Parallel Flow Condenser

[dmjlambert]

Here are my facts:
R12 is $25 to $35 per can on craigslist when it is available. By the time I drive across the county for an average pick up of a can of it, consider the total cost to be $40.

Here is my question:
Is there a certain price point at which using R134A is better? Or is R12 worth buying even if it goes to $50 per can? Is the case of 12 cans I see listed right now for $300 something you guys would recommend I run over and get right now?

Rambling:
I would like to have an A/C that works fine when it is 110 degrees outside and high humidity. In my 1969 CST/10 have a stock 350 engine with A/C cab and original A/C in poor condition, so I would like to refresh the system. I have a stock clutch fan. Engine cooling performs fine under all conditions, stop and go traffic, hot outside, or whatever.

From what I have seen on the web including this site, my research tells me using a parallel flow condenser is of upmost importance if using R134A. My wife's modern car uses R134A and the A/C blows so cold even if it is hotter than hell outside, I can't run it on the max cold position without wearing a jacket or rolling down a window. So I would like to think that is achievable in my truck. I'm thinking the thing that would prevent me from achieving that is a regular condenser. I don't want to end up with crappy air since I'm getting ready to spend big bucks on this.

More questions:
Does anybody know of year/make/model of car or truck for which a brand new condenser can be ordered from a parts store, and which is parallel flow and which will fit in our trucks? And the maker of any adapter tubes with fittings that will adapt, perhaps fabricator who is familiar with these trucks and what it takes to get superior A/C working?
Does anybody know if Vintage Air or Old Air or any of those full kit makers actually has a parallel flow condenser as part of their kit?

[68c10airstream]

I will sometime get around to finishing my ls 5.3 ac system. It will be basically a trailblazer ss 6.0 ls compressor/lines/condenser and make it adapt to a stock ac box. The condenser in my hands fits nicely in the opening. You would need to adapt/tig weld the ends to match what you have. I figured that the trailblazer interior volume was more than our truck cab so it should be ok. I'm using the stock 5.3 clutch fan and a 68 fan shroud.

Why use a trailblazer compressor? Because the suction/discharge ports on the compressor are positioned front to back and i won't need to notch my frame for the lines.

With your system switched to r134 your poa valve i believe will need to be adjusted/replaced to work right, but someone will chime in that has been there and done it, or search for r134 poa valve articles. Good luck!!

[lutronjim]

There is a refrigerant that is called FR12 that works in a R12 system that's much cheaper

[Greasey Harley]

Don't know about retrofit but, an original r12 system in good working order should be plenty cool in a regular cab truck. Our C30 shop truck will just about grow icicles if you let it run long enough.
We replaced the o-rings and soft lines with repops from lmc, poured some oil in it, e-vacc-ed the system down to 300 microns and put the recommended charge ( 2.75 lbs I think) back into the system. It blows COLD.


It is crucial that you pull vacuum on the system before you charge it.
You might reach out to your local hvac guy and see if you can get him to top you off with "Hot-shot" , that stuff works great in R12 systems.

[brown7373]

I spoke with Classic Auto Air last week, and they do not sell a parallel flow condenser for our trucks...although there is talk about making one. If anyone knows if someone else makes them, I'd be all ears. I have one in a 72 Cutlass Convertible and a 70 Bonneville Convertible and both blow 30 degree from the vents, using 134a,with real recalibrated POA and all other components in good working order. Using and recalibrating a POA in my 72 truck helped a lot, but not as good as the cars with parallel flow.

[bMr]

Originally Posted by dmjlambert

Here are my facts:
R12 is $25 to $35 per can on craigslist when it is available. By the time I drive across the county for an average pick up of a can of it, consider the total cost to be $40.

Here is my question:
Is there a certain price point at which using R134A is better? Or is R12 worth buying even if it goes to $50 per can? Is the case of 12 cans I see listed right now for $300 something you guys would recommend I run over and get right now?

Rambling:
I would like to have an A/C that works fine when it is 110 degrees outside and high humidity. In my 1969 CST/10 have a stock 350 engine with A/C cab and original A/C in poor condition, so I would like to refresh the system. I have a stock clutch fan. Engine cooling performs fine under all conditions, stop and go traffic, hot outside, or whatever.

From what I have seen on the web including this site, my research tells me using a parallel flow condenser is of upmost importance if using R134A. My wife's modern car uses R134A and the A/C blows so cold even if it is hotter than hell outside, I can't run it on the max cold position without wearing a jacket or rolling down a window. So I would like to think that is achievable in my truck. I'm thinking the thing that would prevent me from achieving that is a regular condenser. I don't want to end up with crappy air since I'm getting ready to spend big bucks on this.

