AC Condensers And Parallel Flow

[kings1527]

So it seems like our original AC condensers are getting tough to come by. The original serpentine design was extremely efficient and the AC design in the DeLorean was excellent from day one. In terms of efficiency, I've discovered this:

1) Tube and Fin (least efficient and oldest technology)

2) Serpentine (pretty good performance. OEM in the DeLorean)

3) Parallel flow (best performance, about 30% more efficient and recommended for R134a)

Currently, no vendor has a parallel flow condenser. There are some aftermarket ones for the DeLorean floating around out there but they all seem to be Tube and Fin. I definitely am not interested in going backwards with technology.

Personally, I'm not interested in changing up anything within the stock AC system since there's no need to and I'm surprised no one has come up with a suitable parallel flow replacement since that's the best technology. I'm guessing it's simply a cost issue coupled with the fact that parallel flow is new technology within the last 15 years. It seems like the DeLorean's AC condenser is a low-frequency replacement item. AT LEAST come up with a serpentine replacement condenser. Just take care not to torque your original fittings too much. :rolleyes1:

It seems like there are a TON of universal fit parallel flow condensers and I can't imagine it would be an impossible thing to find for the DeLorean. Everything on our AC system seems to be pretty standard sizes. Has anyone tried putting in a parallel flow condenser? It would be really interesting to see someone do it who's running r134a since they say you get the best heat exchange with r134a and a parallel flow.

I need to get home and get the dimensions of the OEM condenser on the car and do some homework online and see what I can find online with a parallel flow. There are tons of universal condensers out there.

Someone mentioned that hoses need to be changed/upgraded when going to parallel flow. Does anyone know why?

Basically, has anyone tried parallel flow and if not, why?

If you're not using an OEM condenser, what are you using and are you happy with it?

[Tillsy]

I've been waiting to replace my condenser. Was told Houston were working on a new one. ETA February 2013...

[kings1527]

Lol.

Well, I definitely don't have that kind of time, since they're already 15 months behind schedule. And it's still listed as 'In Stock' on the website.:dunno: I need AC in my car.

There are a gaggletroop of condensers out there and I'm going to do some legwork and try to find one that's a good fit with at least equal performance, hopefully parallel flow. I'm thinking a parallel flow condenser would yield even better performance, particularly with R12 which is what I'm using. I'm also not interested in going with something that's a different size since that will change the charge amount.

[David T]

It may not be the newest technology but you should be able to find used ones. They don't wear out, they either get contaminated or someone damages a fitting. Try Sheriff Bob.

[kings1527]

It may not be the newest technology but you should be able to find used ones. They don't wear out, they either get contaminated or someone damages a fitting. Try Sheriff Bob.

Thanks David. Not sure if I know Sheriff Bob. Do you mean Video Bob who does the BTTF conversions?

[David T]

Thanks David. Not sure if I know Sheriff Bob. Do you mean Video Bob who does the BTTF conversions?

No, Sheriff Bob in North Carolina. He advertises all the time in HMN. 919-477-7516 He has a lot of used parts. Really nice guy.

[kings1527]

Excellent. Thanks so much for the lead.

[dmc6960]

I see no reason you couldn't do the universal parallel flow.

In 2005, Hervey sold me a tube and fin condensor. In 2012, he sold someone else a parallel flow. See this thread starting here...
http://dmctalk.org/showthread.php?5004-Misplaced-my-2-O-rings-for-the-water-pipe-Y-pipe&p=71225&viewfull=1#post71225

The condenser has a row of mounting holes on the top and bottom. Looking at the pictures of the one from Hervery, it appears those holes must have lined up perfectly with the mounting tabs on the radiator, because they dont look custom drilled. Actually one side is enlarged to get the bolt through, then a locking/spacing nut tightened down on it. Just needs another nut and some washers and you have a mount to the radiator.

