If you’re wondering how to adjust air compressor pressure switch control valve, you’ve come to the right place. We have general guidance on adjusting any air compressor pressure switch cut-in, cut-off and pressure differential.
We also have a list of compressor pressure switch adjustment procedures that are specific to air compressor brands and models that users have asked about in the past.
Table of Contents
- Why Adjust an Air Compressor Pressure Switch?
- Adjusting an Air Compressor Pressure Switch Considerations
- How to Adjust an Air Compressor Pressure Switch Guide
- Safety Measures for When Adjusting an Air Compressor Pressure Switch
- FAQs (Frequently Asked Questions)
- Reader Comments and Response
Why Adjust an Air Compressor Pressure Switch?
Having your air compressor operating at the right pressures is sensible for optimal use of your pneumatic tools. If air pressure is too high, you may risk detrimental damage to not only your pneumatic tools, but also your air compressor. The pressure switch is a very basic yet ever so important feature on your compressor.
Air compressor pressure switches determine how much air is needed to run a device. If your air compressor is set to run at 120 PSI and your tools require less pressure then it makes sense to reduce the pressure settings on your air compressor.
You risk damaging your tools with higher pressure than the recommended pressure settings. Throttling the pressure according to tool’s needs will save on energy and costs incurred in long running times. This will also result in less wear and tear on your air compressor and pneumatic tools!
Adjusting an Air Compressor Pressure Switch Considerations
All compressors have a pressure switch that controls the cut-in and cut-out pressures, which basically depict when the compressors motor turns on and off. The time between the cut-in and cut-out pressures is set by the manufacturer and is called the differential value. The cut-out happens when the air compressor is full.
You can reduce the time between the differential value to decrease the pressure or increase the pressure by increase the differential value. But, the latter is strongly not recommended. In very poorly maintained or old air compressors, operating at pressures above what is recommended can be very dangerous.
There are two types of pressure switches you must be aware of and know which one you have. One comes with a fixed differential value and the other with an adjustable pressure differential. Check your manual to understand which type you have and if you’re struggling, contact the manufacturer.
How to Adjust an Air Compressor Pressure Switch Guide
Now you have an understanding of the principles being adjusting an air compressor pressure switch control valve, I will now provide you with a how to adjust an air compressor pressure switch step-by-step guide so that you can do it yourself!
How do I adjust the pressure switch on my air compressor?
- Turn Off Compressor
First of all, unplug your compressor and open the cover of your pressure switch.
- Set the Cut-In Pressure
Begin with setting the cut-in pressure first. This will tend to be the screw closest to the manual or the big set screw. Turning the screw clockwise will increase the pressure (kick in sooner) and turning it anti-clockwise will decrease the pressure (kick in later).
- Check Cut-In Pressure
Drain out the release pressure in your compressor using the drain valve and then plug the compressor and run it. Check that your new cut-in pressure is working. If you want to tweak it further, unplug and drain the air compressor first to avoid electric shock.
- Set the Cut-Out Pressure
Now follow the same procedure to set the cut-out pressure, adjusting the differential pressure set screw. Turn the pressure screw clockwise if you want a higher maximum pressure or anti-clockwise for a lower maximum pressure. You should maintain a pressure differential of at least 20 PSI between the cut-in and cut-out pressures.
- Check Cut-Out Pressure
Run your compressor until it reaches the cut-out pressure and ensure it is doing so successfully.
This procedure mary vary depending on your air compressor pressure switch type. Some pressure switches can only be adjusted when under pressure. Don’t turn any of the screws when you get your new pressure switch, always check your manual to be sure you’re doing the right adjustments.
Most pressure switches are factory set at a cut-in pressure of around 80 PSI or 95 psi, with a pressure differentials of 20 PSI & 30 PSI, making the cut-out pressures 100 PSI and 125 PSI.
In fixed differential pressure switches, you will have a single screw threaded with a spring. Instead of adjust the cut-in and cut-out pressures individually, you simply turn this screw clockwise to simultaneously increase both the cut-in and cut-out pressure. Turning it anti-clockwise will simultaneously decrease them both.
Visit our Air Compressor Pressure Switch Troubleshooting & Buying Guide for information on faulty pressure switches.
