Air Regulator Questions


Lots of folks have compressed air regulator questions. Here are a few that I have received and answered along with a forum link so you can ask your own.

A visitor asks: I have a Craftsman 3 gal. Air Compressor, 1 hp, Horizontal Tank. Just got this compressor and i just wanted to know how do u adjust the regulator gauge? Ii know i turn the knob but i just dont know how to adjust it right, do i loosen it or tighten it, to regulate my air, the manual doesn't tell you how to adjust.

My response along with a shameless plug:

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OK, enough of the shameless plug. Now, to your question.

On the top of the regulator knob on my compessor there's an arrow that shows if you turn the knob to the right a plus (+) happens, and if you turn the knob to the left a minus (-)happens. That means that turning the regulator knob to the right will increase the DOWNSTREAM pressure from the regulator.

I expect that your regulator will work the same way. Your compressor should have two pressure gauges on it. One shows the pressure inside the air tank, and the other, usually mounted on the regulator, shows the pressure setting that you have selected by turning the regulator dial.

If the gauge on the tank says 100 PSI, and the gauge on the regulator says 80 PSI, as long as there is more than 80 PSI air pressure in the tank, the air tools or air using devices downstream from the regulator will get a steady flow of air at 80 PSI.

If you have an air charge in your air tank (the compressor has run until the tank reaches the cut-out air pressure) then watch the gage on the regulator and turn the knob. As long as their is more pressure in the tank than you set on the regulator gage dial, the needle will move as you turn the knob. Then you can see for sure which way to turn the knob on your regulator. Hope this answers your question. Cheers, Bill.

Another visitor sent in this regulator question: I replaced the regulator reconnected it to the compressor using "plumbers tape" I think that is what it is called but can not get the knob to move either direction. The compressor fills with air but it continues to leak out the end opposite the gauge. which seems to have a plug in it. I have not connected the hose to it yet... maybe that would have helped?

My thoughts on this regulator question: If I am understanding you correctly, you used plumber's tape is thread sealant? The use of plumber's tape as a thread sealant isn't a problem, as long as the tape end isn't over any hole, causing a blockage or eventually allowing bits of tape to flow down the air line.

You go on to say "the compressor fills with air but it continues to leak out the end opposite the gauge." I am not entirely sure what you mean by this?

since I cannot see your regulator installation, I don't know what is on the opposite end of the gauge? Just one quick check. Are you certain that the regulator is installed in the right direction? Regulators normally have an arrow on them showing the flow path of the air from the higher pressure side (tank side) to the application side (hose side). Make sure the regulator is oriented in the air line properly.

As far as adjusting the regulator goes, if you cannot turn the knob, try pushing it down or pulling it up. Some regulators have a mechanism where the handle disengages from the spindle inside. Pushing in, or pulling out, on the regulator handle re-engages the spindle. If that doesn't help, please make another post, but this time, include photos so I can see what it is you are referring to.

Now It's Your Turn For Regulator Questions

For detailed information about air regulators, please visit: Compressed Air Regulators an information page on this website.

If your question is not answer, here is a form you can use to ask your regulator questions. Please review the existing questions first. If you can help other compressed air users by offering information on a comment on any of the current postings that would sure help.

Cheers and thanks, Bill



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