Here is the exact one you want (12" x 27")...
https://www.ackits.com/pc/12-0440C/Parallel/12-0440C+-+FSHE+PF+Condenser+%2812+X+27%29

It seems they also have an "economy" painted condenser. I would not recommend this one as the paint would act as an insulator with the heat exchange through the air. The paint could also be used to protect inferior metals, and it appears to be the one Hervey sold...
http://www.ackits.com/merchant.mvc?Screen=PROD&Store_Code=01&Product_Code=CN20010XC&Category_Code=

Unfortunately I cannot give you a 100% personal guarantee as to its fit and function. I like to do that before recommending things but unfortunately here I cannot. I'm still running the tub and fin condenser I got from Hervey in 2005, and I'm waiting for something with my AC to fail before replacing it. 8 years now after the complete rebuild and I haven't had to do anything, not even top-offs. I'm unsure why the end fittings would be any different sizes. They are fairly standard in this application.


Fittings Industry Standard Female O-ring
#8 (13/32) & #6 (5/16th)

[kings1527]

I see no reason you couldn't do the universal parallel flow.

In 2005, Hervey sold me a tube and fin condensor. In 2012, he sold someone else a parallel flow. See this thread starting here...
http://dmctalk.org/showthread.php?5004-Misplaced-my-2-O-rings-for-the-water-pipe-Y-pipe&p=71225&viewfull=1#post71225

The condenser has a row of mounting holes on the top and bottom. Looking at the pictures of the one from Hervery, it appears those holes must have lined up perfectly with the mounting tabs on the radiator, because they dont look custom drilled. Actually one side is enlarged to get the bolt through, then a locking/spacing nut tightened down on it. Just needs another nut and some washers and you have a mount to the radiator.

Here is the exact one you want (12" x 27")...
https://www.ackits.com/pc/12-0440C/Parallel/12-0440C+-+FSHE+PF+Condenser+%2812+X+27%29

It seems they also have an "economy" painted condenser. I would not recommend this one as the paint would act as an insulator with the heat exchange through the air. The paint could also be used to protect inferior metals, and it appears to be the one Hervey sold...
http://www.ackits.com/merchant.mvc?Screen=PROD&Store_Code=01&Product_Code=CN20010XC&Category_Code=

Unfortunately I cannot give you a 100% personal guarantee as to its fit and function. I like to do that before recommending things but unfortunately here I cannot. I'm still running the tub and fin condenser I got from Hervey in 2005, and I'm waiting for something with my AC to fail before replacing it. 8 years now after the complete rebuild and I haven't had to do anything, not even top-offs. I'm unsure why the end fittings would be any different sizes. They are fairly standard in this application.

Jim, that's exactly the info that I was looking for. I was JUST getting ready to look up a 12" x 27" from ackits when I saw your reply. Thanks! I had to get home first to measure the OEM.

I'm going to give it a shot and report back. This week would be the perfect time to test it out; we're getting 100 degree temps right now.

It's tough to tell from the pic on ACkits, but I'm guessing the universal holes are on the top and bottom of the condenser. I'll get the mounting bracket set for $10 just in case but as it turns out, they are backordered on the 12" x 27" condenser. In the meantime, I've located an OEM so I'll put that in. But I'm still very curious about putting in a parallel flow and see how it does.

Have you been happy with Hervey's tube and fin? Did you notice a performance difference from the OEM?

I like the fact that the one from ACkits will be the same size and therefore not cause a change in the charge amount of 2.2 lbs for the car. I'm hoping parallel flow will give even better performance with R12 and if for whatever reason I decide to go to r134a, I'll be all set.

Billy on the other thread said he measured out the width at 27 1/2" exactly, I measured mine today at 27 5/8", and the unpainted version at ACkits measures out at 27" according to the website. There appears to be a little difference in dimensions and hopefully that doesn't cause problems.

[Tillsy]

I for one will be very keenly awaiting your results! :)

[Farrar]

I'm watching this thread carefully since it's getting warm down here and the condenser is the one piece of equipment in my R-134a-converted system I didn't replace (yet)... the bottom of it is a little frigged near the hose connection, but it didn't leak so I just left it in place and put the new hose on extra-carefully...

[kings1527]

I'll let you know when I get ahold of the parallel flow condenser that looks like will fit in the car. The PF is backordered right now and I have an OEM condenser in transit which should be here next week. So, worst case scenario is I'll go with the OEM if the PF doesn't pan out since the original design was outstanding. ACkits says they've been backordered for about a month and a half and they're on a 'truck' right now (or a boat, depending where they're manufactured, I guess). I'll check back with them weekly.