More questions:
Does anybody know of year/make/model of car or truck for which a brand new condenser can be ordered from a parts store, and which is parallel flow and which will fit in our trucks? And the maker of any adapter tubes with fittings that will adapt, perhaps fabricator who is familiar with these trucks and what it takes to get superior A/C working?
Does anybody know if Vintage Air or Old Air or any of those full kit makers actually has a parallel flow condenser as part of their kit?

After similar deliberations for many months I'm in the middle of the swap to R134. I didn't want to spend a lot of money buying R12 only for it to escape to the atmosphere should there be a leak. And seeing as the front seal of the compressor is a known weak point, if I was going to be in for a compressor I might as well make the swap while I'm at it.

There are several great threads on here about the 134 swap, condensers, POA valve adjustment, etc.; many of those threads benefit from the input of board member FAA Benny.

For me the biggest decision wasn't whether to swap from R12 but whether to switch to a new system from Old Air, Vintage Air or the like. I did not want to spend the $500+ buying hoses, a compressor, a condenser, and misc parts and refrigerant and still be be hampered by 45+ year old diverter flaps, cranky vacuum actuators, and the like. Had my diverter box or control head needed replacing or refurbishing, I probably would've swapped to a new system.

To your point about the condenser, as of July 2018 no one sells a bolt-in parallel flow condenser to work with the factory hard line locations. However, there are a plethora of modestly priced parallel flow condensers available on eBay or through other vendors, and Vintage Air manufactures hard lines with the requisite o-ring connections in various lengths that you can then bend yourself. (Local parts stores rent tubing benders.)

For sizing a new condenser, the space available is about 31"w by 15"t. There are two stampings on the radiator/header panel which limit width, and the hood latch assembly is the limiting factor on height.

[A1971Blazer]

I'm in the middle of this same project right now....My '72 K/5 is missing some pieces and I sourced an entire under hood unit for $100.00....

The PO had completely reconditioned the entire under dash assembly already so it's ready to go.......

It's funny about the price.....I had one old can of r12 in my cabinet....price tag still on it.....97¢....

I found 4 cans locally for $20.00 and 4 cans that I had shipped to me for $20.00+ shipping...

I'm planning on trying to get it working with the r12 charge....stay tuned...

[72c20customcamper]

I have 2 20lb tanks of r12. I bought it cheap from the supply house just before they banned the sale of it. 3 of my cars use it. But so far none of them leak as of now.

[demian5]

There is one through Classic through Original Air...

https://originalair.com/67-72-chevro...t-134a-stage-2

[davepl]

???

I have a parallel flow condenser. New lines. But the old compressor leaked, so new aluminum compressor painted black to look stock, and it blows cold and works great and has lasted for years with R134

Overheats in traffic with the AC on, that's how well it works :-)

[Andy4639]

Ok all this talk about R-12 and 134 A is like Chevy vs Ford. Both do the job well. Both have the same things bad about them but if both systems are working right they will blow 30* air at the vents.

My 71 C 10 has had mods done by me and it blows 30* no matter what and it's been in operation for years. Yes it has the factory basic system inside the cab but the out side is all newer stuff.

I went with Classic air stuff along with late model Chevy truck stuff and the hose connections are like anything else just buy what you need. I bought Classic air kit with all the fittings, compressor, condenser and put it all together had the lines made up and it works great.

These are the old 305 TPI setup.





The 6.0 with same setup.




In my 64 SS Impala I used everything in the car when I bought it which per the owner at the time had been swapped out. I put new lines and drier in it with 134a and it blows 32* all day long. I'm running the older A-6 compressor in the car also. See how the lines are curled up. I took it all a part and had longer lines made and hid them inside the fender to clean that side up.

[leddzepp]

It’s simple: Use whatever gas the system components are designed for. Mixing and matching components to save a few bucks to run r134 will just lead to headaches frustration and a poorly functioning AC. Both of my factory AC systems run r12, blow snowballs in 110 degree heat and have worked for years with no issues. Prior to that I chased my tail trying r134 in it. All my newer vehicles run r134 and blow snow too...because that’s what they are designed for.

[Big Kev-O]

"they will blow 30* air at the vents"

For the record your cars AC should blow air around 40-42 degrees. IF your vents are putting out 30* air your refrigerant charge is not correct, or you have a broken thermometer. When an AC evaporator is under 32* it begins to freeze the moisture in the air and turn your evaporator into a huge ice block which prevents air from flowing across the coil. You also risk slugging the compressor with liquid.

