Updated at: 27-07-2023 - By: micdot

If your car’s air conditioner is overcharging, there are two people you should call. If you’re comfortable with mechanisms and technology, try it out first on your own before bringing it to a repair. If my opinion is important to you, please choose option two. You should definitely seek your mechanic for help. Coolant removal from a vehicle is only permitted by mechanics with appropriate training and certification in this area.

It’s not a good idea to do this if you’re just starting off. Doing so could result in punishment. Let your technician handle it, then. These chemicals are extremely dangerous and can pose a number of dangers to people and the environment if they are not handled appropriately. There are numerous parts and sections to an air conditioning system, making it difficult to comprehend. So, if you’re interested, I’ll provide information about it in this piece. In order to understand how your car’s air conditioning system works, let’s first learn how it works!

How Does A Car AC Work?

There are five key components in a car’s air conditioning system that allow it to cool. These are the parts:



Accumulator, receiver, or drying machine.


Expansion spool.

This system’s workhorse is the compressor. Low-pressure gas enters the compressor, where it is compressed into high-pressure gas before being discharged. The condenser receives this gas after it has been discharged. Condenser permits cool air to flow over the sections and cools the high pressure and temperature gas, which then turns into a liquid. The high-pressure liquid then flows into the accumulator. Inside is a desiccant bag that wicks away water vapor. Filtration and absorption of moisture are necessary. If not, it poses a risk to the Freon or refrigerant and may cause contamination. Between the accumulator and expansion valve, there is a service port that can be used for high-side servicing.

Afterwards, the high-pressure liquid is pumped via the expansion valve (TXV). The high-pressure liquid can expand and become a low-pressure liquid with the help of this expansion valve. Flowing immediately into the evaporator is this low-pressure liquid. The low-pressure liquid begins to boil in the evaporator, where it is converted to a low-pressure gas.

Cooled and cooled air flows via your car’s dash vents thanks to the low-pressure gas chilling the evaporator. The expansion valve and compressor share the low-side service port. The low-pressure gas is then pumped back into the compressor for a subsequent cycle. compressor. As you can see, it works like this. TXV systems are also used in many vehicles. For efficient cooling, the TXV valve is employed. The sensor bulb for the TXV system is located right at the evaporator’s outlet. When the evaporator’s temperature and pressure changes, the flow of Freon through the expansion valve adjusts to match. the MOT (Maximum Operating Temperature) is set by using the TXV valve’s temperature to adjust the outlet’s temperature. Mechanics can then use a low-side gauge to charge your system through the low-side service port. Adding refrigerant causes the low-side pressure bar to increase until it reaches 35 PSI, which is the maximum operational pressure.

Even if the system is completely charged and the pressure is over 35 PSI, adding additional Freon or coolant will not result in a low reading. In order to get an accurate reading, you will need to connect a high-pressure gauge to the high-pressure service port. The overcharging and undercharging issues that may arise from using only one type of gauge are well-known. Having studied how the air conditioning system works, I’ll show you exactly how to fix your overcharged air conditioner!

How Do You Fix An Overcharged Car AC By Yourself?


The dangers of repairing an overcharged air conditioning unit outside should be taken into consideration when doing so. The Freon in your system is the primary reason of your air conditioner temporarily overcharging. A pressure gauge must be connected in order to be certain. It’s time to get your AC fixed if this gauge shows pressure in the ’60s or above. When the temperature drops, an overcharged AC works just fine, but when the temperature rises, the gas inside the AC compressor expands, resulting in overfilled situations. Using a garden hose, you can easily release the pressure that builds up when your air conditioner is running. Close the vent and attach the hose before attempting to release the pressure. After you’ve made sure it’s connected properly, carefully release the pressure. Wear strong fabric gloves when the gas comes out because it is extremely cold and can burn your hand. You should also put on a pair of goggles to protect your eyes from the sand, which can blind you if it gets in your eyes. Not in my nature. Consider adopting the necessary safety measures. To be clear, whatever you call this substance (Freon or coolant), it’s extremely dangerous to you and the environment. You can’t do it until you’re qualified, of course. This is a nefarious enterprise, and if you are detected, things will get a lot worse.

Having a mechanic do it is the second option, as they are well-equipped to handle this potentially hazardous activity.

How Do I Know If I Have An Overcharged Or Undercharged AC?

If your aircon is pelting you with hot air, there are two likely explanations. The ac system is undercharged and needs a charge. Initially. As a second matter of fact, it is experiencing overcharging issues. A low-side pressure gauge would be required for confirmation. Keep all the vents closed when you attach the hose to the outlet. A sudden change in pressure could indicate a lack of coolant or a problem with the vehicle’s cooling system. If you have a dual gauge or could purchase one, it would be preferable. However, you may still get by with a simple one-gauge system. You need to know the outside temperature to figure out what’s going on in there. Let go of the wheel, get out, and keep a close check on the odometer.

Even though your automobile is now off, this is a perfectly typical process of balancing low and high voltages. Do not be alarmed. After a few minutes of waiting, you’ll notice that the pointer has come to a complete stop. Static pressure is the term for this. Now that you know how cold it is outdoors, you can make some sense of this static pressure.

Static Pressure To Temperature

Now, if the temperature outside is somewhere in the 90s, the static pressure inside the system will be somewhere between 103 and 104 PSI, depending on the model. There is an indication of overcharging if you see the indicator at 130, which shows that the pressure inside the system is higher than the outside. Or, if your static pressure is only 71 PSI, which is lower than the outside temperature, you need to charge the system up. But if it’s in the 70s outside, there’s no need to do anything. If your air conditioner is overcharged or undercharged, this is the only method to tell. If you’d want to learn more, keep an eye out for the following quick tips on ac diagnostics:

Tips To Find An Overcharged AC

Failure of the engine

An increase in force.

