R-134a Auto Air Conditioning Refrigerant

It’s best just to stick with refrigerant without any additives. Harbor freight I think this was $5.99 in this link
12 Oz. R134a Refrigerant

Walmart had it for a dollar cheaper but was out of stock for online ordering. Be careful when using the small cans sometimes a small mistake can cost you a compressor sometimes it works and the person is happy. Usually I am a strong advocate to talk people out from using the little cans but somebody’s gonna do with somebody’s gonna do if they want to save money so long as you know what the gambling risks are. You could visit my photo album here on Prius chat I have some pictures and descriptions of tools some broken parts talk about oil additives.

You could research some Prius a/c related videos on my YouTube channel ( t lech) my channel name. In the search bar put in the term ( t lech Prius ) and a dozen of my Prius air conditioning videos will pop up

 

There is only one Type of R134a refrigerant. Any special packaging pictures or brand names are nothing more than advertising. There’s only three major refrigerant manufacturers in the United States that produce it and they repackage it Relabel it re-canned it with whoever’s name will pay to have it put on the label of the can. As long as it’s only pure refrigerant with no special additives it’s good to go for all vehicles including hybrids. Just make sure it has no leak sealant no special cooling additives no oil’s. You have to be careful sometimes in advertisement they showed a picture of one item but ship you something else. But as long as it’s pure R134A That is the only thing That matters

 

How do you know? Because they claim to meet AHRI 700 and SAE 2776 standard?

 

In this thread, post nr. 12, our colleague Mendel Leisk has found in the repair manual that oil IS needed...

It does not contain oil, according to this

4) Miscibility of R134a with oil: Oil is used as the lubricant in the compressor of the refrigeration and the air conditioning system. When refrigerant is sucked and discharged by the compressor, it picks up some oil particles. It is important that the refrigerant is miscible with the oil so that it can be easily separated from it. Refrigerant R12 is highly miscible with mineral oil, while R134a is miscible with the synthetic oil or lubricant. Thus when the refrigeration equipment is being altered for the use of R134a instead of R12, all the mineral oil should be removed from the system and it should be replaced with ester based synthetic oil.

In attach you can find OEM types of refrigerant.

 

Yes, oil is needed in AC systems for lubrication. I believe PAG oil was used for belt driven mechanical compressors and non-conductive ND11 oil for electric motor compressors.

Everyone want to know if R134A cans contains PAG oil because they are afraid of damaging electric compressor. This worry probably comes from those easy to use recharge cans with pressure gauge and injector nozzle. I think these type of products use to say included lubricating oil (I think mostly PAG?) mixed along with R134A for mechanical AC pump systems. Not sure if these type of product still contain lubricating oil today.

I would guess today's R134A cans without pressure gauge/nozzle are probably all pure R134A without any lubricating oil. Its up to the user to inject the correct oil into the system along with filling proper amount of R134A. Furthermore, all equipment used (any nozzle, hose, gauge etc) must be previously used only with the same oil type for your system to avoid contamination (or decontaminated)

I've done this once on an 11 Prius and its quite tricky. For example, how do we know how much oil remains inside a repaired leak system. Its unclear vacuuming the system will actually remove all the oil. Spoke to an AC shop and they usually inject 2oz of oil into the system just to be certain. I guess the risk of having more oil than spec is better than less.

 

Maybe everyone needs to read this method for Measuring Oil Contained in Air-Conditioning Components...

 

Normally, first you evacuate all it's inside, and also o flush can be done...
Finally you insert new gas...

Note that A134A is a gases mixture, and if you have losses, you never know how much of the x gas or the y gas is lost...

 

You’re kind of correct on some of your initial thoughts about the PAG oil and mechanical compressors.
But I will let you know they are starting to use for the past couple years some manufactures are using POE oil in mechanical compressors not just high-voltage electric compressors.

Now getting to the topic of the vacuum pump for recovery of refrigerant removing all the oil is false.
The vacuum pump does not remove any oil.

When using the recovery part of the machine that sucks out the refrigerant before you perform a vacuum if done incorrectly can remove an ounce or 2 ounce or even more under special circumstances on certain vehicles.
When the refrigerant recovery procedure is done correctly sometimes Noyle is removed at all or somewhere between 5 to 15 mL of refrigerant oil is removed.

And the shop technician when looking at the oil recovery bottle that measures out in milliliters after performing the refrigerant recovery procedure he will read the level and then only inject back the same amount of oil that was removed.

When oil or die or some sort of special magic snake oil additive is added to R134. They usually like to market this addition and brag about how great their product is by indicating this clearly on the can.

