There is quite often a misconception about compressor regulators that we will try to dispel here, as well as giving you lots of information about how to best use your compressed air regulator.
While probably not all, most air compressors that have a tank will come equipped with an air regulator. It is typically located on the discharge line from the tank, upstream from the discharge coupler, which is the coupler into which you plug the connector on your air hose. Depending on the make and model of your air compressor, your compressor regulator will look something like the one in the image.
Your compressor regulator may be a different color. Your regulator may be bigger or smaller, it may have a smaller or larger air gauge or the air gauge may not even be directly attached to the regulator, your regulator adjustment knob may look different, yet all air regulators are basically similar in function to the one shown.
Using Compressor Regulators
Using the regulator is pretty straightforward. If you turn the regulator adjustment knob in a clockwise direction, that normally elevates the regulator pressure setting. Turn the knob counter-clockwise and the regulator setting is reduced.
Whatever pressure is displayed on the regulator gauge – not the tank gauge since your compressor typically has two gauges – is the pressure of the air stream exiting the discharge coupler into your air hose.
Some regulator adjustment knobs lock by either depressing them or pulling them out. If you find that you cannot turn the regulator adjustment knob, try pushing down on it or pulling it up. If it has a built-in adjustment lock, that should unlock it.
About Compressor Regulators Misconception
The most significant misconception about compressor regulators is that they can raise the air pressure!
If your tank pressure is 100 PSI for example, you can increase the discharge pressure by turning the knob in a clockwise direction. If you try to dial the pressure up past the tank pressure of 100 PSI the regulator gauge needle will stop at and display the tank pressure of 100 PSI, and that’s the pressure that will be exiting the discharge coupler to the air hose.
The air regulator can only adjust pressure down. No air regulator can adjust the pressure up past whatever the pressure is in the tank or air mains.
What Good Are Regulators Then?
The compressed air regulator is an important device. Why? Because it allows you to dial the pressure down to the the absolute minimum required by the air tool you are trying to operate.
Running your air tool at the minimum operating pressure extends the life of the air tool, reduces the amount of air used – which cuts down on energy cost to compress the air – and reduces the cycle frequency of the air compressor, which has positive ramifications for the compressor life and maintenance cycle.
Always adjust the air regulator pressure setting to the minimum pressure level required to operate any of your air tools.
Can You Have Multiple Air Regulators?
Absolutely you can. Many industrial plants plumb their compressed air up to a ceiling mounted air main that circulates the plant. The air pressure in the air main is typically the highest pressure that the plant compressor can generate.
Drop lines are installed from the air main down to the shop floor to supply compressed air to various pieces of equipment. Each machine or piece of equipment may have a different minimum operating pressure, so there will be a regulator (and typically a filter too) installed just before each piece of equipment so that the pressure can be set to the optimal performance level.
So too, in your home shop you can adjust the pressure for your air line on the regulator in the discharge line from the tank, and if desired, you can install air regulators anywhere else in the line to be able to further adjust the air pressure if you have multiple uses of compressed air.
Compressor Regulator Maintenance
For most of us DIY type folks with home or small shop air compressors, the regulator that came with the compressor will be a cheap one, mass produced in some foreign land for pennies each, and sold to the compressor assemblers for not much more than that, we expect.
The diaphragm inside the regulator upon which the compressed air presses to control the downstream pressure will crack in time, through high cycle exposure, from contamination of the diaphragm by compressor oils, debris in the air stream, or drying out of the regulator diaphragm over long periods of inactivity. If the regulator diaphragm cracks, your regulator will leak all the time.
The regulator gauge is cheap as well, and over time the innards corrode, or an impact might shatter the gauge-face cover.
Industrial air compressor regulators typically have a good supply chain of spare parts. They are expensive enough to warrant dismantling and repairing rather than tossing them out.
