Air Conditioner Recharging

JonathanS · #1 05-22-2005, 08:33 PM

What is the proper refrigerant pressure in the A/C system of a 1996 LSi?

I seem to have an A/C leak in my recently purchased SVX When I inspectd it prior to purchase about a month ago, the A/C wasn't working. The seller said that it hadn't been recharged in several years, We agreed that she would have the A/C recharged and inspected to make sure that's all it was. The shop put UV dye in the system and reported that there were no leaks visible. When I closed the deal and picked up the car, the A/C was working fine.

About two weeks later, the A/C stopped working. Since the shop that did the original check is over an hour's drive from my home, taking the car back there would involve taking a day off from work, so I can't realistically take it back there.

Today, about a week later, I purchased a UV lamp but didn't see any signs of a fluorescent dye. I then bought an Interdynamics recharge kit with guage and also some UV dye. I added the UV dye (thinking that perhaps the garage's dye had been worn/washed away) and let the system run for about 10 minutes, per package instructions. Still no leaks visible.

I did check the refrigerant pressure, however, and it was low, at around 18 psi. I recharged it to about 27 psi. I think the 19 oz. refrigerant canister ran out at that point. The Interdynamics packaging said that the "filled" range is from 25-45 psi at 75-85 degrees F. Since it was about 68 degrees when I filled the system, I figured I had added enough.

Did I? I don't have a shop manual, and I couldn't find any A/C specs in the owners manual.

I plan to check for signs of fluorescent dye and keep track of the A/C sytem pressure a couple of times this week. I would appreciate input from fellow owners on the following:

-- What is the proper A/C system pressure?
-- Why am I not finding leaks? (I am guessing that there is an internal leak, say in the compressor or elsewhere, that is collecting the dye internally.)
-- I also picked up some Interdynamics two-part A/C leak stop. Part one is supposed to fix metal-to-metal leaks and part two is supposed to fix rubber leaks. Is there any reason not to just dump it into the system?

Thanks in advance from a novice A/C tech ...

thundering02 · #2 05-23-2005, 01:00 PM

If it hasn't been charged in several years then it may still have R-12 system which is illegal to produce now you'll need to spend the money to convert to r-134a and then have it charged.

#3 05-23-2005, 01:40 PM

Look at the sticker in the car.

Earthworm · #4 05-23-2005, 01:49 PM

His is a 96 so it will have R134 as opposed to R12. Only 92's has R12.

SVX-FF · #5 05-23-2005, 03:45 PM

Quote:

Originally Posted by Earthworm

His is a 96 so it will have R134 as opposed to R12. Only 92's has R12.

Well thet just sucks for us 92'ers dont it.

Steve

#6 05-23-2005, 04:53 PM

1. you may have a leak in the portion of the system which is in the dash. if so, it is a pain in the butt to get to.

2. my mechanic does NOT like the leak seal stuff because he has been told that it can much up his discharge a/c recharge system. i presume it works for small leaks, but if a tech ever has to drain the system you may have a problem of having the shop refuse to do it if they know you have the stop leak in the system or have the moral issue of not telling them and harming their equipment.

michael · #7 05-23-2005, 06:08 PM

Refrigerant type and capacity are on a sticker on the radiator support.

Earthworm · #8 05-23-2005, 06:24 PM

Quote:

Originally Posted by SVX-FF

Well thet just sucks for us 92'ers dont it.

I've got my retrofit kit...I just need to install it. (read: lazy)

michael · #9 05-23-2005, 06:46 PM

Quote:

Originally Posted by Earthworm

I've got my retrofit kit...I just need to install it. (read: lazy)

Can you describe said retrofit kit?

n00b on demand · #10 05-23-2005, 07:20 PM

Ill be getting my system recharged next week.

#11 05-24-2005, 12:11 AM

Quote:

Originally Posted by SVX-FF

Well thet just sucks for us 92'ers dont it.

Steve

It only sucks if you need to fix it. If it's working properly it's colder than 134a.

Earthworm · #12 05-24-2005, 11:02 AM

Quote:

Originally Posted by michael

Can you describe said retrofit kit?

It's a bunch of o-rings, the 2 fittings and a replacement sticker indicating R134. I also have a replacement dryer.

I'd still need to replace the oil in the compressor.

freak customs · #13 05-24-2005, 02:19 PM

Quote:

Originally Posted by THAWA

It only sucks if you need to fix it. If it's working properly it's colder than 134a.

normally i would agree. however i converted mine to 134a and got it to throw ice cubes at me

my thermometer says it's blowing 50 deg from the center vents (gunna get another thermometer to confirm that tho).

dcarrb · #14 05-24-2005, 02:43 PM

I've read a number of posts maintaining that R134a isn't as cold as R12, but mine has been converted, and after a couple of minutes of operation, the air from the system is uncomfortably cold on my hands, to the point I have to aim the vents away. In hot, muggy Georgia, no less. Perhaps, technically, there is a degree or two of difference between the two, but in practical terms, 134a is certainly up to the task.

dcb

JonathanS · #15 05-24-2005, 08:13 PM

As noted, my 1996 a/c system is R-134a.

How do I check the part of the a/c system inside the dash?