You should not try and attempt to charge your system to achieve 30* air out of the vents.

[Rufas]

Originally Posted by Big Kev-O

"they will blow 30* air at the vents"

For the record your cars AC should blow air around 40-42 degrees. IF your vents are putting out 30* air your refrigerant charge is not correct, or you have a broken thermometer. When an AC evaporator is under 32* it begins to freeze the moisture in the air and turn your evaporator into a huge ice block which prevents air from flowing across the coil. You also risk slugging the compressor with liquid.

You should not try and attempt to charge your system to achieve 30* air out of the vents.

[dmjlambert]

Thanks everybody for input so far.

Originally Posted by davepl

???

I have a parallel flow condenser. New lines. But the old compressor leaked, so new aluminum compressor painted black to look stock, and it blows cold and works great and has lasted for years with R134

Overheats in traffic with the AC on, that's how well it works :-)

OK, if I want to get going like that, what parallel flow condenser do I buy? What do you mean about overheats in traffic, do you mean your engine overheats and you think it is related to your AC?

Originally Posted by demian5

There is one through Classic through Original Air...

https://originalair.com/67-72-chevro...t-134a-stage-2

Any experience with that kit? I probably can't use it anyway because I don't have a long water pump.

Originally Posted by Andy4639

...and put it all together had the lines made up and it works great.

What sort of place do you go to have the lines made up?

Originally Posted by Big Kev-O

"they will blow 30* air at the vents"
... When an AC evaporator is under 32* it begins to freeze the moisture in the air and turn your evaporator into a huge ice block which prevents air from flowing across the coil. You also risk slugging the compressor with liquid.

Yes, I guess I should have said I would like the A/C to work for long trips as well, not just for show or short trips.

Originally Posted by bMr

After similar deliberations for many months I'm in the middle of the swap to R134. I didn't want to spend a lot of money buying R12 only for it to escape to the atmosphere should there be a leak. And seeing as the front seal of the compressor is a known weak point, if I was going to be in for a compressor I might as well make the swap while I'm at it.

There are several great threads on here about the 134 swap, condensers, POA valve adjustment, etc.; many of those threads benefit from the input of board member FAA Benny.

For me the biggest decision wasn't whether to swap from R12 but whether to switch to a new system from Old Air, Vintage Air or the like. I did not want to spend the $500+ buying hoses, a compressor, a condenser, and misc parts and refrigerant and still be be hampered by 45+ year old diverter flaps, cranky vacuum actuators, and the like. Had my diverter box or control head needed replacing or refurbishing, I probably would've swapped to a new system.

To your point about the condenser, as of July 2018 no one sells a bolt-in parallel flow condenser to work with the factory hard line locations. However, there are a plethora of modestly priced parallel flow condensers available on eBay or through other vendors, and Vintage Air manufactures hard lines with the requisite o-ring connections in various lengths that you can then bend yourself. (Local parts stores rent tubing benders.)

For sizing a new condenser, the space available is about 31"w by 15"t. There are two stampings on the radiator/header panel which limit width, and the hood latch assembly is the limiting factor on height.

This is interesting info. I don't have actuators and flaps that work properly, but I have not sufficiently explored them to see if I can fix. I don't know how to pick among the condensers from eBay or other sites, and make sure I end up with something I can use. Getting the Vintage Air hard lines in a length I like and with the fittings I need and bending to shape sounds interesting. I have a tubing bender. The thing that would worry me is figuring out what that connector name and size is that is on the truck and that is on the condenser that arrives, and figure out if it is metric or standard, and any other decisions I would need to make to keep from ordering something that just doesn't work out.

For the R12 crowd who have massive quantities stockpiled:
I imagine by the time I replace a part or two, test the system, and then charge it up with a couple hundred dollars worth of R12, it would make me feel pretty bad to watch and hear that spring a leak a year later and spew money into the air, then repeat when the R12 is $400. I have a 49 year old system here and if I'm going to replace every part to increase the chances of me going for several years without failure and re-purchase of R12, I might as well not buy an all-new R12 system. By the way, I have also noticed old R12 cans I usually see are only 1/2 full after so many years of laying around and getting rusty. These are the things that make it a difficult decision. For those of you who have stockpiled since you were young and have no worries about future cost, that's great.

