I just spent more than few of the remaining minutes I have left talking to an eBay agent(?). I was bitching (of course) about a confirmed order for 2 - 1993 240 A/C condensers canceled by the seller. I guess I should have known the beater did not have any either, whenever all the usual sources had dried up.

So, here I sit with a cooked A/C compressor after some moron filled it with 2.07 lbs. of R134a instead of 1.63. "A little extra Freon didn't hurt anything - you're allowed +/- a half pound.",sure, and the A/C clutch smoked itself while the compressor puked out its oil just for the hell of it.

The common wisdom seems to be to install a new condenser with a compressor exchange.

Since I have not been able to find an replacement condenser, what should I do? Is there another condenser out there of PROPER capacity which can be plumbed in place of the correct part? Or, can a used 1993 240 condenser be flushed well enough to be reused?

As usual, any help will be appreciated.

Rich (near The Burgh)

Hi,

Just so you know you are going to have to replace or at least clean the orifice tube as well!

The orifice tube has screens to catch the majority of things that should not be in the system.
Past that, the accumulator has a screen and the desiccant itself to hold debris.

So throughly cleaning out the original condenser is a common practice. Of course, the optimum word here is "throughly!"

You want to use a solvent to break down any oil along inside the tubing. You want flush it back and forth through the opposite ends. The liquid moves things.
It would also be a nicety to use a dry nitrogen, argon or even compressed air that was ran through an refrigerated air dryer. Auto body shops use them to dry the air out before using it to push their paint out their spray guns.

As a suggestion, You just might take it to a body shop and have them do it for you. They have all the solvents and permits to use them.
If you are lucky to find a shop, that may want to later get a paint job or "detailing job" out of you, will do it for maybe $20.
They should be able to use less solvent as they can blow it through and recover it through a filter cloth or a canned recirculating filter.
They always have used solvent around from cleaning their guns in special machines. Of course, the final blow through needs to be done with a fresh virgin solvent pass.

You will want to avoid moisture as much as possible. While the system is open tape off the open lines or use rubber plugs
Also do a warm vacuuming of the system before recharging. Either on a hot day or use a hair dryer or heat gun along any place use can reach with it.

As far as oil charge just put the amount in needed for the compressor only. You probably have plenty else where, left in the low lying lines of the evaporator or the accumulator.

Im sorry you are having so much trouble but it sure sounds like you are running through a rough patch of things that should have not happened, with the overcharge two ways!

It's getting where, even, if you really don't know what you are doing completely, you are better off learning to do it yourself.
The outcome is more controlled with out paying for someone else's HARD KNOCKS education or mistakes.
Sounds like it had a flood back moment and it only takes one!
This system is a "critical balance" charge system as there is no "receiver on the high side" for the excess refrigerant he is talking about!
These maybe old cars, when you first look at them but Volvo was ahead of doing things! More so, than most car makers of the time, even though they let being cheap get too them! IMHO

Phil

There are some pretty good links in this currently changing thread about 93 240 AC on TB http://forums.turbobricks.com/showthread.php?t=343672 and this one includes some of the part numbers that make 92 vs 93 differences, along with cutoff chassis numbers.

Nothing about where to get a condenser though...

Phil, I remember the emphasis on getting all the oil out being made when conversions from R-12 to R134a were being made with the PAG oil and not the ester oil more compatible with the mineral oil carried by the r12. I realize it has to be oil free when the oil contains acids from a stationary system burnout (enamel motor windings) and the solvent before the Montreal Protocol was R-11, but what is the need for complete oil removal in a native R134a system like the '93 came with?

I'm not being skeptical as much as wanting to learn, as I've never seen what happens downstream when an automotive compressor locks up, and can only imagine what might be present in the orifice screen. In my 4 semesters of HVAC training we used nothing but R134a (and N2 to flush) but we didn't burn things up either to get that kind of practical experience. Just the usual pursuit of the unanswerable question "how can we know when it is charged correctly" for those cap tube and fixed orifice evaporators.

When you explained (in another post) how forgiving the old TXV AC's were, it reminded me of how new it seemed to "charge by weight" calculated by the engineers who knew all the pipe sizes and expected temperature differentials. How do so many of the weekend mechanics get away hot-shotting their R134a cars with a kit from Walmart without breaking their compressors?
--
Art Benstein near Baltimore

Life is like a roll of toilet paper.
The closer you get to the end the faster it goes.

Hi Rich,

Your unattributed reference to "common wisdom" reminded me of an old aphorism about "common sense." Perhaps when money thrown at a car was the most efficient method of assuring a first-time fix, it was a good practice to throw in a new condenser, but now you're dealing with a 25-year-old antique made one year only, and trying to source parts as if it were the Honda Accord made 10 years ago.