Usually when they can has no marketing material bragging about it having a special lubricant or a super advanced synthetic additive that makes your car run cooler or a UV trace dye.

Then the can is usually pure R134A.

The brand the manufacture or the packaging company or any special label put on a can does not matter the chemical make up is always the same there is no deviation or alternative to R134a

There are several manufacturers who sell hybrid electric dielectric compressor oil POE And they specifically will market this because the oil Hass to be moisture free.
And good manufactures of moisture free POE oil will usually come in a metal can.

Actually yesterday I released some videos in previous chat over in the second GEN I believe under maintenance performing a refrigerant recovery and the vacuum procedure and a recharge procedure.

this is one out of video out of four or five videos on this vehicle as I can testing and diagnosing and recharging.

You can just click on the channel in the header and watched either three or four videos I have many videos on hybrid Prius with their problems and often hell shops are the ones responsible for causing damage to a customers car.
Watching one of these videos I show a second 2005 Prius next to this one that has a damaged compressor later on in another video

 

Performing a AC flush when using a solvent that is propelled by dry nitrogen hopefully not sharp compressed moisture latent air.

The flushing procedure cannot be performed through the expansion valve so you physically have to remove the expansion valve which is OK on the later model prices because it’s kind a easy to get to you up on the firewall in the engine compartment.

But the earlier model Prius had the expansion valve located under the dash connected to the evaporator will take 7 1/2 hours to get to.

The shop that says they add 2 ounces of oil to every vehicle they service is not a real mechanical shop they don’t know what the hell they’re doing I would definitely stay away from that shop when it comes to air-conditioning.

On the Prius you have a complete oil refrigerant charge of 2.7 ounces to 3.7 ounces so if you add another 2 ounces on top of that by what percent are you over oiled ?

Like your engine oil do you have 3.7 quarts of oil in your engine how about if I just routinely every time you come into my shop I added an extra 2 quarts of oil on top of that 3.7 quarts of oil.
Same thing

 

I forgot to mention don’t pay too much attention to Toyotas factory manual on air conditioning recharge procedures or oil quantities.

It’s often just re-printed stuff from the 1970s that was re-edited and re-published by somebody who knew absolutely nothing about air-conditioning.

Some of the literature contradicts itself with the quantity of oil in the refrigerant system but then when you go to the paper that actually specifies the exact quantity of oil that is contained in every component when spread throughout the system and you do the math and added it up it’s completely different.

And as for trying to use the site glass bubble indicating method as written in when the Toyotas papers that scenario can change depending on the ambient condition your vehicle is located on that very day from day to day .

The weight of your refrigerant charge can actually be so low and the ambient conditions just perfect even when your refrigerant level is less than half full you can still have a perfectly clear sight glass having 42° air coming out of your dash in plenty of water condensating and dripping under the car out of the evaporator case just like a perfectly for operating refrigerant system.

As indicated in the video above that I attached a link to showing this very scenario that I come across quite often.

One of the reasons I refer to as technicians or people who fill the refrigerant by looking at bubbles in the sight glass I called them (Bubble Boys)

 

I bought my 07 new and its been running good has new hybrid battery but over the 14 years the ac has started to not cool so well. Now it only cools if the car is in the garage the second you go outside and start driving it has cold air coming out but not very good.

With the ac on max cool on recirculate in the sight glass it looks like liquid stream moving very fast through it I guess this is a bubble stream.
If so very tiny bubbles flowing very fast. Looks like water flowing through it.

When car off the sight glass is empty and has very shiny aluminum with clear glass.

I have owned a freon detector for a few years says its 134 capable but it does not detect anything. Just slow tick.

This one:

The front condenser looks brand new I clean it often. I also service the dash ecoil with cleaner like Kool It.I have not done that in about 2 years though. We don't smoke & new cabin filter.

Compressor is quiet when ac is on. Going to take it in. Never had any ac work done and I don't use the the auto parts store bottles. Those never worked for me.

 

That refrigerant leak detector is notorious sometimes for detecting leaks from other things like gases for expanding foam windshield washer fluid brake fluid your under arm your coffee.
The cheap leak detectors when they’re new in good condition will find big leaks like if you cracked open the bottle and made a squirt of refrigerant come out and then put your leak detector down to it it finds that usually.

when the refrigerant runs that low the compressor really has a spin up at high RPMs in a attempt to move more refrigerant trying to make it self cold.

