Are you running an old AC system and you are looking to make an R12 to R134a conversion? Getting your car up to spec can be an expensive thing since modern cars are not using this old refrigerant. But we are going to help you out with that and teach you how you can do it and how much it is going to cost you.
Having a properly working AC system in your car is key. You just don’t want to drive on those hot summer days with your windows cracked open. They provide some cold air to enter the car but not something significant that will make you feel comfortable and not lose focus.
And that is the most important thing when running an AC, keeping the focus is key if you don’t want to get into an accident during the hot summer days. Especially if you live down south where temperatures get boiling hot during these days. And if you run a classic, sadly you cannot use a modern refrigerant. That’s why some work has to be done to your car. And we are going to help you out to learn what you really need.
First, we are going to cover the basics of these AC systems and learn how do they work. Then we will learn more about what types of refrigerant are these systems using and we will cover the R12 and the R134a. After, we will discuss retrofitting your old system for R134a use and the costs involved in this process. Lastly, we will discuss some common questions concerning AC systems. So, if you want to learn more about R12 to R134a conversion, follow along.
What Is An AC System?
An AC system or an air conditioning system is a system designed to maintain the temperature inside of the vehicle’s cabin at a certain level.
The idea of an AC system in cars is old as the car itself. But it was in 1933 when the first kind of these systems was patented and offered in automobiles. In the beginning, this system was only offered in high-end luxury vehicles.
But somewhere in the ’50s and ’60s, these AC systems saw a big demand. Lincolns and Cadillacs were the first cars that got this luxury item that did wonders and made driving an enjoyable experience in the hot summer months. Back in the day, not everyone could afford one of these systems.
But soon, cars evolved and so did the AC systems. In-car air conditioning has hugely improved and was delivering a good performance for less money. But they were still kept as an option until recently when most car manufacturers started to include the AC systems as standard in most of their lineup.
Nowadays there is a low chance that you are going to see a car that doesn’t have an AC system. But not all of us are driving new cars, some of us are driving cars made even before 1994.
So, if you have an older car, you should consider doing an R12 to R134a conversion because this old refrigerant isn’t produced anymore. But more on that, we are going to cover a bit later after we discuss some topics and learn how these systems work and why recharging is essential.
How The AC System Works?
Have you wondered how this AC system works? What kind of magic is happening inside of the system to deliver you cool air? Well, in this chapter, we are going to cover precisely that and teach you how this system works step by step.
The first thing you need to know is that the AC system is a circulating system that is circulating the Freon also known as a refrigerant and makes your car cool.
The core of the AC system is the compressor. This compressor is compressing the refrigerant and turns it into a gas. Then this gas is pushed into the front condenser of the vehicle where this hot gas is cooled from the fan that is blowing in front of the car. And here the magic happens. This high-pressure gas that is pushed from the compressor is liquefied in the condenser.
Then from the condenser, this liquid gas is pushed to the dryer. The dryer is a component that it capturing the moisture that is in the liquid gas and from there the high-pressure liquid gas is pushed into the expansion valve. In this expansion valve, this refrigerant is converted from high-pressure gas into a low-pressure liquid.
Soon after it is converted, the refrigerant is pushed into the evaporator where it is again converted into low-pressure gas form and then again pushed in the compressor to make another circulation. But where does the magic happen?
The magic happens in the evaporator, the evaporator is something similar to a condenser. There is a blower motor installed that is blowing in the evaporator and thus, blowing cold air into the cabin. But what about the R12 to R134a conversion? More on that in a bit.
Types Of Refrigerants Used In AC Systems
Now let’s discuss the types of refrigerants. This will be of great use for you if you want to retrofit your system and make an R12 to R134a conversion. Knowing the types will help you learn what you really going to need to pull this off.
In the following chapters, we are going to cover these two types of refrigerants, and later in the article, we will discuss the R12 to R134a conversion and if this is possible or not. So, let’s begin.
What Is R12?
R12 also known as Freon was patented by Thomas Midgley Jr. back in 1928 and then this refrigerant solution was something groundbreaking and something that changed the world.
This was because it did its job very well and was non-flammable and also non-toxic. How better can it be? The R12 dominated the world right until the 1980s when it was proven that this gas is making damage to the ozone layer.
At this point, the R12 was slowly starting to be phased out and now it’s completely replaced by the R134a.
Nevertheless, there are still a ton of vehicles that use R12 and whose owners are looking for R12 to R134a conversion. But more on that we will cover in a bit after we cover the R134a as well.
What is important though, is that the R12 was a product of DuPont and was branded as Freon. So, if you are looking online for a refrigerant and you see the name Freon then for sure this is an R12. Still, it’s extremely less likely that you will find Freon on the shelves. Now let’s focus on the R134a.
What Is R134A?
The R134a was the replacement that was introduced on the market for the R12. This is the official replacement for the R12 since 1987 and is heavily prohibited to use R12 since these measures were taken to protect the ozone layer of our planet.
