Yes please! And time your refill run time.
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alright all that is interested. i have to make some corrections to my previous post it isn’t all my fault the squirrels in my head mess with my typing. as if you all can’t tell 
. do forgive me grammar isnt my strong hold so bear with me. so i will just make a post with the corrected info and new data.
alright my compressor is a 7.5 hp two stage i had installed a aftercooler between the take and compressor head. i replaced my compressor 4 years ago due to a failed bearing and then the motor 2 year ago no mods at that point.
the original compressor had 5/8 output i modified to 3/4 due to available fittings new and old compressor was slightly different. i also went from a 5 inch pulley down to a 4 on the motor.
so to the data with the after cooler it took 4 minutes to recharge my tanks of 140 gallon i had said 3 earlier i wasn’t using a stop watch just looked at time that one is my fault sorry to mislead. my compressor head got up to 320 degrees which i figure was ok due to the fact a google search said 300 to 400 degrees was normal. i also put a tach on the motor it was a steady 3450. with this set up the after cooler i bought had 5/8 fittings which i was happy with due to that was oem size. i did notice a small amount of blow by with the miles i didn’t mind.
now the unfair comparison comes from for me to bypass the aftercooler the cheapest way to do that was to stay with the 3/4 pipe i know this will make a difference for sure i just didn’t want to spend more money.
so with the after cooler gone the rpm stayed 3450 no change between the two. the compressor temp went from 320 to 250 degrees. i let the compressor head cool to about 150 ran it again temp went up to 265. the cycle time with the after cooler gone went from 4 minutes to 2. i didn’t seem to notice a difference in the amount of blow by. i know it is a unfair comparison but it is data. hope it will help someone.
so as a whole i will not waist my time putting the after cooler back in the loop. if i see a difference post tank i may team it up the other one later.
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That is interesting how my 248 temp matches your 250. Cool…or I mean neat!
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@Phillipw to what psi? I’m liking the data that you’re posting.
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my compressor is stock i have never changed the points to reduce the pressure i know it doesnt need to be that high it is at 175 after main tank i have it turned down to around 125. so that is 80 gallon at 175 and 60 plus lines at 125.
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Geez 175psi that’s high. Save some life of your compressor and back it down to at least 150psi. I have mine set to cut out at 140psi.
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That is oem setting. my compressor has a 175 psi rating. The first compressor lasted well over 20 years. Had a bearing failure while I was out of town is the only reason it isn’t running now.
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It would be really interesting to see that test again with a clamp on ammeter showing how much the current the motor is drawing in each case.
A big factor about compressing air is how much it costs to make it.
Running your system at the lowest possible operating pressure will make it the most efficient power wise.
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I agree that would have been a good idea. I will not promise anything if I get time in the next little bit I may hook it back up and check it. With the change in seasons time is really getting hectic. I did this change knowing that it would make a difference.
The after cooler is a neat idea which I did not putting a lot of thought into it. You can’t keep all the moisture out of your tank so it isn’t really needed. It did reduce air temps near 200 degrees but it dropped 70 just removing the cooler.
Now when I do long runs I need to make sure my post tank cooler is doing a good enough job.
We live and learn. A mistake isn’t a bad mistake as long as you learn from it.
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I can confirm now with my aftercooler removed I’m getting some water in the tank when i drain it. So the mystery of where did the water go is solved. Not seeing any difference in my desiccant consumption yet though. It’s still not warming up where I am.
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@brownfox So what kind of difference was there in your cycle time?
What area do you live in? Here in va seems even in the winter I catch massive amounts of moisture.
@TinWhisperer has been the curiosity that killed the cat. I plan the check the amperage draw on my motor. He had to ask!!
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This points out the value of consistently draining the compressor tank on a regular basis. That is what was saving my bacon before my recent installation of all the drying apparatus, I just didn’t know it.
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You will see lots of smaller compressors with very high cut in and cut out setting as this make it seem like it has more capacity. For instance if you have a cheaper air impact wench one way to get more Power turn up the air.
Having a lower set points helps lots of things, more efficient, less heat, easier on motor and pump.
It does take some getting use to with lower pressure, unless you have all of your lines on regulated air.
My cut out/off pressure is 125 and right after it shuts off, if I use a blow gun on a unregulated line its almost to much.
Please keep in mind I am old and almost everthing is too much for me
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I can’t consider my compressor small it is a standard 80 gallon compressor. I actually seen two different brands yesterday that advertise 175 max pressure. To be honest I am going off memory. I know it is 
bad. I have to change pressure gauge to get a accurate reading. I do for a fact know it is well over 150.
There is actually some really good reads on the internet about efficiency gain and loss with changing compressor pressure. There is also good reads about cfm gain and loss as well.
Yeah I ain’t opening that can of worms.
Chicken!
You should time how long it takes for it to go from 0-125 then from 125-175 just for fun
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Ah you know it may mess with a few people’s blood pressure I don’t want the blame. Nah nothing wrong with opinions.
I started to buy a new pressure gauge the other day that is the only way I could do that kind of time trial. All the stores around here either have them gold plated or real proud of them.
From what I read the industry standard is a loss of 1% power efficiency for every 2 pounds above 100 psi. That can be looked at both ways it’s a trade off. Then this one is a hard one to find agreeable so it isn’t my opinion. There is a 1% loss in cfm efficiency for every 1 psi in reduction.
My understanding just for a example if your compressor has 100 cfm at 100 psi. You drop your pressure to to psi you would lose 25 cfm.
I don’t remember the exact cfm on my compressor it is around 15 cfm give or take at 125 I believe. Way above what my plasma needs. I do a lot of blasting where the cfms are a benefit. So it honestly would be a sell off for me to drop my pressure.
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You are giving us all great data. Don’t stop now. What happened to us wanting you to “take one for the team!?” But I agree: No need to have “rapid unscheduled disassembly.”
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I’m in Utah. I don’t remember the refill time with the cooler attached.
At this point I’m definitely not installing the new one I bought. But now I’m curious, what kind of cooler did you have on yours? The derale one most use or something else? The derale has somewhat decent sized tubing.
It was a different one. Most of the derale had 1/2 inch fittings my was 5/8 I don’t remember the brand without looking. I am going to throw mine back on this weekend to see the amp draw. Plan on using it for a spare post tank cooler.
I was like you and did not want to mess with my pressure as I thought if I went from 160 down to 125 there is no way that would work for me. Until I tried it.