Air conditioning recharge pipe location?

Hi All,

Where are the air conditioning recharge pipes, I have a 1994 Super Custom but have no idea where the charge pipes are, any help would be appreciated!

Thanks

Dan

On the 91 cruising cabin lh 119 it’s down in the front, just lay on your back and poke your head around there and you’ll see them.

On my 93 it is just behind the front bumper

I am having trouble finding the kind of refrigerant used on my 1993. R-22 or R410A. Any way to be absolutely certain?

Hello ‘randywilliamc’ and welcome to the forum.

As far as I’ve been able to tell, my ’93 Hiace with front and rear a/c was originally charged with R-12, which is now banned worldwide, I think.

There may be various stickers that describe the refrigerant type and quantity (in Japanese, obvs).

The fittings on mine were the type used for R12 and I’ve replaced these (my system has zero refrigerant) with modern R-134a fittings. When appropriate I’ll get the system recharged with R-134a. At that time a new desiccant unit and any other parts will be replaced.

I think the system should have 850g if front only and 1400g (+- 50g) if dual, but these are the quantities for R-12. Any good a/c garage should know the equivalent mass for R-134a. R-134a seemingly does not perform as well as R-12 when retrofitted, so the system probably won’t be as cold as intended or will have to work harder.

HTH!!

Btw take a look at the long post in my ‘Show us yours’ page. I hope it’s a good place to start for manuals, resources and parts.

For 1993 it should be R134A. The switch from R12 started in 1992-1995. My wife’s 1993 is 134A.

R22 and 410A are for HVAC systems. R12 and R22 are phased out due to ozone layer issues.

If the quick connect for the 134A low side is different then you still have R12 on your van. They make an adaptor which screws on the top of it so that you can use COTS cans at Walmart and auto parts stores. They cost like 3 dollars.

Good Luck and God Bless
-Bryan

Sorry LH119V. We were posting at the same time. Yours is better haha.

Have an awesome weekend
-Bryan

Hello, All

Here's the sticker that's in mine:


This shows the refrigerant, the mass (for charge) and the high and low side pressures (more useful for top up, I think). I’ve not translated the rest of this.

blgraverly, do you have a similar sticker with the R-134a quantities and pressures? It would be really helpful for when I get my system charged. Thanks!

Good Morning LH119V

Sorry I was out of pocket for a few days. I had to get a procedure done on a place we men don’t talk about. I’m not talking about it haha. Part of getting old I guess.

I looked everywhere for your cool sticker. I have a yellow 134A sticker on mine that is much less informative. I can confirm that the hardware on the van didn’t have the conversion connections which means that if it was converted later…they changed the high and low side charge pipes which seems unnecessary.

I’ll include our sticker, but like I said it’s a disappointment. If you are going to fill by weight, not pressure through manifold gauges, the rule of thumb I was taught was take R12, multiply by .75 and then subtract .25oz.

Please correct the community if I am wrong…this is off the top of my head and I’m rushing to another appointment.

Hoping you’re having an awesome sunny day
-Bryan

Thanks.

I’ve no idea about the mass conversion between refrigerants. If I get the chance to ask someone, I will.

I’d expect the system is optimally designed to operate at specific high- and low-side pressures probably regardless of refrigerant; it’s just that different refrigerants seem likely to have different properties of specific heat capacity (for temp changes) and latent heat capacities (across phase transitions). Oh and ozone depletion properties, of course!

The mass is likely just a way to charge the system, I think. Whenever I’ve had an A/C system filled they add by mass (to the low side I seem to remember as this has a bigger volume) then the refrigerant is distributed once the compressor is run. The simple check is them to look at the two pressures.

I’ve heard that R12 was a more effective refrigerant than R134a (for example). Probably with greater specific and latent heat capacities which might be why later vehicles designed for R134a have bigger heat exchangers, is what I’ve been told.

Your sticker says ‘no oil’. I have some literature to say the Hiace with R12 should have 40-50cc of compressor oil, such as ‘Densooil 6, SUN ISO No 5G5 or equivalent’. Maybe R134a has better lubrication properties than R12, but this is probably moot now.