The typical DIY compressor air regulator does not enjoy a good supply of parts. With the price of a new regulator being in the $20 – $30 range, it’s hard to justify buying a kit (if you can find one) for almost that amount of money and spending a couple of hours tearing the regulator down and trying to get it working again.
In other words, the low end regulators are basically disposable when they fail.
You can replace the gauge on a regulator for around $7 – $10, however. If it’s the gauge that goes, do get a replacement.
If the regulator starts to leak, sure, try to find a diaphragm for it and fix it if you can. For us, it’ll be time for a new compressor regulator at that point.
Since most replacement regulators come equipped with a display gauge, if the old gauge is still working, keep it for a spare.
Got a question about your air compressor regulator? Use the comment form below to ask it, and we’ll help if we can. If you see a question about air regulators here, add your comment if you can help. Only questions and comments about compressor regulators will be approved for this page.
Hi, great article! I have a porter cable cmb15 that the main tank goes to 150 psi. The problem is that it will only go to 150 if I have the regulator set to max. Otherwise it follows the regulator. If I set the regulator to 100 then the main goes to 100 and it keeps running while it bleeds off the air somewhere. Is it the regulator that is the problem?
Thanks for your kind comment. As to the regulator, it has nothing to do where the compressor starts and stops, that’s the pressure switch job. That the compressor runs and runs when the pressure regulator is set to 100, and gets to 150 PSI when the regulator is set there certainly suggests an issue with a leak at the regulator. You don’t indicate what the normal cut out pressure of your compressor is, so I… Read more »
My regulator seems to work ok, but the pressure gauge does not drop when dialing down air pressure. I installed a new gauge but have the same problem. It reads tank pressure but but doesn’t drop when output pressure is dropped.
Tim, your compressor has two gauges, yes? Is the one reading tank pressure showing a higher pressure than the pressure you want downstream to your air tools? And, are you saying that with, for example, 100 PSI in the tank, if you dial the regulator down to 50 PSI, the regulator gauge doesn’t move to reflect that lower downstream pressure? Was the regulator working before? Have you pulled up on, or pushed down, on the… Read more »
I have a Bostitch CWC 200ST that has the same regulator pictured by Andy back in July. The knob on mine is stripped out and needs to be replaced. But can’t figure out how to disassemble the regulator to take the knob off so I can insert it into the panel. It has a hex piece of metal on the end of the knob screw that prevents the knob from coming all the way off.… Read more »
OK, mine is a little different.
If the photo of the compressor is of your compressor Scott, you’ll want to remove the metal cover of the whole assembly to get a look at how the regulator connects in. These regulators are cheap, costing a few cents to manufacture in an Asian country, and sell retail in North America for, typically, under $10. However, if the regulator is part of the manifold under the metal plate, you likely won’t find another to… Read more »
thanks willyr. Yes that’s a pic of my compressor. As you can see from the pics attached the black cap has to come off so you can unscrew the red ring and insert it onto the panel.
The little hex piece of metal is what stops the knob from coming all the way out.
Thanks for the pics, Scott. As I thought, it is a cast manifold, but it looks like you are in luck, and that is, the regulator threads onto the pipe in behind the metal face plate. Done some damage to the knob in trying to get that off, looks like too. Yet I’m a bit puzzled, as your first pic looks like the regulator has been disassembled. Is that not so, or is that the… Read more »
Sorry, forgot to identify the pics. The two on the red desk are of the disassembled new replacement regulator. The two on the workbench show the old one on the panel. The first pic is of the new disassembled regulator fully unscrewed but held into the housing by that hex piece of metal pinned onto the screw thats connected to the knob. The second pic is just that new part screwed fully in so you… Read more »
Scott, not much wisdom I’m afraid. I believe the regulator handle / knob is typically attached with a snap ring, and, a sharp pull upwards (with gloves on) should remove the handle. I take it you’ve tried this already?
