Please check my thought process

[derekf]

Please check my thought process as I don't quite know enough to be dangerous, and that's a goal.

My evaporator is from a 2000 Camaro. The ends on the lines look like this (photo from interwebs):



The compressor is the Sanden SD7 that comes with the Holley LS pulley/accessory kit. Lines look like this:


but Holley also makes a kit to adapt those to 3/4-16 UNF and 7/8-14 UNF:



My condensor is Vintage Air's 037033 which has #8/#6 AC fittings.

I swapped email with VA and it did not go well; per their rep, their hose kits would not go well for me and my best bet would be to tear it all out and start over with one of their complete systems (go figure).

My thought is:

From the evaporator to the drier (with orifice tube and trinary switch): stock GM from that same 2000 Camaro. Would bolt right up to those fittings.

Evaporator to condensor - same idea, stock GM - BUT:

The crimp-on ferrules VA sells - like these:





- if I took the stock GM lines and cut the ends that didn't fit my needs off, could I have these sorts of fittings crimped onto the ends of the hose where I needed them? I'd cut one end off the hose from the condensor to evaporator, and then one in the hose from the drier to the compressor. The compressor/condensor hose would be net new since neither end would be GM anyway.

Would this work? Is it a horrible idea (of course it is, but how horrible is it?) Is there a "good" way to finish the AC without tearing it all out and starting over?

[dhutton]

If the original GM hoses are standard size then yes you can crimp fittings onto that hose. Should be 6 hose and 10 or 12 hose. Check for labels on the hose. Or Google the hose dimensions and measure the diameter. The fittings are easy to buy.

This seller is in Bedford and ships fast.

https://www.ebay.com/sch/i.html?_trk...ssn=johnjoysyl

I have a crimper if you want to bring the hoses by to crimp. Or some auto part stores will crimp.

Don

[ULTM8Z]

The SD7 is a great compressor. I have one on my Classic Auto Air system in my 71 Camaro.

Quiet, efficient, etc.

[derekf]

I have assembled my system.

As mentioned:

• stock 4th gen Camaro evaporator, drier, orifice tube, trinary switch.
• 4th gen radiator fans
• Sanden SD7B10 compressor
• Vintage Air 037033 (24"x12") condensor

Weather report says it was 92 degrees out, and chart says I should have 45-55psi on the low side and 250-270psi on the high side. I charged to 40ish low side which was 275 on the high side.

The air coming out of the vents was only ~65 degrees on max. In motion it was pretty much the same so probably not an airflow thing.

The condensor was *hot*.

Am I undersized on the condensor? I'm a bit limited on how big it can go and still get airflow through it - or does it not matter so much if the corners don't get flow?

[ULTM8Z]

Are you sure you evacuated the system properly?

In that weather I can get easily around 40-ish F out the vents.

Same size condenser and Sanden SD7 compressor.

I probably have about 27 oz or so in my Classic Auto Air system. It calls for 24 oz, but the SD7 is higher displacement so I put in a few more ounces. It'll freeze you out of the car on most days.

[dhutton]

When testing and charging a system in my shop I set the idle to 1500 rpm and set a box fan blowing into the grille/condenser. I think this is standard practice.

Don

[derekf]

Are you sure you evacuated the system properly?

Well, I was before you asked; my vacuum can only draw about 25 inches of vacuum; left that running for half an hour, sealed the system for half an hour and verified no leaks. Doesn't seem like there'd be much atmosphere in there percentage-wise even at worst-case.

No idea how much went in. When a can stopped drawing I swapped it out and I was really just watching the gauges. A couple of them were partial cans anyway.

When testing and charging a system in my shop I set the idle to 1500 rpm and set a box fan blowing into the grille/condenser.

Had a 36" fan blowing into it while charging; if it was a compressor speed thing or an airflow thing I'd think driving would have shown that?

When I say the condensor was hot, I mean as in "can't touch it without yanking back the finger".. which is why I was thinking maybe it just didn't have enough surface area to get rid of all the heat.

The condensor is in front of the radiator. I was thinking to go much larger and mount it between the radiator and the fans.

[dhutton]

Putting the condenser between the radiator and fan will mean that it is getting hot air from the radiator. Bad idea, there’s a reason they are always in front of the radiator. How big is the gap between the condenser and radiator?

If the condenser is too hot that could indicate inadequate airflow through the condenser. Post up some pics of your fans and shroud etc.

Fourth gen fans are usually set up as two speed with a series/parallel hookup. Is that how you have it?

Don

[ULTM8Z]

So a couple things...

The evacuation process sounds a bit suspect. IIRC, when I did mine I was able to get at least 29 inHg. Anything less than a hard vacuum allows for residual air and some moisture to be present in the system, which reduces system performance. It may not be a huge difference, but everything adds up.

The other thing is you need to make sure your condenser is very close to and/or sealed to the radiator or radiator support. Otherwise a lot of the air (even when driving at speed) could just go around the condenser, looking for the path of least resistance. The air will not want to go through the restrictive path of a condenser + radiator on its own, so it has to be forced to do so. On mine, for low speed performance, I also put a small aux pusher fan on the front of the condenser as well, and having it hooked up to the ECM allows it to be turned off at 35 mph (which is what I set it to).

My radiator is sealed to the engine side of the radiator support. The condenser is sealed to the other side. Of course when I say "sealed", I don't mean a perfect air tight seal. But a sufficient amount of weatherstripping around each to greatly minimize leakage into and out of that path between the radiator and condenser.

I seriously doubt you need a bigger condenser though. There's simply something off in your setup.

One thing I also did was to insulate my hoses behind the dashboard as well to avoid the air picking up heat as it goes from the evaporator to the vents. Ceramic window tint also helps the car to cool down more quickly as the recirculated air gets colder faster w/ less thermal radiation coming in. Good insulation under the carpet and above the headliner as well.

Just lots of little things to increase thermal efficiency... it all adds up in the end.

Yesterday it was damn near 110F in SoCal and I was still getting very cold air out the vents with the same size compressor and condenser, and yet my coolant temps never got about 200F with a stock-ish aluminum radiator, stock water pump, 180F t-stat, etc... on a ~420 hp 383. It's all about maximizing thermal efficiency.

[srode]

Was the dryer open to the atmosphere for some time or was it sealed and installed quickly? If open to the air for a while the desiccant in it might be saturated.

[Vimes]

On not knowing how much freon you put in, get yourself a small kitchen scale that measures ounces. My wife has one that I use, just slip it into a gallon ziploc and I don't have to worry about contaminating our food with garage. Weigh the can before and after and you will know how much you have even with partial cans. If using one of those can trigger jobs with the foot long hose, make sure to weigh every time with it either attached or not attached. I'd do attached just so you don't have to wonder how much of the last can went in.

[Eurostang]

A hot Condenser is the sign of lack of condenser capacity or possible non-condensables in the system. Depending on the condenser configuration the outlet should not be excessively hot. You can reach out to me if you like. I am a Commercial HVAC designer.