Compressor turns off at 80PSI

We are new to pneumatics and are having trouble with our air compressor stop pumping air into the tanks at 80 psi. We do not know if this is something that you program or if it is a fault in the pressure sensor. Is it a physical adjustment on the pressure switch? Do we need to somehow calibrate the pressure sensor.


Likely a bad pressure switch. Replace it.

Replace the pressure switch. We ordered a bunch of them a couple years back and tested all of them to get as close to 120 as we could. We had a couple that only would get us to 105, the rest ran between 113 and 118.

The Nason pressure switch is not meant to be adjustable by end users. That should only be done by the factory. So like the other posters said, the most likely problem is a bad pressure switch.

However, since you said you are new to pneumatics, I will put forth three alternate possibilities. One is that the pressure gauge you are using is faulty, try switching it with your other pressure gauge. Second is that you are accidentally reading the pressure gauge after the pressure regulator. You use the wording “compressor stop pumping air into the tanks at 80,” so third, if you mean the compressor keeps running but you no long gain air, then your regulator is in the wrong way.(very common, but doesn’t sound like your problem)

I felt you should have a broader troubleshooting path forward, since you said you were new to this. Please understand, without seeing your setup it is hard to give definitive diagnosis, so you may have done everything right and it is just a bad switch.

Others have given good advice, but I’ll add one thing – R82 limits modifications of pneumantic components. Note that the pressure switch is not part of any of the allowed modifications.

I will second the suggestion to make sure you have everything plumbed properly, and that you are reading the gauges correctly (that is, that you have a gauge connected before the regulator, and one after, and that your high side pressure is really only 80 psi)

The regulator plumbing can be confusing. There are 4 ports on it, one is input, three are output, and the output arrow will tell you which side is which. Unless you are using a different regulator than I’m familiar with.

Pictures will be a huge help for all of us, to help you.

Even the arrow can be confusing. It points away from the input not towards the output.

…As I pointed out to one of my students a couple days ago…

We have switched the pressure switch and it solved our problem! Thanks.