I'm also entertaining the idea of having a custom PF condenser made and I think it'll be upwards of $300 or so. But I think the 12" x 27" from ACkits will work. That one might be SLIGHTLY smaller than the OEM so if it turns out to not be the best fit, I might have one made up to exact OEM specs in a parallel flow.

[kings1527]

So, I found another that I'm going to give a try.

http://www.acsource.com/highefficiencypflowcondenser12x2734.aspx

It actually looks exactly like the one Hervey sold Billy back on this thread:

http://dmctalk.org/showthread.php?5004-Misplaced-my-2-O-rings-for-the-water-pipe-Y-pipe&p=71225&viewfull=1#post71225

I might just be running around in circles trying to find one when I could've just gone through Hervey I guess. I'm very interested to see what the deal is performance-wise with a PF.

The one non-painted version from ACkits is made of 'high grade aluminum', but it's not in stock. I wouldn't mind waiting for it but the one from acsource is 12" x 27 3/4" from the end of the fitting to the edge of the mounting bracket. The other one from ACKits is 27" even, according to the website. I measured 28 5/8" on the OEM condenser. The one from acsource is probably a more exact fit but it's painted. Hopefully it's anodized which would be better for heat transfer. Regardless, the improvement in technology with PF should translate into better performance even though it's painted. When it comes down to size, it makes no sense to have one custom made for $300 or so and have it be less than an inch wider and closer to OEM spec when I can have this one for $125 including shipping and no tax. Less than 1" shouldn't be a problem. The one from ACkits was further off in terms of dimensions and I want the condenser to line up as close to original as it can because of the fans and the hoses.

Absolute worst case: out with the PF and in with the OEM serpentine, which I was VERY happy with before!

[dmc6960]

Have you been happy with Hervey's tube and fin? Did you notice a performance difference from the OEM?

You felt the air last year at the DMCMW open house when we drove to the dinner, remember what that was like?

When I did my AC rebuild in 2006, I also replaced my OEM radiator (with a Hervey replacement) and Toby's (1st gen) replacement fans.

Old Condenser - Serpentine - Good
Old Condenser - 100k miles, dirty - Bad
New Condenser - Tube and fin - Bad
New Condenser - new and clean - Good

Comparing 100k old serpentine to new tube and fin is probably a wash. New serpentine or new PF would be better.

Another major factor in my current AC performance, Toby's 1st gen fans. They are a universal s-blade fan, attached to the radiator with a custom bracket, and no shroud. This results in much poorer performance on low/no speed as neither the radiator nor condenser is being fully utilized. Though my engine has never overheated with this setup, there is a very noticeable difference at idle where my AC does warm up a bit (50s vent output). It still drops down to the low 40s, sometimes upper 30s, at highway speeds (and using r134a).

My eventual upgrade path will once again replace the entire front-end heatsink assembly. New PF condenser, new all-aluminum radiator from DMCEU (seems to be the current favorite among everyone), and Toby's current replacement fans, bringing back use of the OEM shroud.

[Andrew]

Hey Kings 1527:

Did you ever receive and install the parallel flow condenser from AC Source? If so, what were your results in terms of fitment and vent temps?

Thanks,

Andrew
4194


Thus
So, I found another that I'm going to give a try.

http://www.acsource.com/highefficiencypflowcondenser12x2734.aspx

It actually looks exactly like the one Hervey sold Billy back on this thread:

http://dmctalk.org/showthread.php?5004-Misplaced-my-2-O-rings-for-the-water-pipe-Y-pipe&p=71225&viewfull=1#post71225

I might just be running around in circles trying to find one when I could've just gone through Hervey I guess. I'm very interested to see what the deal is performance-wise with a PF.

The one non-painted version from ACkits is made of 'high grade aluminum', but it's not in stock. I wouldn't mind waiting for it but the one from acsource is 12" x 27 3/4" from the end of the fitting to the edge of the mounting bracket. The other one from ACKits is 27" even, according to the website. I measured 28 5/8" on the OEM condenser. The one from acsource is probably a more exact fit but it's painted. Hopefully it's anodized which would be better for heat transfer. Regardless, the improvement in technology with PF should translate into better performance even though it's painted. When it comes down to size, it makes no sense to have one custom made for $300 or so and have it be less than an inch wider and closer to OEM spec when I can have this one for $125 including shipping and no tax. Less than 1" shouldn't be a problem. The one from ACkits was further off in terms of dimensions and I want the condenser to line up as close to original as it can because of the fans and the hoses.