So flush it, why not. *you asked*

If you see metal coming out of it, flush it some more. Maybe tear down the dead pump and find out what it could have loosed on its output target.

Mostly I was curious about the rant including an excuse about some sort of tolerance for overcharging an accumulator/CCOT system and whether "moron" was appropriate for anyone who measured refrigerant to 3 significant figures. Sounds like maybe a professional, from which one would expect some sort of responsibility financially.

Anyway, all friendly on my part, and sympathetic to your pain, as we hope for some cooling to accompany the currently approaching front which has already passed you in the Burgh. In other words, I have no answer. :)
--
Art Benstein near Baltimore

Wise men speak because they have something to say; fools, because they have to say something -Plato

I guess I was ranting, wasn't I? But . . .

I listened to the mechanic's running commentary as he composed his bill,"Orifice tube (he really called it a "filter tube"), $54.23 (YIKES!), 2.1 pounds of Freon . . ." At that point I interrupted him by telling him the a/c sticker said 1.6 pounds. He told me that I was wrong and that amount was for the "old" refrigerant.

So, I figured he knew what he was talking about since he was the guy who had that expensive recovery machine with the digital display in one of his bays.

As I idled the car to see how well the A/C was cooling and, since I had the console kick panel removed already, reached in to feel the evaporator, he said it would start kicking by the time I drove a couple of miles, "those old cars don't cool like the new ones" don't cha know?

Filled with trepidation but fully realizing how ugly this type of dispute can become, I drove off. And, in a couple of miles, the A/C REALLY did start to kick, if the definition of kicking was for the compressor to slug away while it burned up the clutch.

When I returned with the remains of my A/C smoldering under the hood and pointed out the refrigerant sticker on the radiator core support, he STILL insisted it took 2.07 lbs. A light bulb finally glowed dimly over his head when my finger slowly trace the line on the sticker which read, "Recommended charge: 200 Series .75 Kg.(1.63 lbs) R134a".

That was when he pulled the +/- 0.5 lbs. tolerance out of the ether, but an offer to repair the damage hung resolutely out there in space.

Although "moron" might sound a little harsh, I'm at a loss for words.

There's an old Sicilian aphorism, and, believe me, Sicilians have one for any situation: He might know the song, but he doesn't know the music.

To think I didn't have the time to replace a leaking o-ring which I tracked down and recharge the system. Now, I have to flush out the system, install a new orifice valve, accumulator and compressor then charge it. I guess it's time to find one more thing to do myself.

Rich (near The Burgh)

What a horror story. I imagine exactly this happening to me the first time I take one of our Volvos to someone else to work on.

The last HVAC course I took at the community college culminated with the battery of tests for the State Journeyman License. Most all the other students were employed by businesses around the area engaged in work for commercial or residential HVACR. Not one had or desired to have automotive AC work. My guess is the experienced automotive AC techs are found a lot further South of the Mason-Dixon line than I am.

At the least, if I screw it up, I can't be too angry.
--
Art Benstein near Baltimore

Most would rather be ruined by praise than saved by criticism.

The performance of your system will be improved/enhanced by the addition of a contemporary condenser. Simply buy the BIGGEST one that you can make fit with the plumbing bits where you need them to be. The more easily you can reject heat (the condenser does this), the easier it is to cool things down inside. I pulled all the Volvo HVAC components out of mine (82 - before the A/C worked very well in SE US) and went aftermarket. I use a Classic Auto Air 15"x21" condenser if memory serves. Don't make it hard -- get the biggest one you can make fit. You'll thank yourself later.

The good folks at Classic Auto Air told me -- "24 ozs of 134A, no additional oil -- and if you have to err, err on the side of too little freon, not too much. " I used a scale capable of measuring in very small increments. And getting all I could out of 2 12 oz cans of refrigerant, I totaled 23.2 ozs of freon. Called that good enough.

If the poster up sizes the condenser, I'd start with the recommended weight of 134 for the stock system. And then add just a bit at a time -- over an extended period of time -- to see if performance improves. Not even sure I'd measure the additional amount. I'd just get one of the "fill up your freon" cans with the push-button thingy on the hose -- and add just a little bit at a time and carefully monitor performance. One thing seems certain -- too much is worse than too little in this scenario.

Having long been envious of the carefully planned and executed aftermarket replacement kit in your V8, Michael, I wonder if the sizing of the components included the sizing of the charge (down to 3 significant figures *grin*) and how many folks have just taken advice to upsize condensers in existing R134a CCOT configurations without accounting for the capacity in refrigerant weight? A hot topic this month I'm sure.


--
Art Benstein near Baltimore

"To do is to be." - Descartes
"To be is to do." - Sartre
"Do be do be do." - Sinatra