Safety Measures for When Adjusting an Air Compressor Pressure Switch
There are some safety measures you should be aware of and abide to when adjusting an air compressor pressure switch. These are:
- You must always unplug your air compressor before adjusting the pressure switch
- Drain the compressor before tweaking any settings
- Never increase the pressure differential
- Perform the operation in a clutter-free environment with good ventilation
- Wear safety googles and gloves
FAQs (Frequently Asked Questions)
First of all, turn off your air compressor. To adjust the cut-in pressure, turn the big set screw on the pressure switch clockwise to increase the pressure and anti-clockwise to decrease the pressure. Now, adjust the differential pressure switch to change the cut-out pressure. Again, turning clockwise to increase the pressure and anti-clockwise to decrease the pressure. Ensure you check your manual before making any adjustments to know which type of pressure switch you have and recommended settings.
Most air tools require between 70 and 90 PSI which almost any light to medium duty air compressor can handle. But, you always want the compressor to supply more flow than needed to account for any pressure loss in the system. Therefore, your compressor should be set at roughly 100-130 PSI for the cut-in and cut-out pressures respectively. Ensure you check your manual for recommended pressures or contact the manufacturer.
The cut out pressure is otherwise referred to as the maximum pressure, the point at which no more air is being delivered. The cut in pressure is referred to as the minimum pressure, the pressure at which the system is allowed to fall to before the compressor motor kicks in and starts building pressure again.
There are multiple tell tale signs that an air compressor pressure switch is faulty. Inconsistent cut in and cut off pressures can often be a first sign – or the compressor not starting at all. For more information on troubleshooting pressure switches, see this detailed air compressor pressure switch troubleshooting guide.
Yes. Typically the pressure switch allows for the adjustment of the cut in / cut off pressure to ensure you have sufficient pressure and volume of compressed air to suit your needs.
Reader Comments and Response
How do I adjust air compressor cut in pressure?
I run a mobile service. my compressor holds 120 lbs. when it drops to 90 lbs it kicks back on. I want it to drop to 50 lbs before it kicks on. how do i adjust the cut in pressure on my compressor using the air compressor pressure switch?
Response by Bill
Ed, the thing that controls the air compressor cut in pressure is the pressure switch. It also controls the compressor cut out pressure level too.
I’m puzzled as to why you feel the need to reduce the cut in pressure to 50 PSI?
Wouldn’t the same thing be accomplished by turning your regulator down to 50 PSI?
Regardless of the pressure in the compressor tank then your air tools would then only see that 50 PSI, would use less air because of the lower pressure setting, and thus would reduce the frequency of compressor cut in.
If you must change your pressure settings, and I generally advise against it, as they are factory set for good reason, then one of the two threaded shafts with the nuts pushing down on springs inside your compressor pressure switch will adjust the cut in and the other will adjust the compressor cut out pressure levels.
That is assuming that your pressure switch is accessible, and has those two springs I spoke of, since you don’t mention the make or model of your air compressor.
How to adjust the compressor pressure switch down?
by Terryl Cozart
I want to adjust the pressure switch down.
I have a Dewalt D55168, 200 PSI 1.8 HP 15 Gallon tank I picked up used the other day. Everything seems to run just fine except it hasn’t cut off on it’s own. I got chicken and cut it off manually. It has reached 200PSI, but it won’t cut off. This thing scares me a little. I would like to cut the pressure down to 175 or so. This seems a little more manageable to me, I just don’t know how or if you can. Any help you can give me would be greatly appreciated.
Response by Bill
Hello Terryl, very nice to hear from Tupelo. Thank you for visiting this site and for writing in.
I suspect that your pressure switch has failed on the high pressure cut-out setting.
Yes, you can adjust the cut-in and cut-out pressure level yourself, but I think that with your switch you will be trying to adjust it in vain.
You are quite correct to be intimidated by the compressor. I don’t know of many smaller that exceed, say, 175 PSI at the high end and this one is rated for 200 PSI.
Do yourself a favor too, and once the pressure gets up to 170 PSI or so, manually toggle the PRV by pulling on the ring to make sure that it’s free. In the event that the pressure in your tank reaches the PRV threshold, it will open and vent the air to prevent pressure rupture. Manually toggling the PRV open and closed will satisfy you that it will actually work when you need it.