Absolute worst case: out with the PF and in with the OEM serpentine, which I was VERY happy with before!

[kings1527]

Hey Andrew 4194,

Thanks for the followup. I did end up installing a parallel flow condenser and the results have been great. I've been waiting for some really hot temps to come around so I can get a real good idea as to performance, but as it stands with an ambient of about low 70's, I was getting 36-37 degrees at the center vent. It wasn't an incredibly demanding ambient but I do think the performance was better when compared to the OEM serpentine. I used my AC while driving into work today and it was probably mid to high 70's and I was easily getting the same temps at the center vent.

As time goes on, I'll do more accurate ambient and vent temps and perform back. The install went well even though the universal condenser I used is a bit smaller than the OEM. It's only when you stoop down to take a look through the front grill that you realize it. I'll make an amendment to my blog post on my AC work and add all of this info soon. I'll report back periodically in the meantime regarding what I find with it and then I'll update my blog. Here are some pics of the install:

2835628355

I had to make some spacers for the install and I used some steel ones that I found at Lowe's. The other pic is the final mount to the radiator.

2835828357

One side, you can see the gap from the imperfect fit. And on the other side you can see how it fits flush like the OEM near the hoses. It has to be this way, otherwise the hoses won't connect due to length. And I was unsure if the R12 charge amount would change due to the reduced condenser size. I stopped filling 1/2 lb short of a full charge and performance was so-so. That extra 1/2 lb taking it to a full 2.2 lbs was definitely key.

Overall, great addition. Just give me a bit of time to do some semi-scientific fact gathering on it. And FWIW, I understand Houston is developing a PF condenser with OEM size and mounts. IMO, if you can wait, I'd go with that. I was told that that's really close to being released; within weeks. But for a condenser that's about $65, mine isn't a bad option at all.

[Andrew]

Thanks for the info! Is that the 12 x 27 economy unit from AC Kits.com?

Those are great results...36 to 37 degrees is about the best you can get out of automotive A/C, anything colder will freeze the evaporator coil.



An
Hey Andrew 4194,

Thanks for the followup. I did end up installing a parallel flow condenser and the results have been great. I've been waiting for some really hot temps to come around so I can get a real good idea as to performance, but as it stands with an ambient of about low 70's, I was getting 36-37 degrees at the center vent. It wasn't an incredibly demanding ambient but I do think the performance was better when compared to the OEM serpentine. I used my AC while driving into work today and it was probably mid to high 70's and I was easily getting the same temps at the center vent.

As time goes on, I'll do more accurate ambient and vent temps and perform back. The install went well even though the universal condenser I used is a bit smaller than the OEM. It's only when you stoop down to take a look through the front grill that you realize it. I'll make an amendment to my blog post on my AC work and add all of this info soon. I'll report back periodically in the meantime regarding what I find with it and then I'll update my blog. Here are some pics of the install:

2835628355

I had to make some spacers for the install and I used some steel ones that I found at Lowe's. The other pic is the final mount to the radiator.

2835828357

One side, you can see the gap from the imperfect fit. And on the other side you can see how it fits flush like the OEM near the hoses. It has to be this way, otherwise the hoses won't connect due to length. And I was unsure if the R12 charge amount would change due to the reduced condenser size. I stopped filling 1/2 lb short of a full charge and performance was so-so. That extra 1/2 lb taking it to a full 2.2 lbs was definitely key.

Overall, great addition. Just give me a bit of time to do some semi-scientific fact gathering on it. And FWIW, I understand Houston is developing a PF condenser with OEM size and mounts. IMO, if you can wait, I'd go with that. I was told that that's really close to being released; within weeks. But for a condenser that's about $65, mine isn't a bad option at all.

[kings1527]

Thanks for the info! Is that the 12 x 27 economy unit from AC Kits.com?