This is not a pleasant experience.

An issue with the compressor.

How Should You Recharge Your Car AC?

How to Recharge Your Car's AC System (Fast and Easy) - YouTube

You’ll need certain tools to recharge your air conditioner. When it comes to the most difficult stage of the process, you need the right instruments to make it work. The following is required:

Gauges for the manifolds.

The vacuum pump.

Vacuum pump powered by an AC motor.

Assemblies of weighing devices (for weighing coolant).

Of course, coolant can be tapped.


Goggles and gloves must be worn at all times.

You’ll need refrigerant to refuel your air conditioner. If you open the hood and look at the plastic trim around the engine, you’ll be able to tell which product to use. There’s a tag on the car that tells you what kind of refrigerant it uses. 134a is the most often used refrigerant in automobiles. The amount of refrigerant you should apply will also be shown. That’s why we’ve included a scale in this section to help you figure just how much to add. The figures must be identical. Overcharging your air conditioner is a surefire way to damage it.

Step 1

To begin, turn on the vacuum pump and remove the air conditioning system’s moisture. AC systems can be severely damaged by water. That’s why it’s important to utilize a vacuum pump when you need to remove moisture from the air conditioner’s components. If you don’t, you’re wasting your time and putting your system at risk of being ruined by moisture in the near future.

Step 2

Recharging your air conditioner’s refrigerant is the next step, and it couldn’t be simpler. Isn’t that easy? There we go!

Surely you’ve already put your gloves on. Bring them back!

Recharging The AC System

First, connect the manifold gauges to your air conditioning system. It’s best to take your time and ensure the connection is safe. The next step is to ensure that all of the valves are closed. There are three hoses in a gauge set: one for coolant recharge, one for low-pressure and one for high-pressure and. The low and high-pressure hoses, on the other hand, only fit on their respective sides. You only have to push down, slide it across, and let go to join the hoses. Yes, that was a breeze. Make sure they don’t come undone after you attach them. The valves can now be opened. The vacuum cleaner is now at the ready. Your vacuum pump should be linked to the third hose. The only thing you need to do is tighten them by hand. Fortunately, the gaskets are already in place to accomplish the job. Again, stay away from tools like pliers and the like.

Make sure to have your system properly drained of any remaining refrigerant. Be mindful of the environment when using this type of refrigerant. Everything is linked and secure, now let’s turn on the vacuum pump. Pump it up for a few minutes and then shut it down again after you’re done. In the ac system, you will receive a vacuum reading. Wait an hour and then check the reading. You’re good to go, i.e., the ac system is totally sealed, if the reading value equals the prior reading and there’s no leakage.

How to Properly Recharge Your AC System - YouTube

Once you’re certain there aren’t any leaks, turn on the pump again and let it run for another 45 minutes. Open the valves again and turn on the vacuum. This is going to remove all the water from the system completely. For the next 456 minutes, you can go do anything else and then come back. Immediately after 45 minutes, turn off the vacuum and shut off the valves. Prior to adding refrigerant, you must add oil to your aircon system if you’ve replaced a main component of it. To learn more about what type of oil to use and how much oil to use, consult the label and user manual. When you’ve connected the adapter to the can of refrigerant, you’ll then be able to connect the line. Once the adapter is screwed in, the can will be punctured, and the screw will be in the closed position. Purge the system and you’re done. It’s important to first clear the line of any surplus gas. Go to the top of the unit and use a screwdriver to press down on the refrigerant until it leaks out.

Now that your automobile is running, adjust the air conditioning and the fan speed to the lowest setting. Ascertain the current temperature. Now get out of the car and turn the low-pressure side valve to the right. In order for the compressor to pull the refrigerant, the AC must be running. It’s easy to see that the low-pressure side is sucking up pressure, while the higher-pressure side is putting it on. As we add additional refrigerant, the higher side will rise. When you’re sure it’s empty, give it a good shake. It won’t take long at all. Plug in the second can as soon as the first one is finished. Make sure the valve is turned off and the can is replaced. Scale it up or down as needed. Add only the amount of refrigerant that is necessary. To finish, simply turn off all of the hoses and close the valves. The battery has been entirely replenished.

Frequently Asked Questions

Q 1. How Long Will My Car Ac Last?

Every two years, the vehicle’s air conditioning system must be refilled with fresh coolant.

Q 2. How Should I Maintain My Car AC So That It Lasts Longer?

How to keep your car’s air conditioner in good working order is as follows:

Once a week, give your air conditioner at least ten minutes of work.

Allow the defrost to work for 5-10 minutes after turning it on.

Don’t quit using your air conditioner simply because it’s cold outside.

Once every two years, recharge your car’s air conditioning system.

Service and recondition the system.

Q 3. Is Air Conditioning Different Than Climate Control?

There is a big difference between climate control and air-conditioning. When it comes to air conditioning, drivers have complete control over the pace and volume of the chilly air, whereas climate control regulates your car’s interior temperature.

What Is the Difference Between Climate Control and Air Conditioning |  YourMechanic Advice


How do you fix a faulty air conditioning unit in your car? Was your answer correct? Repairing the car’s air conditioner by a mechanic is the only option that is guaranteed to work. It’s possible to apply the strategy I’ve outlined above, but it’s not without risk. It’s best to get it mended by a professional if you care about yourself and don’t want to get into any difficulty. This can only be done by trained professionals. Because it is a dangerous chemical, this refrigerant should never be released into the environment. Handling coolants is no joke; it requires extreme caution and should never be done in your house or in an open location. Only a professional can remove your coolant if you’re experiencing any of these problems.