W126/116 AC condensors and maxing performance...
 

Well since my SDL is driving me crazy now, I'm going to finish on the SD's system here. Anyway, since that system is 100% dead I'm going to go through it all here. Which brings up some observations/questions...



A parallel flow condensor seems to be a pretty inexpensive upgrade for these vehicles. Maybe $120 for the unit and hoses, wouldn't this help even on an R12 system? More capacity and efficiency... Now are there only universal condensors there or is there a place that sells direct fit units?

Who has one of these in their W126 with R12? How did it help sitting at idle?

Also, for the W126s at least we can use the late ~'90+ dual front aux fans to help keep high side pressure down and push more air. Shouldn't be too spendy once you find them. For the W116/123s you'll probably want to upgrade to a larger aux fan.

Here's a few threads I have found...



http://www.peachparts.com/shopforum/tech-help/81979-parallel-flow-condensor-installed-w123.html?highlight=parallel+flow+condensor

http://www.peachparts.com/shopforum/diesel-discussion/99598-1982-300td-r134a-conversion-parallel-flow-condensor-update.html?highlight=parallel+flow+condensor

Down there, you can certainly make the case that a parallel flow condenser would be a worthwhile addition to an R-12 system. If the cost is as low as $150., I'd certainly do it. Why bother with a 20 year old condenser with unknown heat transfer capability through it's tubes??

Now, up here, I'd probably save the money.........we hit 90°F. about four or five times per year.........and 100°F usually happens every two or three years. The R-134 systems are adequate for this task, even with the old condensers.

I am not too far from Arlington Tx. I live in West Monroe,LA about a 5 hour drive and our weather is similar to yours. My car is a 86 300sdl with a retrofit to 134A. I have no problems with keeping the car cool unless it sits all day in the 95 degree heat. Then it takes about 3 miles on I-20 to cool it down, but so does our Honda Odyssey. My daughters 2000 Toyota Camry blows ice cubes sitting in the parking lot just after I start the car!!! There is something about Toyota Air conditioning.
I did notice that the last Tech that checked my A/C had my system a little overcharged in the Benz. I released some and it cools a lot better. I guess that is because the 134A expands more?
Anyway, my Dad has a 380SE with a 134A retrofit and he tinted his windows and that helped a lot. His car being an 85 does not have a recirc button like my 86 does. One thing I checked and replaced were my vacuum actuators for the main outside air flap. They were not closing all the way when the recirc button was pressed in.
I am tempted to go to the new type condenser when my system fails, but until then I am leaving well enough alone.
Oh, another thing that helped my A/C was blowing the crud out of my evaporator drain lines.
John

Well I'm going to replace the Evaps in the SD and the SDL as both dashes are cracked, makes sense while I'm in there. I've seen pictures of how much crap can get up into those...

I priced the direct fit tube/fin condensor for the S-class and heck, the parallel flow is cheaper if you don't mind some slight modification to make it fit properly.

The A/C will be working in the SD or the L before I tackle this. One of them will be the first with the parallel flow setup in my stable. I wonder if this will keep vent temps in the 40°F range in traffic with a clean evap core and extra R12. :confused: