Can I test a R12 system with R134a for a few minutes?

[Charrie]

Thanks again for the replies and and sharing your knowledge.
i fell better about the HF detector now..

All of the fittings are spring-loc. none use nuts or flare fittings. I did have to cut some of the fittings off because i couldn't get them apart. When i did the metal parts of the hoses were full of a reddish corrosion. That was part of the reasoning in replacing everything besides the fact that i wanted a trouble free system for years.

Nylog. Isn't the blue rated for R134a and the red is strictly for R12? Seems like that is why i used the red. Maybe has to do with the oils?

I may need help locating the manifold seals O-rings. If i remember correctly they are flat on each side. i may have gotten the new ones in the Santech master O-ring kit i bought but seems like i had to special order them. The original ones were red. But it was not the original compressor when i bought the van because it was a rebuilt compressor.

One of the local parts stores has a standard electric vacuum pump in their loaner tool program. That is what i used last time.

Ok for a question.. Since you guys seem to think it is low on refrigerant and except for the leaking seal, the compressor is probably in good shape, if i replace the compressor and go back with R12, will I need to flush the system? I guess when I pull the compressor and accumulator off i can tell more about the condition of the oil. Also the orifice tub should give some clues?

I think I mentioned this earlier but all of the other connections are dry with no signs of leaking and all of the parts were new. The condenser was a Ford one and the evaporator came from seasons. i would have used the Ford evaporator i found but they wanted $300 for it!

Again thanks and i will be getting the leak detector in the next couple of days.
Charrie

Here is a drawing of my system

[tbirdtbird]

Will re-read the rest of your post on the am.
But for now, red is for mineral oil only, blue is for all types

[Cusser]

Ok for a question.. Since you guys seem to think it is low on refrigerant and except for the leaking seal, the compressor is probably in good shape, if i replace the compressor and go back with R12, will I need to flush the system?

I personally don't think that you'll need to flush the system - you don't have metal particles in your system with a seal leak, unless the low refrigerant/oil caused compressor noise or seizing. Do the work on one day, and replace the drier/accumulator.

[tbirdtbird]

Cusser, I would like to agree with you.
All the while, this statement from the opening post, I find concerning:
"The compressor is noticeably louder then it was last year"
So I am on the fence.

[Charrie]

Thanks guys.. The noticeably louder appears to be with the hood up working around it. From inside the cab I have to roll the window down to hear it. if that helps at all.

Will the orifice tube and color of the mineral oil in the compressor and accumulator tell us anything?

I blower fan is making some noise on high like it is out of balance or something but runs fine on low and med. Last yer there was water dripping down the firewall on the outside and then coming inside through a seem where it would puddle in one of body mount bolt holes. Only a little though. The point being even though it may just be the drain tube clogged, I wouldn't object to having to remove the evaporator and clean everything out inside.

If I understood correctly, there are shops with machine that can flush parts with R134a? If so then I would have the condenser and evaporator flushed at one of those places.

Now the easiest thing for me would be to just test for leaks, fix any besides the compressor if there are any, replace the O-rings, replace accumulator and orifice tube, then charge the system. In my older age I am a bit slower at being able to do some things and depend on my young son who is pre-occupied with his new GF at the time and so the easier route would probably be best.. BUT I would like this to last another 6 or more years like in intended it to the first time!

So perhaps some pics of the oil and the orifice tube for you guys might help?

Also while working it last week and getting it to accept the 10 ounces of refrigerant, around that time is when i noticed it much louder.

Thanks
Charrie

[tbirdtbird]

1. pic of the OT would def help
2. it is nearly impossible to properly flush a condenser, so a new one is about $100
3. I am fairly certain a so-called flush with 134 won't work, it will all be in the vapor state. You would need a liquid flush. Also, a flush with 134 would be illegal, you are not allowed to vent refrigerant like that any more. Heck in the old days rooftop techs would blow debris out of condensers using jugs of R12, the stuff was only $15 bucks a jug back then. Those days are over

[tbirdtbird]

Look here for links to flushing and charging

https://www.autoacforum.com/viewtopic.php?f=3&t=14447

[Charrie]

The article i was reading said they hook up a recovery type machine and flush the system with R134 unless I misunderstood.

Ok will get pics soon..

There are no drop in replacement condensers available for under $300 right now! I found a parallel condenser that I believe can be modified to fit but would require adapting the tubing and fittings. Then the warranty would be void. The condenser sits in a recessed space just in front of the radiator and there is no space to push it out towards the front grille because there is a transmission cooler in the every front.

Thanks
Charrie

[Charrie]

Ok guys, an update here. After 2 different HF stores and 100 mile round trip, I bought 2 of the HF leak detectors in case one was bad. I can take the other back to the local store who claimed to have them in stock but didn't. One did seem to work a little better then the other and I will keep that one.

I could only find 1 leak and that was at the compressor which we knew was leaking. I could not get the detector wand up inside the evaporator drain but I did close all of the vents except the one that went directly into the evaporator housing and turned the blower on low with the ac selector on max AC.

As to the condenser, I couldn't reach all of it because the transmission cooler is in front of one corner of it but did go over it 3 times and found nothing.

I only hooked up the high side because it is easy to get to and the high side gauge was showing almost 90psi so that should have been enough for testing?

The leak detector did not show a leak at the compressor until I used a large over it like suggested. After the baggy had been in place for 5 of 10 minutes, I cut a small hole in one corner and before I could get the want inserted, it was squealing.

So what do you guys recommend from here?

My system used 54 ounces of refrigerant. This may sound stupid, but, is it possible to pull a vacuum on an empty 30lb (maybe 2), tank and pull out most of the freon? I am having trouble finding anyone within a 50 mile radius that still has equipment to recover R12. I saw a video where a guy used a old refrigerator compressor and empty tank to recover his refrigerant. I have an old window AC with a good compressor but bad fan.. I could solder a couple of fittings on to it.. If that wold work?

Again thanks for taking your time to help and advise me with this.
Charrie

[Cusser]

My system used 54 ounces of refrigerant. This may sound stupid, but, is it possible to pull a vacuum on an empty 30lb (maybe 2), tank and pull out most of the freon? I am having trouble finding anyone within a 50 mile radius that still has equipment to recover R12.

I have used my vacuum pump and a small canister no longer needed by my workplace to recover R-12. Nowadays, I'd have to buy dry ice to do this; I'd use surplus from work back then, and use waste alcohol from the lab.

I installed an AC fitting to my canister. I pulled vacuum on the canister to remove any remaining refrigerant or air, then close its valve. I'd put the canister in the freezer. Then I'd put the canister in a dry ice-alcohol bath, attach the canister to the vehicle AC, open the canister's valve, and its vacuum would start to pull over refrigerant. As refrigerant arrived into the cold canister, it condensed into liquid refrigerant, so still was under vacuum, so more refrigerant came over, etc. When complete, I'd shut the canister valve; when filling, I'd just fill from the canister. I'd weigh the canister before and after so I'd know how much refrigerant was recovered.