

If the compressor pressure is lower than 20 psi, wait till some freon is filled. Make sure that you shake the boot every first 3-4 seconds.

5. Keep In Mind The Pressure Chart

Refer to the pressure chart for the right system pressure in the refrigerant instructions, it is an important step in learning how to put freon in car air conditioner. Keep the coolant and the pressure check until you achieve the required level. The instructions required 45-55 psi with an ambient temperature of 85 degrees.

Make sure the system is not overpressured. If the container is empty, twist it before removal to distribute the rest of the oil.

6. After Recharging Procedure

Once maximum coolness has been achieved and the engine and system are still operating, The connector collar has to be released to remove the kit. The pressure will go down if you shut down the engine and allow the system to neutralize. Pull the valve retention ring upwards on the valve. This releases the connector and automatically closes the service port.

How To Keep Car Ac System Healthy?

The blockage in air filters and AC condensers that limit airflow across cooling coils is one of the most common problems. Make sure that every month, without fail, the condenser is washed carefully with water. Not only will this help remove dirt from the normally unattainable sections, but it will also help maintain superior refreshments, so that you may be relieved in summer.

The AC air filter, situated underneath the dashboard in most cars, should be completely cleaned with water or, if necessary, replaced. Make sure you clean up the filter during regular maintenance. Replace it if it has gone too bad.

Costs Involved In Freon Recharge

Presuming that your car ac is healthy and you just need a top-up, then a can of freon will cost under 50$. But if you have some leakage in the system, then a professional repair can go up to 500$. If you have an older R-12 system, then it will cost around 200$ to convert it. 

If any major component has gone bad like a condenser or a compressor, then the cost will increase, and depending on the car make and model, it can cost up to 500$.


To conclude, yes it is easy to learn how to put freon in car air conditioner. But be very careful when you go about doing this business, you can easily cause severe injuries if you accidentally connect to the high side port of the system, so be very careful.

If you still have any doubts, then comment down below. 

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