And the R134a is a really good replacement for the R12. Similar to the R12 it is a non-toxic and also a non-flammable gas that doesn’t damage the environment.
The R134a is the most widely refrigerant used right now on cars and if you have a modern vehicle that was produced since 1994 it is highly likely that is already using R134a refrigerant.
That’s why you need to check what type of refrigerant your car is using. If it uses an R12, you will definitely need to do some retrofitting and plumbing to accommodate the use of this new gas. This is something that is known as R12 to R134a conversion. But more on that later, now let’s see what will happen if you put an R134a gas in an R12 AC system.
What Can Happen If You Put R134a instead of R12?
You shouldn’t mix these two types of refrigerants by any means. They are two different chemical compounds. So, they cannot be mixed interchangeably. Although they are refrigerants, they don’t love to work very well when mixed.
You might face a ton of issues and also damage your system. The R12 systems work differently than the R134a AC systems. If you put R134a gas in an R12 system, the first thing you will notice is the leaks that will develop and damage your system. Your AC compressor can develop leaks and can be damaged. This could be a total nightmare to fix.
In addition to this is the different oil that these two systems are using. One of them, the R12 is using mineral oil. This oil is completely incompatible with the oil used on the R134a. If the R134a comes in contact with the mineral oil it could prevent the oil from returning to the compressor. This could be damaging for the compressor since the heat will not be disbursed outside and the compressor could overheat.
If the compressor fails, then you can expect to pay a hefty fee to bring it back to normal. Sometimes the only solution would be to purchase a new compressor compatible with R134a. But more on that we will cover later when we will discuss the R12 to R132a conversion.
Why Would You Want To Do A R12 To R134a Conversion?
But why would someone want to do an R12 to R134a conversion? The reason is simple, the system is empty of refrigerant and you need to add refrigerant. But R12 is not available on the shelves. So, the only way is to retrofit your system to use the R134a refrigerant.
And even if your system is working fine, you should still remove the R12 refrigerant because it is damaging to the ozone layer. We all want to save the planet but we need to take some action and do something good and beneficial.
So, if you have a classic car that is running its old factory AC unit, maybe it is time to retrofit it and give it a new life. Drain the R12 which is damaging and retrofit your system with the R12 to R134a conversion that we are going to discuss later in the article where we will learn what are the key components that are included in these kits and how this procedure is performed.
Can I Still Find R12 Freon Refrigerant?
Unfortunately, finding an R12 refrigerant is close to impossible. This product has been banned off the shelves for about 30 years and you will not come across it again. Except for some unsold cans that were left for decades in some storage facility.
Either way, you don’t need the R12. As we said, it is damaging for the environment as well as not available anywhere. Your only focus in this situation should be an R12 to R134a conversion to your AC unit.
Doing a proper conversion is key if you want to bring back your AC system to modern spec and make sure that it runs on the newest type of refrigerant which is the R134a. But what are the components involved in retrofitting an existing R12 system? Let’s find out in the following chapters where we will cover this topic in detail.
Components Involved In Retrofitting An R12 AC Compressor
Before we start discussing how you can do an R12 to R134a conversion. Let’s first take a look at the components that will be required for this job. Primarily you will need a conversion kit for your specific AC unit. You need to find a specific unit since not all AC systems on each car are the same.
In this kit are included many components. Namely, for this job, you will need an AC flushing kit to flush the old R12 refrigerant from the system. The next thing you will need is the HNBR O-ring kit for your vehicle. In addition to this kit, you will also need an R134a retrofit kit with a port adapter, port caps, oil, as well as a retrofit label. Also, you will need an R134a pressure switch and orifice tube.
In addition to all these components, you will also need a specific R134a dryer for the vehicles that are produced before 1991 and don’t come with a dryer.
It is also worth mentioning that if you are running a weaker AC compressor, you will also have to replace the compressor as well. Since these compressors are not able to withstand the load with running the new R134a refrigerant. The most concerning AC compressors are the Harrison DA6 and the Ford FX-15. Replacing them with more modern units will make your R12 to R134a conversion a breeze.
But how you can perform this conversion? It is doable to perform all of this work at home? Well, yes it is and in the following chapter, we are going to explain to you how you can do this work at home with common tools and the parts that we listed above if you want to make the conversion to be perfect.
How To Do A R12 To R134a Conversion DIY?
Now let’s cover something really cool and that is how to convert your system to run the R134a refrigerant. To be honest, nobody wants to pay hundreds of dollars to mechanics for a simple task like refilling the refrigerant or retrofitting your car to work on the R134a refrigerant. Also known as R12 to R134a conversion that is the main topic of this article.
Why pay a ton of money when you can do this work, all by yourself at home with common tools. But before you start this process, make sure that you get all of the pieces that are required for this retro fitment. There are specific kits for each car with a manual that will tell you everything you need to know when it comes to this process.
