R1234YF Refrigerant

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Tom991

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My 2020 expedition came with R1234YF refrigerant in the AC. Recently I had to take the car to the shop since the AC suddenly began blowing warm air. Turns out the somehow the R1234YF was very low. They flushed the system and refilled it with 134A refrigerant and a dye. The mechanic told me to drive it for a weak and bring it back and they'll find the leak. I asked about the 134A refrigerant being compatible with the system. He told me that it was and that the R1234YF corrosive and could shorten the life of the AC system. Who's idea was it to go to a refrigerant that wasn't good for the system? Was it an EPA mandate or did the manufactures decided to use something that would shorten the life of the AC system to make money on repairs. My Expedition only has 50K miles on it. AC systems on all my other cars lasted well beyond 100K miles before needing repair.

Any ideas?
 

99WhiteC5Coupe

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My 2020 expedition came with R1234YF refrigerant in the AC. Recently I had to take the car to the shop since the AC suddenly began blowing warm air. Turns out the somehow the R1234YF was very low. They flushed the system and refilled it with 134A refrigerant and a dye. The mechanic told me to drive it for a weak and bring it back and they'll find the leak. I asked about the 134A refrigerant being compatible with the system. He told me that it was and that the R1234YF corrosive and could shorten the life of the AC system. Who's idea was it to go to a refrigerant that wasn't good for the system? Was it an EPA mandate or did the manufactures decided to use something that would shorten the life of the AC system to make money on repairs. My Expedition only has 50K miles on it. AC systems on all my other cars lasted well beyond 100K miles before needing repair.

Any ideas?


Your mechanic should not have filled the system with a different refrigerant than is specified by the manufacturer.

I can’t answer you questions.
 
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Tom991

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This is a reputable shop. The AC tech that works there all he does is work on AC systems. He is school trained in automotive AC and has all the credentials. Told me that the AC system is designed to use either 134A or R1234YF. I'm just trying to get to the bottom of why the new refrigerant when the old one works as well as, costs less, and is not corrosive and the system will last longer using 134A. It's a no brainer if you ask me.
 

Hamfisted

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I would be shocked if a certified mechanic used 134a in a 1234yf system. Maybe you misunderstood him ? The two gases require different expansion valves and have different pressures and boiling points, and can damage system components.
 
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Tom991

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I found this article on the differences. It appears to be all EPA driven.

It won't let me put the link in but basically it states.

As of January 1, 2021, the United States Environmental Protection Agency mandated that all passenger cars and light-duty trucks coming off the assembly lines must utilize R-1234yf as their HVAC system refrigerant. The European Union forced this changeover on January 1 of the previous year.

While R-1234yf could be the perfect replacement for R-134a, there is one major challenge with this new technology. The R-1234yf is much more reactive than R-134a. On the positive side, this higher reactivity is why R-1234yf is so much more friendly to the environment. It tends to react with other gases in the atmosphere and break down within a couple of weeks, as compared to R-134a, which remains stable for over a decade. The problem with a highly reactive refrigerant is that it can also be aggressive toward the lubricants used in the HVAC system. This leads to oil degradation which causes excessive wear and eventually compressor failure.
 
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bb37

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Here's a link to the Wikipedia article for 2,3,3,3-Tetrafluoropropene which is the chemical name for R-1234yf. Yes, the change to R-1234yf seems to be driven by global warming concerns, particularly in Europe. GM started using it in 2010. As of 2022, its estimated that 90% of new vehicles in the US came with R-1234yf. Honeywell, who produces R-1234yf, claims that it's a drop-in replacement for R-134.

 
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Tom991

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My 2020 expedition came with R1234YF refrigerant in the AC. Recently I had to take the car to the shop since the AC suddenly began blowing warm air. Turns out the somehow the R1234YF was very low. They flushed the system and refilled it with 134A refrigerant and a dye. The mechanic told me to drive it for a weak and bring it back and they'll find the leak. I asked about the 134A refrigerant being compatible with the system. He told me that it was and that the R1234YF corrosive and could shorten the life of the AC system. Who's idea was it to go to a refrigerant that wasn't good for the system? Was it an EPA mandate or did the manufactures decided to use something that would shorten the life of the AC system to make money on repairs. My Expedition only has 50K miles on it. AC systems on all my other cars lasted well beyond 100K miles before needing repair.