[Andy4639]

Originally Posted by Big Kev-O

"they will blow 30* air at the vents"

For the record your cars AC should blow air around 40-42 degrees. IF your vents are putting out 30* air your refrigerant charge is not correct, or you have a broken thermometer. When an AC evaporator is under 32* it begins to freeze the moisture in the air and turn your evaporator into a huge ice block which prevents air from flowing across the coil. You also risk slugging the compressor with liquid.

You should not try and attempt to charge your system to achieve 30* air out of the vents.

Sorry yes 42* I was at work and didn't have time to go back and check my spelling, sorry 40* is correct on both vehicles.

[bMr]

Originally Posted by dmjlambert

This is interesting info. I don't have actuators and flaps that work properly, but I have not sufficiently explored them to see if I can fix.

The proverbial slippery slope! LOL, been there and done that.

If it were me, I'd put together a rough estimate of replacing/repairing the in-cab components and then an estimate of each option: recharging R12, swapping underhood components to R134, and buying a complete kit to replace underhood and in-cab components. At least then you'll know how much you're likely to be in for.

[1972RedNeck]

Duracool, or a homemade copy of it will cool as good as R12, and better than R134. It is a mix of propane and isobutane. Flash point is actually higher than r134A.

Best part is that you can mix your own. One 8 oz can of isobutane (mountain stove fuel), and 12 oz of Coleman propane (found to be drier than most). Takes about half the weight as the freon charge.

[dmjlambert]

After reading more, I am even more lost. I am frustrated because I have no place to walk into an look at the parts or a complete system, and I'm a visual learner. Let's just say I'm taking my truck and tools and moving to a desert island. I will have no chance of ordering any parts after I get there. So unless I can fabricate parts out of coconuts I need to order all I need now. Let's say my truck has been stripped of the A/C related stuff, condenser, compressor, hoses, evaporator and evaporator box, heater core and box, blower motor and fan, all inside ducts and diverters, outlets and outlet hoses, vacuum-operated flaps, control panel, and whatever else is part of the A/C system in the cab and in the engine compartment.

If I order an Old Air system or Vintage Air, or whatever kit I should get to install a R134a system, what do I need in addition to that kit? I have a 350 engine with short water pump and v-belt drive system and the holes in the cab firewall and dash are for a factory A/C equipped truck.

[dmjlambert]

Here's a kit, I have no idea what brand. I suppose I am concerned about getting replacement parts in case any part of it breaks. It is possible to tell from this picture if this is a parallel flow condenser? The description is not detailed.
http://www.classictruck.com/product/...roster_HAC-236

[dmjlambert]

Here's the condenser Classic Industries sells. In their paper catalog, which I received today, it says 1967-72 "all refrigerants." But I don't know if it is parallel flow.

https://www.classicindustries.com/pr...s/ap72011.html

[RichardJ]

NO.
The first thing you will notice about a parallel flow is the large round tanks on both ends. The second is that the horizontal tubes are flat instead of the old style round tubes. The side tanks are chambered so that the refrigerant flows horizontally in 3 or 4 lines, then drops down and flows back in the next group of lines.

[RichardJ]

I couldn't find what you are looking for on the Vintage Air web site, but found this on Jegs.

Note that it says it is a representative image. The price includes dryer and other hardware.

Call Vintage Air and be clear about what you are looking for. Their image appears to show a parallel flow.

[oldgold70c10]

My '78 was converted to R134A by the previous owner in 2007. It still has the original condenser, evaporator, and new compressor and receiver. On the highway I have to turn the fan down because it will get so cold on high. In city driving, it is not as cold, but I never need to roll the windows down or break into a sweat.
I think the only difference between this setup and the 67-72 is the metering device method and there is no low-side thermostat cycling switch.

[dmjlambert]

Originally Posted by RichardJ

NO.
The first thing you will notice about a parallel flow is the large round tanks on both ends. The second is that the horizontal tubes are flat instead of the old style round tubes. The side tanks are chambered so that the refrigerant flows horizontally in 3 or 4 lines, then drops down and flows back in the next group of lines.

Thanks for that picture and description, that helps. The picture of the condenser with A and B dimensions is interesting. Is it from a vendor who will sell me a condenser if I just specify the A and B dimensions? If so, perhaps brackets that I would need to fit the truck could be added or clamps fabricated.

Regarding the Jegs listing for the Vintage Air condenser, is -6AN and -8AN fittings what connects to the existing factory setup, or would I need to get some sort of adapters or tubes made? That looks like a good find, I will give them a call at Vintage Air and ask more about it.