Compressor Aftercooler

Spend so much time figuring out if I could never stop to think if i should lol, Aftercooler setup came out nice, have to add one supper to the upper copper run as it shakes when running and don’t want it to stress crack the line or after cooler inlet. Made a larger loop to see if it would help dissipate more heat, might look for some fins to add on to it. But like the setup, added hour meter to track compressor run time, fan turns on as soon as compressor turns on and fan runs for 1 min after motor stops.


Where did you get the aftercooler fan control and timer unit?

I build it, Electrician by trade and geek for control work. Sourced pretty much everything off amazon and the face plate i designed and had cut / engraved from Front Panel Designer, they have a free software that you can design aluminum panels and then send to them to cut / engrave.
Used CT to monitor compressor running, Led indicator lights, Off delay timer set to 1 min to keep fan running for 1 min after compressor stops, and a 120v to 12VDC power supply to power fan all in a PVC electrical junction box.

I have the same setup you are using, just not the control box and I thought that really cleaned everything up and looks really professional, you did a fantastic job. Now you mentioned a CT, im not sure what that is? Also did you make a wiring diagram for all of this or did you make it up as you went?

Thank you,

I do have a wiring diagram at work I made to plan it out I’ll take a picture tomorrow. I used a CT (current transformer) with build in relay. The wire passed thru it so when it detects current from motor of compressor it closes relay and turns on fan. I went this route to a voice running extra wires to motor side of pressure switch due to how small and tight the pressure switch compartment is.
Once the CT relay sees the draw of the motor it closes its contacts and energizes the off delay timer. This timer starts fan immediately, but when the compressor stops and opens the contact, it leaves the fan on for a preset amount of time it is adjustable. I said it to 60 seconds just to try to cool the radiator down a bit.


That would be great! Thank you so much! Could you also share the amazon links of the led lights, switch, and timer? I would really appreciate it. Also just out of curiosity, have you measured the copper line temperatures before the aftercooler and after the aftercooler to see how much of a temperature change you have?

Yes i will put everything together tomorrow when i get to the office,
I have not check with temp gun yet, in final steps to finish XR table assembly and should be off and running, i filled tank from 0psi and input line was too hot to touch and output was just warm. ill get some temps prob by next weekend, i have alot of air tools and with plasma cutting i figure she will get a work out.

Here is the material list, ill upload wiring diagram after

LED Indicator

3 – Position Switch

CT Relay

Hour Meter


12VDC Power Supply

Off Delay Timer

Face Plate

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Final Aftercooler.dxf (128.1 KB)

This is fantastic, thank you for sharing all of this info with me, I tried to upload the dxf file you shared with me to front panel express but im having an error pull up, did you have that issue when you loaded the dxf on there program?

There is a different file format that it saves and it wouldn’t let me upload it on this form. If you have an email I can email you the file.