- What Is a Refrigerant?
- Types of Refrigerants in Cars
- Why Is Refrigerant Recovery Important?
- How to Remove Refrigerant from Car AC
- Final Thoughts
Your car’s AC condenser sits right up front, which exposes it to rocks, bugs, and other debris.
A dirty condenser will most likely affect the performance of your car’s AC. You may experience lukewarm air from the vents, noticeable coolant leaks, and warning lights on the dashboard. With all these problems, you will probably want to replace the condenser.
Before you replace your condenser, however, you must remove all the refrigerant from the system. This guide will guide you on how to remove refrigerant from car AC.
Keep on reading to get to our step-by-step guidelines!
What Is a Refrigerant?
This is a mixture or substance that is used in the refrigeration cycle. It is a fluid that can be easily transformed from a liquid into a vapor and can also be condensed back into a liquid. And this needs to happen repeatedly without failure.
When compared to water, a refrigerant has very low boiling points. So, it needs very little heat to boil into a vapor, allowing it to extract heat more rapidly. The boiling point of water is 212 degrees Fahrenheit, but that of a refrigerant is -15.34 degrees Fahrenheit.
Types of Refrigerants in Cars
The air conditioning system in your vehicle is an advanced system that uses one of three types of refrigerants. The most popular refrigerant type in most vehicles is R134a.
Here’s an overview of all the three types of refrigerants used in car ACs:
Also known as Freon, this type of refrigerant was used in cars until 1995. It was the universal refrigerant for automotive AC. Freon was inexpensive and performed well because it cools to a liquid at nearly the freezing point of water, which means it was very effective at absorbing heat.
But the thing is, R12 contributed to the depletion of the ozone layer. As a result, the use of R12 in automotive air conditioning was banned. But vehicles that were produced before 1995 can still run R12 in their AC systems.
You are probably running R134a in your vehicle at this moment in time. It is the refrigerant that was selected to replace R12 or Freon for its low risk of flammability and effectiveness.
Unlike Freon, R134a is considered to be ozone-layer friendly. But the same cannot be said for the environment because it is packed with greenhouse gas. The gas does not break down quickly, contributing to the heating of the planet.
So, experts have come up with a better replacement for R134a called R1234yf refrigerant.
Vehicle manufacturers started using R1234yf in automotive air conditioning systems a few years ago in anticipation of the 2021 federal mandate to transition from R134a. The new refrigerant performs excellently and breaks down into harmless components in less than a quarter of an hour. It hardly causes any environmental impacts. The only major downside to this refrigerant is that it is flammable.
Why Is Refrigerant Recovery Important?
Did you know that a refrigerant is the lifeblood of your car’s air conditioning system? The compressor pumps the refrigerant through the AC system, hoses effectively carry the refrigerant through the AC system, while the condenser cools the refrigerant.
The evaporator, on the other hand, allows heat to leave. So, if any of these parts are affected, you will have to remove the refrigerant to be able to deal with the problem. That’s precisely why it is important to learn how to remove refrigerant from car AC.
Having said that, here are the main reasons why you would want to remove the refrigerant:
A Leak in the Refrigerant
A refrigerant leak can be catastrophic to an automotive air conditioning system. The cabin needs cooling, without which, it can be unbearable to drive under the hot sun.
So, a leak must be stopped and the refrigerant refilled. A refrigerant leak can be detected around the compressor, under your car, or inside the cabin. Immediate diagnosis of the leak and repair is required. You need to remove the refrigerant before you can seal any leak.
A Faulty or Bad AC Condenser
The main job of the condenser in your car’s air conditioning system is to transform the refrigerant from a gaseous state into a liquid. The liquid then continues to remove heat. If the condenser fails due to a leak or a clog, it won’t be able to remove heat.
If the condenser is damaged, you are going to get lukewarm air out of the vents. The condenser is made up of long metal integrated with metal fins. The integrated fins increase the cooling surface for superior heat dissipation.
Also, if the fins are damaged, the cooling fins will not function optimally. This usually leads to poor cooling performance and that’s why you get lukewarm air in the cabin and warning lights on the dashboard. Once again, you have to remove the refrigerant from the system before you can service the condenser.
How to Remove Refrigerant from Car AC
It isn’t hard to learn how to recover refrigerant from your car’s AC system. We will show you what to do in this chapter of our guide.
What You Will Need
These are the things you will need for this DIY project.
Manifold Gauge Set
A manifold gauge set is a basic tool for performing automotive air conditioning services. This tool is designed to access the refrigerant circuit as well as control refrigerant flow when removing or adding refrigerant.
A two-gauge manifold set is enough for most automotive AC systems. In a two-gauge set, one gauge is used on the low-pressure side (suction), and the other gauge on the high-pressure side (discharge). When the manifold set is connected to the AC system, pressure is regulated on both gauges at all times.
