This may be the the compression fitting @TinWhisperer is referencing.
Not sure about the o-ring end. You might replace the oring all together. Maybe put a nipple and adapt from there.
I went to a race shop and had them make me a flexable hose (break line) to connetct to a fitting from the compressor to the derale AN8 fitting. I ran copper tube from the water separator to the tank and used the same compression fitting from mcmaster carr
Do you have a refrigerated air dryer as well
No, I don’t I drain compressor tank 3-4 times throughout the day. don’t get much water from tank when I drain.
Is that a significant leak?
That sounds like a significant leak. Did you just test the loop itself or compressor and cooler as one? If all together then might jot be that bad but seems to be significant. Was your compressor holding pressure before you added the cooler?
You need to take some soapy water and spray down all your pipe joints and fittings.
Did you find the fittings you needed? If not, look at a company called Evil Energy selling on Amazon. I got most of my fittings from them, and specifically one attach to the Derale cooler(8AN fitting). They have fittings that connect 8AN to 1/2" and 3/8" NPT.
Example of one I used:
Amazon.com: EVIL ENERGY 8AN Female to 3/8 NPT Male Swivel Adapter Fitting Aluminum : Automotive
my set-up…
cool dry air…
I dont understand all the people on here that have shops with absolutely no dirt in them, how is that possible?
Man, that looks like a great setup. The floor space savings is a great benefit.
I was just wondering, did you relocate the original bottom drains on the tanks?
I’m sure @toolboy will chime in, but it looks like both tanks and the refrigerated dryer are all plumbed into that white pipe running horizontal under the system, my guess is that’s a common drain line.
You’re probably right. I thought that was the air going over to the copper tubing, but it probably is the drains.
I go my copper all soldered up last night. Saturday I should get it hung. Yeah!
yes I relocated the drains to what used to be the side drain…works fine
yup…I did all my pressure pipe in copper soldered or threaded with pipe dope…
the white pex goes from the drain lines on my copper cooler and passes by the tank drains and the refrigerated cooler…and now goes all the way to the sink in my shop…
due to the pex pipe…location of the sink I hardly hear the blow out of the units…
Nice set-up. I am inspired.
That is really clean looking man. Great work. Mine is looking pretty homely because I used all scrap wood and metal. I will make it look a little better when I’m sure I like the setup but,…I’m cheap, so not much better. 
I love your horizontal, elevated tank approach. I may get ambitious and give that a go this Spring.
I fired mine up for the first time since completion yesterday. I may go ahead and move the water trap/regulator down fully below the AT cooler. Its about mid-level now. I wanted to try it up to minimize accidental hits and such so I mounted it up at that point. But as feared, I think water may be ponding in the bottom of the cooler. I definitely had some slowing of the compressor speed as it exceeded 100psi and up to 120 psi shutoff point, possibly back pressure. Motor temp stayed okay but I only ran one cycle.
I’m going to run it again today and slightly open the exit port connection on the cooler and see if any water comes out and/or if the compressor speed changes.
If I move the trap and still has back pressure, I am going to move the cooler to after tank. I am curious to see which way works best anyway.
On the up side it was 47F in the garage and the cooler in entry port temp = 185F, cooler out at exit port = 67F.
Not a good pic. A friend wanted to see the copper loop. But upper left of pic you can see my water trap is about even with center of the cooler. I can easily drop it down below bottom outlet.
So been reading and looking at possibly making home made desiccant dryer and like the size of the water filters but durability has me concerned. Found sch 80 clear PVC pipe that is rated to 190 psi and works with regular PVC fittings and glue so this might be a safe alternative to water filters.
Read the finer print in this PDF. See if you can find the red flags I found.
@TinWhisperer between the temp derate and also saying not to use for compressed air i suspect that is the red flags. Still higher rated than water filter housing though.
I ended up moving my cooler to post tank. All the evidence for the slowing of my compressor pointed to increased back pressure.
Definitely back to normal operating speed. I haven’t measured temp impact yet because I haven’t rewired the fan motor. Need to decide strategy: run fan all the time I am cutting; tie into trigger signal and send to relay to operate fan.