Anyway thanks for your post and all the best!!

Hey LH119V

Everything you posted is correct. But without manifold gauges, a vacuum pump and a scale. the DIY will just add refrigerant and oil until the low side is in the green range and the registers blow cool. That’s why I am glad you are posting the right way to get the word out. It does make a difference.

And it’s hard to see but it says ND oil 8 which is Denso PAG oil. Looks like “No oil” at first glance. R134A and R1234YF use PAG oil while R12 uses Ester oil. Quantities should be the same.

R12 uses smaller condensers and is more efficient size for size. But they got rid of it and went to R134A and then got rid of it and put whatever alphabet refrigerant is in my new Camaro.

Have an awesome evening
-Bryan

Just curious....when any owners have done a retrofit to r134a, do you change the compressor oil?

I have a 1992 that is an r12 system...but I want to swap it out.

Thanks in advance
JG

Good Morning Gleasman.

If you’re going to use PAG oil you have to drain the compressor. If you use Ester oil you will be good to go, as it’s compatible with the mineral you have in there right now.

Good Luck and God Bless,
-Bryan

Great...thanks for the quick response. I am new to the Hi-Ace community (I have a '92 Super Custom w/ 100k miles). The only thing that doesn't work is the AC...so I am going to do a pressure test and then try to retrofit and recharge with what you recommended!

Hoping this is pretty simple and works.
Any other input is welcome.
JG

blgravely wrote:

Any idea how much of this I should use? I am thinking that maybe 1 can of oil, 1 can of sealant and a few cans of "freon" are the way to go?

THanks
JG

Hey Gleasman.

It holds a ton of refrigerant. 1.400KG to be exact.  That’s like 48 ounces. Almost six ounces of oil too (190g).

So plan on 4-5 cans 134A, and like you were planning one oil, one stop leak.

Front and rear AC on max when you feed it and you should be good to go. 30psi or so on the low side, under 200 on the high side.

Good Luck and God Bless!
-Bryan

blgravely wrote:

Hey Gleasman.

It holds a ton of refrigerant. 1.400KG to be exact.  That’s like 48 ounces. Almost six ounces of oil too (190g).

So plan on 4-5 cans 134A, and like you were planning one oil, one stop leak.

Front and rear AC on max when you feed it and you should be good to go. 30psi or so on the low side, under 200 on the high side.

Good Luck and God Bless!
-Bryan

Bryan,
You seem to be "the man" on this thread - so I am going to address this to you .
Here is my question.  My system is not...seems to have no refrigerant in it, but I have no way to tell.  I was thinking of trying the conversion (adding the fitting kit so the R134a cans will work)...and just putting in the ester oil, and the R134a sealant and refrigerant to see if I could get it cold.  

Do you think I need to vacuum pump out the system first?  The advantage would be that I could test for leaks...but the disadvantage is that I would have to go somewhere to get it done.  

My preference would be to do the conversion (as described above) and see where it gets me.  What am I risking (other than the cost of the chemicals, etc) by not evacuating the system first? If there is little to no risk by skipping that, I am going to.

Thanks again...ready to get this done (my wife is tired of sweating in there)  

Best,
JG

It’s not the best doing it without pulling a vacuum. I would ask where did the other refrigerant go?

However it’s 30-40 years old so there may not actually be a leak. I replaced her compressor not because it was leaking but because the clutch failed horrifically. You could hear it a mile away.

And it still holds a seal perfectly after all these years. Absolutely trouble free.

To answer your question, it will work and blow cold if you do it without pulling a vacuum. The right way is better but it’s not always feasible or economical.

If your system was R12 you cannot mix 134A. Just vent the lines and you’ll be good to go. If it was already 134 even easier. The right fittings should already be on it.

Good luck Sir. If it won’t accept the refrigerant I can tell you how to make it if you are unsure or anything.  This will work, you’ll have a cool van soon.  
-Bryan