When you put your hand on the large suction line pipe entering going back to the compressor you find out that it’s warm no longer frigid cold at that point is when the compressor is starving for coolant to come back to it to cool off the electric windings in the motor

 

so let’s say this repair shop can you check to extra ounces of oil into a Prius and a total system capacity is 3.5 ounces
So how many percent overcharge by adding two additional ounces to that system is it ? More is better ??? Then much more must be much better

you should ask that same shop do they put a couple extra ounces of refrigerant in the system so they can compensate for a system with a leak so the system will last longer .
Because we know more is better so a few more ounces of refrigerant in a Prius air conditioning must be really good. . I like shops like this they make me a lot of work.

 

In this video in the background you can hear the sound of the compressor attempting to perform cooling in the cabin area by over winding the compressor motor to 5000+ RPMs.

in one of the later videos when I do the refrigerant recovery I find out I believe it was 330 g was in the system which is only a little low and should’ve performed some decent cooling on a mild temperature day but was actually not working and barely flowing refrigerant as you can see in the sight glass.
There was a few more videos in the series on this 2007 Prius

In the next video I take the temperature of the discharge temperature of the refrigerant coming out of the compressor and the temperature of the case of the compressor it’s literally so hot it would boil water hotter than 212°

And when I recover the refrigerant out of the Prius as I removed one of my hoses a little bit of gas escaping had an extremely strong smell like Pine-Sol or turpentine

Which I know some of the AC flush solvents smell like I’m very familiar with the smell especially if somebody tries to flush through an expansion valve which you cannot but you try and the solvent gets trapped inside the evaporator as a liquid you cannot remove it when it over Dilutes the oil and damages the compressor

And you cannot use the flushing solvent through a already damaged compressor that has put debris into a micro channel condenser the condenser cannot be flushed it must be replaced.

If you attempt to use the turpentine hydrocarbon based AC flush on a micro channel condenser that has a receiver dryer like the Prius have.
The flashing solvent will also get trapped inside the receiver dryer and the desiccant sock will act like a sponge absorbing the turpentine-based solvent flush contaminating your system.

Which I realized immediately when I opened up one of the hoses and I got that strong smell of AC solvent flush based on this chemical compound.

It’s good when you use it on individual components like hoses and lines.

It’s good when you use it on old fashion large tube and fin condensers

it’s good to remove only burnt oil with no metallic or any type of physical particles contamination in a condenser like micro channel but you must remove the desiccant sock out of the condenser.

it’s OK to use in a micro channel evaporator without the expansion valve while it’s out on a bench top being flushed through one component at a time only.
Never trying to flush it through a expansion valve attached to a evaporator under the dash

 

OK folks. I've been researching this issue for days. Someone on the forum hit the nail on the head. Let me summarize what I have learned for those seeking an R134a refrigerant for a Prius.
1) We need an R134a refrigerant that uses or is compatible with Polyolester (POE) oil. The ND OIL 11, such as that manufactured by ENEOS Corporation, is the answer, according to Denso, a Toyota affiliate.
2) 99+% of the R134a we see marketed is based on being compatible with Polyalkylene Glycol (PAG) oil and contains a caution that says, "Not for Hybrid vehicles with electrical driven compressors.” I suspect that the cans which do not have this statement, are still of the PAG variety and therefore should not be used in a Prius. I also suspect that many Prius owners have unsuspectedly failed to read the cautions on the refrigerant and used them without knowing the harm they were doing to their cars.
3) A/C Pro makes a refrigerant called NR-134AV, A/C Pro Extreme kit -ACP-210AD, HYB-134a. Note that it appears to be made for hybrid vehicles. But emails from them confirm that it is not to be used for hybrid vehicles like the Prius with electrical driven compressors. A/C Pro recommends that we find a straight R134a without oil of any type. This brings up another question.
4) When straight refrigerant (if found) is added to an underperforming air conditioning system, a precise amount of the recommended oil should be replaced. This oil must be added to the high side, not the low side. Obtaining this ND OIL 11 is an issue as well as knowing how much oil to add to the system, obtaining the HIGH/LOW charging cables, and properly learning how to do the job oneself. In short, it may be outside the scope of most do-it-yourselfers.
I've been in contact with NAPA, Advance Auto Parts, O’Reilly’s Auto Parts, Auto Zone, A/C Pro, Amazon, and Denso.
Lastly, . . . .
5) Give up, buy, and use the R134a (PAG) that is on the store shelves. From what I have read, this is a very bad solution. It has to do with the electrical requirements of the Hybrid Synergy Drive and how that air conditioner compressor requires a totally unique lubricant. Even a small amount of PAG will cause a complete failure of the compressor and will cost hundreds of dollars to repair.
Most auto repair shops and some Toyota dealerships may not be giving Prius owners the service they think they are! Your thoughts?