Those are great results...36 to 37 degrees is about the best you can get out of automotive A/C, anything colder will freeze the evaporator coil.



An

Yes, I'm real happy with the temps. The real test will be to see how it performs in extreme weather. I'm hoping that due to the reduced head pressure with a parallel flow, it'll be easier for the system to achieve lower temps. For example, a stock system should get around 40-44 discharge temp with an ambient of 110 degrees (per the shop manual) and I'm hoping the parallel flow keeps things in the high 30's with the same ambient. It's all about the ability to exchange heat and a PF condenser is the best at it.

The one I went with is here: http://www.acsource.com/highefficiencypflowcondenser12x2734.aspx

But the exact same one (at about $40 less) is here: http://www.ackits.com/merchant.mvc?Screen=PROD&Store_Code=01&Product_Code=CN20010XC&Category_Code=

I couldn't find a vendor that has the exact same size as the OEM condenser but like I mentioned, it looks like we'll soon have one through Houston and that's a good thing.

[82DMC12]

Hi Kings, my car needs the AC updated desperately. Its to the point I don't drive my car anymore. I already have a new R134 compressor, hoses, orifice, everything. It just needs to be installed on some cool Saturday morning. I want to upgrade the condenser at the same time.

Looks like the one you bought is a bit too small. Is there another model that would have been equal to the OEM size? I'm trying to follow along but a couple of the links aren't working anymore.

Thanks

Sent from my DROID RAZR HD using Tapatalk

[kings1527]

Hi Kings, my car needs the AC updated desperately. Its to the point I don't drive my car anymore. I already have a new R134 compressor, hoses, orifice, everything. It just needs to be installed on some cool Saturday morning. I want to upgrade the condenser at the same time.

Looks like the one you bought is a bit too small. Is there another model that would have been equal to the OEM size? I'm trying to follow along but a couple of the links aren't working anymore.

Thanks

Sent from my DROID RAZR HD using Tapatalk

Hey there,

Yeah, the one I bought was too small but there was no manufacturer out there that has an exact OEM size. Like I mentioned before, I believe Houston is working on a parallel flow OEM sized condenser but it's not available yet (I was told real soon). So while mine isn't an exact fit, keep in mind that I'm getting 36-37 degrees out of the center vents. Not bad. There seems to be more than adequate airflow over the condenser and parallel flow has better performance overall.

The ACkits link from my previous post is bad but here's another one that I just found on ACkits:

http://www.ackits.com/parallel-flow-condensers-non-painted?product_id=31663

It's probably going to be the same fit as mine but it's non-painted and probably a better quality aluminum. I'd go with that one from what I've found out. You could also go with the one that I did and slightly modified to get it to fit just right. I'll try to update my blog in a couple days regarding the whole install.

Regardless, if you're doing a conversion to 134a you'll be much better off putting a parallel flow condenser in there. Serpentine design was outstanding, particularly for R12. But r134a definitely needs the increased surface area for heat transfer to get the best performance.

You're in the same boat as I was: I can't wait wait for the Houston unit because it's way too hot right now. But I think in due time, that'd be the best way to go. Especially with installation as being drop-in, if I'd have to anticipate. It doesn't get much simpler than tightening four nuts on the OEM design.

Once you get all the parts, you could do everything in a day provided you don't run into problems with any of the connections or the orifice tube. Sometimes the connections at the accumulator are a pain because they catch a lot of condensation during usage that causes rust.

Good luck!

[82DMC12]

Thanks, ironically i have already done the exact same total overhaul on a different DeLorean I restored for someone else a couple years ago except I didnt do the condensor. So I know what is involved.

Do you have to remove the radiator to replace the condensor or can you get in there otherwise?

[kings1527]

Thanks, ironically i have already done the exact same total overhaul on a different DeLorean I restored for someone else a couple years ago except I didnt do the condensor. So I know what is involved.

Do you have to remove the radiator to replace the condensor or can you get in there otherwise?

I removed the entire radiator to do the install. With an OEM setup, you might be able to do it without removing the radiator but it'd be impossible when installing the universal condenser. And as much time as it would take finagling everything with the radiator in the car, it'd save you so much time to just take it out.