You need a recovery unit or machine to recover refrigerant from your car’s AC while the system is off. It has a pump and motor assembly and is capable of recovering refrigerant into a recovery tank without involving the AC compressor.
Recovery Tank & Vacuum Pump
A recovery tank is an important accessory in the removal of refrigerant. This reservoir is specifically made to recover hot coolant from the system. The pump is necessary for removing air from the recovery tank.
Step 1: Prepare the Recovery Tank
The very first thing you have to do is prepare your recovery tank. Typically, a recovery tank will be filled with nitrogen to protect it while in storage and shipping. Nitrogen, however, is safe to release in the air. So, you just need to open the valve and allow all the nitrogen to escape.
Once the nitrogen is completely out of the tank, pull a vacuum to get rid of moisture and air. To do this, you need a vacuum pump. But before you do that, you have to ensure that both valves on the tank are closed. Then, connect the vacuum pump to the blue side of the tank.
Turn on the vacuum pump and open the valve with a blue cap. Allow the pump to run for approximately 60 minutes. This will ensure that all the air has been removed from the tank.
After around one hour, close the valve on the recovery tank and turn off the vacuum pump. You must execute these steps in the recommended order to avoid sucking the pump’s oil into the tank.
Step 2: Connect the Manifold Gauge Set
You have to use a manifold set that is specifically made for your refrigerant type. The most common refrigerant in use is R134a. So, for the purpose of this illustration, we will be using a manifold set that is configured for the use of R134a.
Start by hooking up the set under the hood, using the integrated hook. Then take a look at the valves to ensure that they are in the correct position before you begin the setup. The valves on the gauge set must be closed (they close clockwise). Also, turn the valves on the hoses fully counterclockwise.
You need to know where your high and low-pressure ports are under the hood of your car. The low-pressure port is usually small in diameter and you can find it next to the alternator. It has a small cap that you have to remove (don’t lose the cap). Pull the collar backward on the low-pressure fitting, making sure the valve is closed, and connect it to the low-pressure port. Then, open the valve by turning it clockwise to bleed pressure into the gauge.
Next, locate the high-pressure port under the hood, which is normally located on the back. The high-pressure service port has a large diameter with a larger cap. Don’t lose the cap; that way, it’s easy to distinguish it from the low-pressure service port.
Grab the fitting of the high-side, push the collar backward, and connect it to the port. Turn the dial clockwise to open the valve and allow the refrigerant to go up to the gauge.
Step 3: Connect the Recovery Machine
Connect the yellow side of the manifold set to the connector labeled ‘IN’ on the recovery machine. Take the second yellow line and connect it from the port labeled ‘OUT’ on the recovery unit to the blue valve on the recovery tank.
Step 4: Start Removing the Refrigerant
Once you have successfully connected everything, it’s time to start removing the refrigerant from the AC system. Slowly open the blue liquid valve on your recovery tank and look out for leaks in the system.
Then open the blue liquid valve on the manifold gauge set. Next, open the outlet valve on the recovery tank and turn the machine on. Slowly open the inlet valve on the recovery machine until you hear a knocking sound. Then slowly close the inlet valve on the recovery unit until the sound stops.
Once the refrigerant has been removed from your car’s air conditioning system, the next thing you need to do is to open the red valve on your manifold set until evacuation is complete. We recommend that you let the red valve on until the gauges read zero, which may take approximately half an hour.
Once the manifold gauges reflect a zero reading, close the gauges valves red and blue. Next, close the inlet valve followed by the outlet valve on the recovery unit. Do this before you turn off the machine.
Now, you can close the blue valve on the recovery tank and start disconnecting the hoses. Don’t forget the caps for the low and high-pressure service ports. The small cap goes to the low-pressure service port, while the large cap goes to the high-pressure service port.
Can I recover refrigerant without a recovery unit?
You can remove refrigerant from the AC system of your car without a recovery unit. You will have to use the refrigeration system to pump all the liquid into a recovery tank.
What is the cost of a recovery machine?
Of the three special tools, you need for this DIY project, a recovery machine is the most expensive. You can secure one from approximately $300 to $8,000. But you can purchase the cheapest option for this project.
Is it expensive to have refrigerant recovered at a mechanic shop?
The cost usually varies from one mechanic shop to another. But you should expect to spend roughly $100 to $300.
Can I reuse recovered refrigerant?
Yes, you can reuse refrigerant that you have removed from your car’s AC. But any debris and oils must be removed from the refrigerant before reusing.
Also, read our guide on how to detect symptoms of low freon in the car.
As you have seen, removing the refrigerant from the AC system of your car isn’t a difficult proposition. Our step-by-step detailed guidelines with images will make sure of that. But here is the thing, this do-it-yourself project requires you to buy a few special tools.
These tools will cost you a few hundred dollars, of course. But, once you get them, you won’t have to go to a mechanic shop for refrigerant recovery. So, you get to save about $100 to $300 every time you have to remove the refrigerant from your car’s AC.