Any ideas?
I would be shocked if a certified mechanic used 134a in a 1234yf system. Maybe you misunderstood him ? The two gases require different expansion valves and have different pressures and boiling points, and can damage system components. Don't run the AC till you get the 1234yf back in there. There was no reason to put 134a in there.
The articles I read disprove that 134A can't be used successfully in a 1234yf system as long as the compatible oil is used as well. The AC runs fine with the 134A in it. There is an aftermarket 1234yf that is more AC system friendly that's fully compatible with the system. I have it documented on the receipt that 134A was installed in the system and the AC techs guarantee in front of witnesses that it won't damage the system. Since 1234yf can directly replace 134A according to the article that BB37 posted it seams like any full replacements of refrigerants and the correct lubricant won't negatively effect how the system operates. Right now it's running super cold. In a week I take it back to check for leaks that they didn't find with their sniffer equipment. Then they'll do what they have to do to include using the more AC friendly aftermarket product
 
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Tom991

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Here's a link to the Wikipedia article for 2,3,3,3-Tetrafluoropropene which is the chemical name for R-1234yf. Yes, the change to R-1234yf seems to be driven by global warming concerns, particularly in Europe. GM started using it in 2010. As of 2022, its estimated that 90% of new vehicles in the US came with R-1234yf. Honeywell, who produces R-1234yf, claims that it's a drop-in replacement for R-134.

I kind of figured this was EPA driven along with the unintended consequences that went along with it.
 

OpticonBill

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As a EPA 608 certified HVAC guy, there are some serious problems with this thread. Not the least of which, it is a violation of the Clear Air Act to "tamper" with the original design of the vehicle system. A vehicle designed to use R1234YF refrigerant also has devices to prevent the use of alternative refrigerant such as R123a. The use of adapters to bypass the devices on a R1234YF system in order to introduce a different refrigerant such as R123a is counted as a second violation. If I remember correctly, I think the current fine for "Tampering" is around $44,000 and the fine for bypassing the device is another $4500.

Should R123A refrigerant be used to replace R1234YF refrigerant there will likely be further problems down the road should the system need servicing. The service person will not know that the system labeled R1234YF has R123a refrigerant and could unknowingly cross contaminate a R1234YF recovery container with R123a which will render the refrigerant in the bottle unusable. He will likely need to pay a refrigerant recycler to dispose of it.

I haven't even got into the issues that arise when using a refrigerant in a system not designed for it. Only a hack AC guy will claim the two are compatible, they are not. The hack AC guy is only saying that because the R123a is cheaper or for one reason or another he can't obtain the R1234YF refrigerant.
 
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Tom991

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Well seeing that the law didn't go into effect until September 2021 and my expedition is a 2020 the law doesn't apply to my car. The shop is EPA certified and the certificates are on the wall. Did you know that R134A has 25% greater cooling capacity than R1234YF. Also the certification deals with being certified on the equipment to safely evacuate and dispose of or recycle the refrigerant either R134A or the new stuff that is more corrosive and doesn't cool as well. I've discussed all this to him and he sent my a link to the EPA's requirements.

There is absolutely no differences between the physical AC unit that came with one over the other refrigerant. Maybe the valve, as it was with the R12 to R134A systems. I'm not sure. I do know I had an old car running R12 years ago. When 134 came out they were selling conversion kits in the auto parts stores. It was a really simple change over. Get a shop to evacuate the R12, replace the dryer and put on new valve adapters that came with the kit, connect the guages, which I borrowed, put the lubricant in and then put the specified amount of R134 in, both of which came with the kit. It worked my AC blew cold.
 

Avian

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This is a reputable shop. The AC tech that works there all he does is work on AC systems. He is school trained in automotive AC and has all the credentials. Told me that the AC system is designed to use either 134A or R1234YF. I'm just trying to get to the bottom of why the new refrigerant when the old one works as well as, costs less, and is not corrosive and the system will last longer using 134A. It's a no brainer if you ask me.
I had a Medically Licensed Doctor nearly kill me years ago (AKA "Quack")

The condensers are RADICALLY different between the 2 refrigerants. Finding leaks is made easier by pressurizing the system with CO2 gas, and using a special leak finder (I have this equipment in my shop), and a good bubble making soap.

It AIN'T rocket science. I'd be very upset if he did that to my vehicle.
 
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