Yellow charge hose questions

[acnoob]

Hello
I need to fix an ac issue on my car that has r1234yf

I bought this manifold guage set:
(Moderator removed link.)

question 1)
I notice these r1234yf does not have a purging valve on the yellow charging hose...is this going to be a problem when charging?

question 2)
are all r1234yf yellow charge hose left hand thread on the can side?

question 3)
are all r1234yf yellow charge hose a 1/2 female fitting on the can side?

[tbirdtbird]

OK, first, no links to auction sites are permitted here, please remove.
Tim, the site owner, and proprietor of ACkits.com, has excellent quality products at excellent prices. You missed an opportunity to get quality equipment.

Second, we do not do 1234yf in this shop, so we'll need to wait for JohnHere or someone else to come along. AFAIK all the 1234 stuff is L hand thread

[Cusser]

I need to fix an ac issue on my car that has r1234yf

I feel for you !!! Remember, we were all "promised" that R134a was safe and the answer to all auto AC woes !!!!

question 1)
I notice these r1234yf does not have a purging valve on the yellow charging hose...is this going to be a problem when charging?

Why can't you just unscrew the hose fitting slightly/briefly at the manifold end to purge out air???? Like I did with R134a earlier in the week....

[JohnHere]

question 1)
I notice these r1234yf does not have a purging valve on the yellow charging hose...is this going to be a problem when charging?

Why can't you just unscrew the hose fitting slightly/briefly at the manifold end to purge out air???? Like I did with R134a earlier in the week....

OP, it's not a problem at all. In fact, I had the same concern when I started to deal with R-1234yf a few years ago.

My Manifold Gauge Set (MGS) is configured essentially the same as yours, with all three hoses permanently attached into what appear to be 1/8" NPT threads in the MGS. Like yours, my hoses don't have the typical knurled thumb-screw fittings on the MGS ends that we're accustomed to seeing. Therefore, the yellow hose can't be partially unscrewed at the MGS to allow for purging the hose.

However, I soon discovered that my yellow hose has a check-valve in the end that attaches to the vacuum pump and/or the refrigerant source. Look closely at your yellow hose end (the end with the knurled thumb-screw), and I'm sure you'll find a check-valve in there as well.

The check-valve makes it unnecessary to purge the yellow hose with refrigerant (and waste some costly R-1234yf) as we've traditionally done with R-134a MGS's not having a check-valve in the yellow hose. All the hoses in these particular R-1234yf MGS's—including the yellow hose—will be evacuated of air and moisture along with the MGS itself and, of course, the A/C system. This presumes that you're not going to attempt "topping up" the system, which professional MVAC techs ardently discourage—and for good reasons.

On removing the yellow hose from the vacuum pump and subsequently connecting it to a refrigerant source, no vacuum will be lost and no air and moisture will enter the hose because the check-valve will prevent that from happening. So don't worry—there's no need to purge the yellow hose with this type of R-1234yf MGS.

question 2)
are all r1234yf yellow charge hose left hand thread on the can side?

Yes. They're all left-hand 1/2" ACME threads, including the can "tapper" valve if you use one.

question 3)
are all r1234yf yellow charge hose a 1/2 female fitting on the can side?

Yes. Those, too, are left-hand 1/2" ACME threads. This is done to prevent inadvertently connecting R-1234yf hardware to R-134a hardware and mixing the refrigerants.

[Cusser]

Always good stuff to learn on this site. Like avoiding vehicles with 1234yf !!!

[JohnHere]

I definitely hear you. The cost of R-1234yf alone will cause people to shy away.

[tbirdtbird]

Once some of our racer friends learned that Miles and I were not going to service 1234yf cars, they actually sold their daily drivers and got used cars that were still 134a.

Have no fear, in a couple of years the EPA will ban 1234yf and come out with another refrigerant....they like to play with the numbers in Campbell's alphabet soup

[acnoob]

question 1)
I notice these r1234yf does not have a purging valve on the yellow charging hose...is this going to be a problem when charging?

Why can't you just unscrew the hose fitting slightly/briefly at the manifold end to purge out air???? Like I did with R134a earlier in the week....

OP, it's not a problem at all. In fact, I had the same concern when I started to deal with R-1234yf a few years ago.

My Manifold Gauge Set (MGS) is configured essentially the same as yours, with all three hoses permanently attached into what appear to be 1/8" NPT threads in the MGS. Like yours, my hoses don't have the typical knurled thumb-screw fittings on the MGS ends that we're accustomed to seeing. Therefore, the yellow hose can't be partially unscrewed at the MGS to allow for purging the hose.

However, I soon discovered that my yellow hose has a check-valve in the end that attaches to the vacuum pump and/or the refrigerant source. Look closely at your yellow hose end (the end with the knurled thumb-screw), and I'm sure you'll find a check-valve in there as well.

The check-valve makes it unnecessary to purge the yellow hose with refrigerant (and waste some costly R-1234yf) as we've traditionally done with R-134a MGS's not having a check-valve in the yellow hose. All the hoses in these particular R-1234yf MGS's—including the yellow hose—will be evacuated of air and moisture along with the MGS itself and, of course, the A/C system. This presumes that you're not going to attempt "topping up" the system, which professional MVAC techs ardently discourage—and for good reasons.

On removing the yellow hose from the vacuum pump and subsequently connecting it to a refrigerant source, no vacuum will be lost and no air and moisture will enter the hose because the check-valve will prevent that from happening. So don't worry—there's no need to purge the yellow hose with this type of R-1234yf MGS.

question 2)
are all r1234yf yellow charge hose left hand thread on the can side?

Yes. They're all left-hand 1/2" ACME threads, including the can "tapper" valve if you use one.

question 3)
are all r1234yf yellow charge hose a 1/2 female fitting on the can side?

Yes. Those, too, are left-hand 1/2" ACME threads. This is done to prevent inadvertently connecting R-1234yf hardware to R-134a hardware and mixing the refrigerants.

thank you very much for your thorough response!

I bought a r1234yf can tapper and the threads are 1/4" sae threads. Of course that didnt fit.......this has been so frustrating and confusing getting information. I need to buy another r1234yf can tapper now that has 1/2" acme thread.

I did notice a small valve at the end of the yellow charge hose....well....thats one less thing i have to worry about.

I appreciate your response!

[JohnHere]

I bought a r1234yf can tapper and the threads are 1/4" sae threads. Of course that didnt fit.......this has been so frustrating and confusing getting information. I need to buy another r1234yf can tapper now that has 1/2" acme thread.

Hmmm...I wonder whether the package was mislabeled or something.

When looking for another one, be sure of which design you want: Piercing type or self-sealing can. I'm sure that Tim can get you either one.

[acnoob]

I bought a r1234yf can tapper and the threads are 1/4" sae threads. Of course that didnt fit.......this has been so frustrating and confusing getting information. I need to buy another r1234yf can tapper now that has 1/2" acme thread.

Hmmm...I wonder whether the package was mislabeled or something.

When looking for another one, be sure of which design you want: Piercing type or self-sealing can. I'm sure that Tim can get you either one.

My yellow charge hose is a 1/2” threading.

Question:

I bought r1234yf PAG dye but my car 2019 CRV says it uses POE oil. Is it a problem to put PAG dye in this ac system?