But you shouldn’t worry because we also going to explain to you how this work is done just to place things into perspective and you to have a better idea of what to expect from this task and if you can do it or not. Either way, it will be a pleasure for me to guide you through the steps. Remember that we are covering the professional method and how this thing would be performed at a dealership. So, let’s begin.
Step 1
The first step will require removing the remaining R12. Remember that you don’t know how much R12 the system has, so flushing the system to make sure that nothing is inside is your number one priority. Releasing this gas into the atmosphere could be damaging for your health as well as for the environment. You don’t want that. Get a flush kit and properly dispose of the R12.
Step 2
The next step will require flushing the evaporator as well as the condenser from the mineral oil. Old systems use mineral oil while modern systems use synthetic oil. This oil cannot be mixed. Along with the evaporator and condenser, the high pressure, as well as the suction lines, have to be also free from any mineral oil. After you release all the mineral oil, refill with the specified amount of PAG or Ester in the system.
Step 3 – R12 To R134a Conversion
Step 3 will require swapping some components with new ones. These are the drier or accumulator, high and low-pressure switches, and the orifice tube. Also if the car is produced before 1991, replace the hoses as well. In addition to this, you need to replace all the O rings and replace them with the HNBR O-rings.
Step 4
After you did replacement on all these components, the next step is to attach a vacuum pump as well as a manifold gauge that was set to pull the vacuum for about 45 minutes (this isn’t necessary if you are doing it at home. But still is desired to make sure that you don’t see any leaks down the road). After testing, check for possible leaks if there are none, you are good to go.
Step 5
Step 5 requires connecting the high and low port adapters and recharging the air conditioning system with R134a refrigerant. After doing the final step, make sure that everything works well and you are good to go. That’s how R12 to R134a conversion is done professionally.
What Is The Right Amount Of R134a For Your System?
It is important to note that the amount that you need to add to the new R134a is less than you would usually add if you were using an R12 refrigerant. For this, you need to look at the real numbers for your specific vehicle.
But to turn things into perspective, we will make a comparison. So if you needed to add 1.5 pounds of R12, with the R134a you will need to add 1.1 pounds. So, you get my point. Learn the real numbers of R134a for your car and make sure that you don’t overfill your system. Because if you do the R12 to R134a conversion would be in vain since the system will not work properly.
Cost To Do A R12 To R134A Conversion
The cost for this R12 to R134a conversion depends on whether you do it by yourself if you go to a mechanic or you go to a dealer.
If you decide to do the R12 to R134a conversion by yourself, you can expect to pay the least money. About $100 to $150 for the parts and the refrigerant itself.
If you decide to go to a mechanic, you will also not spend a lot of money to get this work and it will cost you somewhere between $200 and $300.
On the other hand, if you decide to do this at the dealership, you might be quoted to pay a hefty price. About $550 to be more exact. That’s why you should try to find the cheapest way for this R12 to R134a conversion.
AC Retrofitting: How to Convert Your Car’s R12 AC System to R134a – Facts
- If your car was manufactured before 1994, its air conditioning system may still use R12, a refrigerant deemed harmful to the environment that must be replaced with R134a.
- R134a is lighter than R12, so to charge the system correctly, you must fill it with between 75-85% of the factory-set capacity for optimal cooling.
- Before retrofitting the system from R12 to R134a, you need to remove the R12 refrigerant, which should be done by a licensed professional who can dispose of it properly.
- To retrofit your R12 system, you must add new fittings to the low and high side service ports, put a retrofit label on the connectors, and hook up gauges to vacuum down the system for at least an hour.
- After hooking up the gauges, connect the yellow hose to the R134a can and add the refrigerant until you reach the appropriate capacity, which is less than what was needed with R12.
- If you retrofit your R12 system without replacing necessary parts, such as O-rings, it may be illegal where you live.
- If you’re thinking of getting an R134a system installed, the cost can be around $2,000 to $4,000, while a professional retrofit may cost around $250.
- R134a may not cool as well as R12, but it’s much more tolerant against under and overcharging.
- Specific conversion kits containing the necessary parts for the conversion are available for many car models, while pressure switches may also need to be replaced in some models.
- R12 was phased out and replaced with R134a due to environmental concerns. Mixing R134a with R12 or vice versa can lead to costly system failures and should never be done.
Conclusion To R12 To R134a Conversion
In this article, we have covered quite a lot when it comes to the R12 to R134a conversion. First, we learned what the AC system is and how it works.
Then we covered the types of refrigerants. Precisely, the R12 and R134a. We learned why the conversion is necessary and why the R12 isn’t produced anymore.
Then we covered the components that you will need to replace and after we saw how you can do this work at home using common tools and a retrofit kit. Lastly, we discussed the price and to be honest it is not that expensive. It will cost you about $250 to get this work done professionally.