Watch the pressure gauge when you close the PRV and let it get to 210 PSI. Doesn’t shut off still?
Change your pressure switch. I think that’s your compressor problem.
I appreciate the response. You said just what I was thinking. Nice to be backed up.
Step by step instructions for setting the cut out pressure on DeWalt D55168 air compressor
Can you please give me step by step instructions for setting the cut out pressure on the DeWalt D55168 air compressor. I would like to set it to 150 psi.
The instructions provided were very vague.
Response By Doug in s.d.ca
Depends on whether you have a type 1 or type 3. If not sure, pls send a pic of it with cover removed.
How to adjust pressure switch setting of Kobalt compressor model K7060HFV
by stratton whitaker
(st louis, mo, usa)
How to adjust pressure setting of a Kobalt K7060HFV air compressor? I have a Kobalt K7060HFV air compressor. Works great, but the pressure is set at 80psi. How can I adjust the pressure up to 110psi?
You say the pressure is set at 80 PSI? Can you tell me where on your compressor is that pressure setting set? In other words, is it the pressure switch setting, or is it the outgoing air regulator setting?
To adjust the compressor system pressure requires re-setting the pressure switch, and I don’t recommend that.
If it’s adjusting the downstream pressure to your tool, that’s done with the air regulator.
If you aren’t sure, please add a comment and we’ll dig further into this.
How do you adjust the cut-off pressure setting in Husky compressor?
by allan keller
I have a Husky 60 gallon stationary air compressor Model #C602H that i have adjust the cut-off setting. the setting is too high for my equipment.
Adjust Model #C602H cut off setting
Allan, your Husky air compressor is configured to run ideally at the cut in and cut pressures that came with the OEM pressure switch.
Reducing the cut out pressure setting will really only result in increased wear and tear on your compressor.
I suggest that you leave the pressure switch alone!
What you need to do is adjust the pressure setting on your air regulator to the minimum pressure that your air equipments operates best at.
In this way you will have plenty of air to run your tools – assuming the air tool demand is less than what the air compressor can deliver – and at the same time your compressor will cycle less frequently which is good for reducing time loss and cost in compressor maintenance.
Thanks Bill this was good information
How to Adjust Compressor Cut Off pressure on Ingersoll Rand 375 Compressor?
by Rory Mahaney
IR 375 Diesel driven, screw compressor; pressure switch adjustment:
Compressor runs great.
Recently replaced pressure tank filter to resolve blotter test issues (oil in the blast air) and it fixed the problem.
I want to set the performance pressure to 145psi. Currently, I have to keep the air outlet valve open to prevent the pressure release valve from popping off at max pressure on the gauge (150psi) and spraying hydraulic fluid everywhere.
How do I adjust the pressure cutoff, and is there anyway to test the electronic pressure sensor located near it in the same line on top of the hyd/air pressure tank?
Adjust pressure cut off IR 375
by: Doug in s.d.ca.
Before getting to that, have you cleaned the PRV ?
If not, it’s almost certainly popping prematurely.
The pressure sensor is just a pressure sensitive resistor, so the easiest way to check that is with another gauge on the separator tank or receiver.
by: Rory Mahaney
I have previously replaced the PRV (150psi), as this was my first line of resolution.
I know that the valve on the right in the pic above, is the cutoff adjustment, just wondering what the proper procedure for adjustment is, as I have adjusted the top screw in and out, resulting in no change of the compressor shutting off at a lower pressure than that of the PRV.
Is there a technical name for this “pressure adjustment valve” that I am not aware of? If I knew that, it is possible that I would be able to purchase a new one, assuming the current one has worn out.
Pressure cut off IR 375
by: Doug in s.d.ca.
I think perhaps the reason the adjustment is not working, and given that you have to leave the outlet open, means that the thing is not loading/unloading properly, as in the load valve is stuck.
After you’re sure that’s OK, then the adjustment will probably work, too, unless something else is stuck…
by: Rory Mahaney
Thanks so much! I’ll check the unload valve and go from there.
Pressure cut off IR 375
by: Doug in s.d.ca.
Sure. hope I helped.
Let us know how it turns out, OK?
If you have any questions regarding how to adjust an air compressor pressure switch, please leave a comment below, with a photo if applicable, so that someone can help you!