Automotive Air Conditioning Information Forum (Archives)

Provided by

We've updated our forums!
Click here to visit the new forum

Archive Home

Search Auto AC Forum Archives

How big a condenser

Mike W. on Sun June 29, 2008 1:34 AM User is offline

Year: 80
Make: BMW
Model: 528i
Engine Size: 3.5

I know condenser size is critical to performance, but how big is big enough? I don't have the OE specs at hand for my 528i in question, it performed fairly well with R12 in the original configuration, but not great, I could see 42F vent temps in the desert, but it took a while to get down to temp. Original condenser was a serpentine, I'd guess about 14" X 18" but I don't have the specs at hand. I could source an original one, but after gas and time I doubt it would be any less for a used one than a new parallel flow condenser of say 14 X19 or so. Plus a new one would likely perform better than one pushing 30 years of age just due to clean metal and better heat transfer. I'm undecided on the refrigerant as of now, but I doubt it wll be 134a. Maybe 12, maybe something else. I know bigger is better in condensers, but I'm kind of limited by the space I have to work in. So does 14 X 19 sound like it's large enough for a medium size car? Plenty of glass, but relatively vertical front and rear windshields so at least I'm not fighting that part of it.


TRB on Sun June 29, 2008 2:11 AM User is offlineView users profile

install the largest PF condenser you can fit in the space available. Take into account you need a little room for fittings and hose.


When considering your next auto A/C purchase, please consider the site that supports you:

bearing01 on Sun June 29, 2008 12:18 PM User is offline

Which compressor do you have on that car? Depending on the flavor, you may want to redo the compressor seals. Some of the old compressors have incompatible seals that will leak after exposed to R134a for a while. Some R12 compressors put out in the late 80's/early 90's came with R134a compatible seals.

I'm currently going through the AC on my 1986 325es project car, retrofiting it to R134a. The PFC is the better route. However, factor into your budget the new hoses you'll have to make in order to hook up that new condenser. Also wouldn't be a bad idea to replace all the hoses with new barrier hoses. Much cheaper to have the hoses made than to try to buy them at the dealer. To replace BMW OEM hoses would probably cost more than the car is worth. You can buy bulk hose from at length and as well as the fittings. Then buy a beadlock crimper or bring the hoses to a shop to do the crimping.

Another thing to keep in mind with the new condenser is how the auxilary fan mounts to the old condenser. On my 1986 the fan mounts to the condenser. You may want to make sure the PFC you get has a strip of metal across the top & bottom that you can fit some flat bar or angle iron to so you can rig up a mounting bracket for the aux fan.

Mike W. on Sun June 29, 2008 1:57 PM User is offline

I'll be using the original type Bosch swashplate compressor, I like them a lot better than the later wing cell ones. It's going to be a complete system rebuild, with an E28 evaporator box, later condenser and all new hoses of course. I've had pretty good luck just cutting them to size and using a double hose clamp on it, a technique I've been using for almost 20 years now. Barrier hoses are a good idea regardless, and I think all you can buy now anyway. But I doubt I'll be using 134a, I don't want marginal performance, so I'm not so worried about the compressor seal. Thanks for the input regardless.

94RX-7 on Wed July 02, 2008 2:53 PM User is offline

A friend of mine ordered a new condenser from BMW for his 1993 325is and the part they sent was a parallel flow unit. The original was a tube and fin design. You might check with BMW to see if their updated part is a parallel flow unit....then it would just bolt right up, no fuss, no muss.

Back to Automotive Air Conditioning Forum

We've updated our forums!
Click here to visit the new forum

Archive Home

Copyright © 2016 Arizona Mobile Air Inc.