How To Find AC Leaks In Cars – The Easiest Way To Deal With This Issue

How To Find AC Leaks In Cars – The Easiest Way To Deal With This Issue

August 18, 2021 0 By CarGuy

Summertime has come and your AC system somehow doesn’t blow cold, you filled up with refrigerant and it worked but after a few days again it started to leak? You shouldn’t worry, we are going to teach you how to find AC leaks in cars. This is mandatory to know in order to stop your coolant from leaking.

Getting a leak in your AC system can be an extremely frustrating thing to deal with. Especially if you run your car during the summer. And you want to enjoy the cool air that your AC offers. But you can’t because it’s leaking!

Personally, I understand you very well and that’s why we are here to explain to you how to deal with these issues. Everything is fixable in cars. You just have to have the will and you will solve your issue. The fact that you are here looking for how to find AC leaks in cars tells a lot. And you want to have this problem sorted out no matter the effort.

In this article, we are going to explain to you exactly that, we will learn first how the air conditioning work and where to look for your leaks. This is important in order to know how to find AC leaks in cars. Then we are going to get all the symptoms connected to a leaky AC. And lastly, we are going to list the cost to fix this problem. So, without further ado, let’s dive into it.

How The AC System Works? In Order To Understand How To Find AC Leaks In Cars

The AC system is a simple circulating system. During the cooling process the gas that is inside changes shape into a liquid and then again to gas. Basically, every refrigeration unit works pretty much the same. But we are going to dissect it into small details. In order for you to have a better picture.

The AC system is made out of a cabin radiator, compressor, front condenser, piping, and low side service point and high side service points. The low side pressure valve or service point is used to refill the system with refrigerant.

All the magic begins when the air compressor starts working and compresses the gas. And then the gas comes out of the compressor heated up to 185 degrees Fahrenheit. Then the refrigerant gas travels to the condenser.

In this condenser, the refrigerant cools down and during its travel, it changes its structure into liquid. This liquid then travels to the front condenser that is located on the firewall.

But before it reaches the condenser the liquid has to be again transformed into gas. And for that purpose. Then this gas travels in the front condenser and cools the condenser down.

Then the fan in the car starts kicking and blows into this cool condenser and then spreads this cool air into the cabin.

After this process is done. The gas again returns to the compressor. Then again it’s getting compressed and liquified.

This is the simplest explanation, but what about how to find AC leaks in cars? Well, we are going to cover that a bit later in this article.

What Kind Of Refrigerant Does It use?

In the past Freon R-22 was used. But this refrigerant was discontinued due to the damaging effects on the ozone layer. Since 2004 many of the AC systems have switched to some ozone friendlier alternatives like the R-410A.

The R-410A can be found under many names and the most recognizable brand is Puron. This refrigerant is readily available across the country and can be found in many auto part stores.

But before getting a refrigerant, make sure that you get the right one for your car. Also, you have to get some refrigerant with reliable gauges. That will tell you exactly right the amount of refrigerant you are running in your vehicle. Because you don’t want to overfill the system.

If you overfill the system, you are going to lose performance, and also you can damage your air compressor and your AC will not work. Speaking of performance, let’s see the power requirements to run an AC in your car, before we dive into how to find AC leaks in cars.

How Much Power Does AC need To Work?

This is a good question. The AC is drawing power from your engine in order to spin the compressor. Many claim that this power requirement is only a few horsepower from your engine. But in reality, it’s much bigger.

In the instant that you turn on the AC, you are going to notice a loss of power from your engine. This power loss can be around 10-30 horsepower.

This will be especially notable if you are running a car that has a small displacement engine. Most cars that run V8 engines will not even feel the air conditioning system.

But a small engine will start to lose power and the car is going to become sluggish and will barely react to your gas input.

That’s why it is a good idea to consider when you are getting a new car if you are going to use the AC very often. If you do, stay away from small displacement engines and get a car with a bigger engine instead.

Also, it is worth noting that this power demand is going to affect your driving performance and could possibly drive you into an accident. Imagine that you need to pass a big truck on the road. You give the signal and start the overtaking procedure, but the car struggles to keep up with the truck. Then you have a car in front of you and you have nowhere to go. That is an instant tragedy.

That’s why it is worth keeping in mind the power demand of AC systems and make sure that you always have a good power rating. So, how to find AC leaks in cars? We are going to cover that after we cover the symptoms of a leaking AC system.

Symptoms Of A Leaking AC System

Like with every other component in our car. The AC when starts leaking and losing refrigerant shows some symptoms. And if the AC doesn’t work, we need to study these symptoms of leaking AC systems. Then based on that we need to learn how to find AC leaks in cars. In this chapter, we are going to cover all the symptoms of a leaking AC system. So, let’s begin.

  1. AC Doesn’t Turn On
  2. AC Doesn’t Blow Cold Air
  3. AC Loses Cooling Ability Shortly After Recharge

1. AC Doesn’t Turn On

If your AC does not turn on, you are probably having an empty or leaky system. The AC system is smart and can recognize if there is a lack of refrigerant in the system and will not going to power the compressor.

When you are having an issue like this and the AC does not like to power on. The best thing to do is to fill up the system with refrigerant. This refrigerant can be found in all the part stores around the country.

The downside of this method to recharge your system manually is the possibility of overcharging the system. Most of the kits are coming with unreliable gauges that don’t work. Or if you are inexperienced, you can overcharge the system by accident.

Then you will have to purge the AC system and release the extra gas. If you don’t, your AC will not going to blow cold air and your compressor is going to fail sooner or later.

That’s why I don’t recommend charging an AC system at home. There are health hazards as well as hazards to the health of the system.

The best thing to do if you are having an empty system is to recharge it at a shop and learn how to find AC leaks in cars. That’s something that we are going to cover later.

2. AC Does Not Blow Cold Air

If your AC does not blow cold air it means two things. You either overcharged the AC, or you are having a lack of refrigerant and you need to learn how to find AC leaks in cars.

Both of these issues can ruin your air conditioning experience and disappoint you with the lack of cold air.

For the first reason if the AC is overcharged. The AC doesn’t work properly if it has too much refrigerant. If there is too much of it in the lines it’s going to prevent the refrigerant to convert from liquid to gas and opposite. This will mean that its work is not done and it doesn’t provide cool air.

If there is a lack of refrigerant on the other hand. You need to learn how to find AC leaks in cars. This will help you out a lot in order to solve this problem and we are going to cover that in the next chapter.

But when the AC doesn’t work well with a small amount of coolant is because it has not had enough of it to make an impact and cool the car down. If you are running your system with a fraction of refrigerant from what you really need. It will not going to cool your car down. That’s why you need to find AC leaks in cars in order to solve this problem.

3. The AC Loses Ability To Deliver Cool Air After Recent Recharge

If you recharged the AC recently and over time you are losing some of the cooling ability from your AC it means that the AC is leaking from somewhere.

These leaks are quite notorious and cause major headaches to car owners on a daily basis. In order to fix this problem, you have to learn how to find AC leaks in cars.

That’s why we are going to answer this question that bothers a lot of people after we explain how to charge the AC system.

How To Charge Your AC System?

Charging your AC system is a pretty straightforward business. You can do it both ways. Either you visit a shop or charge it by yourself.

Both ways work, but when you are deciding to charge your AC system you are putting your health at risk if you are not well equipped. If you get in touch with the refrigerant the most likely is that you are going to get frostbite.

Or if it splashes your face, it can burn your skin or damage your eyes. That’s why we are not recommending you to charge your system by yourself, and we would advise you to visit a shop.

Another thing is the risk of overfilling the AC system with refrigerant. These cheap kits that come do not include quality gauges. The gauges may even be fake and you will don’t know how much refrigerant you had put inside of your system.

Then the system will run poorly or will not even turn on. But supposing that you filled up the system as it should and it starts to lose refrigerant. You have to learn how to find AC leaks in cars. In order to fix the problem. And that’s what we are going to cover next.

How To Find AC Leaks In Cars?

There are basically three ways that you can use in order to find AC leaks in cars. And we are going to list them all in this chapter. It is good to note that AC leaks usually appear where there is a seal. They rarely appear on the lines, except if there was some damage to them caused by an accident.

  1. Use Soapy Water
  2. Ultraviolet Light
  3. AC Leak Detector

1. Soapy Water

The simplest method in how to find AC leaks in cars is using soapy water. Turn on your air AC to the max and apply some soapy water on the seals that you assume the leak comes from.

If there is a leak, bubbles should start to appear instantly. This is a good and simple method that you can try at home.

2. Ultraviolet Light

You can detect an AC leak by using UV light. All you need to do is to park your car in a dark garage and inspect all the lines and compressor with a UV light.

UV light is added to most refrigerant these days so you will probably not be required to add dye to the system.

A nice and thorough inspection will uncover all the secrets.

3. AC Leak Detectors

There are also plenty of leak detectors on the market that will tell you if your AC system is leaking or not. The downside of these detectors is that they are on the expensive side and I would not recommend them if you are not working with AC systems professionally. It’s much cheaper to go to a shop and do all the work there.

Cost To Repair The AC Leaks

The cost to repair an AC leak is not cheap. Especially if you do it at a shop. Mostly because the system has to be purged from all the gas that is inside and then after diagnosing the leak it has to be repaired.

This also depends on the parts that you are going to need. It may be a simple seal or some more expensive things. You never know. Then the system again has to be refilled with refrigerant.

In the end, this repair is probably going to cost you between $200 and $500.


In this article, we have covered a lot when it comes to how to find AC leaks in cars. We have learned the basics of every AC system and how does it work. Then we learned about the type of refrigerant that these systems are using and lastly, we have covered how to find AC leaks in cars.

Remember that there were three ways. The UV light method is the best. The soap and water method and the refrigerant leak detector.

If you are having some issues with your engine, you might like to check our articles on low oil pressure symptoms and bent connecting rod symptoms. Or if you have some transmission issues you might like to read how to check transmission fluid and metal shavings in transmission fluid.