I have a new Husky oil free 8-gallon air compressor I purchased this year. I either have a [ outlet / downstream ] regulator malfunction, or I need to be educated on the normal operation of the regulator gage on the compressor. The compressor has 2 gages: one shows me the tank pressure and it is preset by manufacturer to shut the compressor off at 150psi, which it does properly. ( And when tank pressure… Read more »
Keith, the upstream (tank) gauge does not control anything. It reveals the tank pressure, reflecting the pressure changes in the tank. It’s the pressure switch that determines when the compressor goes on and off. Just want to make that clear. The downstream gauge is on the outlet regulator. As long as that regulator is set at a pressure that is below the tank pressure, it will maintain the pressure of the air stream out the… Read more »
I have AS18-2 air compressor. When I try to turn the valve for adjusting the air, it turns slowly in both ways and it feels like it’s been tight and the pressure is always on same level. Can please tell me if there is any way to fix this issue or do I have to buy new pressure valve? Thx
The knob on the pressure regulator is supposed to turn in both directions, one way to dial up the pressure, the other to dial it down. Are you saying that regardless of which way you turn the knob, the reading on the regulator pressure gauge remains the same? Before chucking out the regulator and replacing it: 1) is the tank pressure gauge showing a reading that is higher in pressure that the setting on the… Read more »
Sorry that it took me so long to answer you back. There is only one pressure gauge, that is on the regulator. I’ll send you pics of it. When I turn it on, with my ab gun connected, the BARS are by spec(3-3.5), but when I push on ab gun, it goes to 10ps. If I pull the gauge up and try to turn it left or right, it turns very hard and clicks every… Read more »
And I didn’t pick up the fact that yours is an air brush compressor. One gauge is normal. This compressor has no tank, and runs on demand. In other words it compresses air as the air is being used and stops when the air stops being used… right? If you are saying that when you start using air the regulator gauge moves up to 150 PSI (10 Bars) from 50 PSI or so (3 –… Read more »
I installed a regulator on a 2-gallon portable air tank. Can I also use the regulator to fill the tank or will air flow opposite the direction intended damage the regulator?
Theo, when you say “using the regulator to fill the tank” I take that to mean that you wish to supply air to the tank by flowing air back through the regulator and into the tank? No, I wouldn’t do that. The regulator is designed to flow air one way, trying to flow air back through it could result in damage to the regulator, and will certainly result in air blowing out of the relief… Read more »
I put a new regulator/moisture trap on my compressor. It builds pressure in the tank fine as long as the regulator is at 0. As soon as I go to adjust it to correct psi, it dumps all the air out of tank. Nothing reading on tank or regulator valve and won’t build pressure again until regulator is back to 0……help
Chad, is there an arrow on the body of the filter/regulator somewhere? It sounds as though they are installed backwards. Make sure that the filter is first and then the regulator, and if both in one body, ensure that the arrow on the body of the regulator (or somewhere on it usually) is pointing at the discharge coupler, not at the tank.
Ok, found out that the airbrush hose had several pinholes in it, but being braided cloth over it….it was harder to hear. I bought a new airhose and it holds pressure now. The flow arrow is in the right drection but now tank won’t build pressure past whatever setting I set on the regulator. For example….if I set to 20….tank only builds to 20…..if I set to 80…it builds to 80. This makes the compressor… Read more »
Chad, typically the air regulator has nothing to do with the cycle of the compressor. That’s the pressure switch’s job, and normally changing the regulator setting will have no impact on that. Having said that, before we go further, what’s the make and model of the air compressor, please. You mentioned airbrush hose, and if it’s an airbrush air compressor, and it’s a demand compressor, meaning that it comes on when the air is used… Read more »
It is an airbrush compressor. Sil-Air 15a. I can hear air leaking out of the top of the regulator even though it’s new. It has a 1 Liter. tank but I will only be running at around 20-25 psi. I don’t believe it should run full cycle all the time or that would defeat the purpose of a tank. It is almost like whatever psi the regulator is set to, if it exceeds that then… Read more »
The regulator is a “relieving” type, meaning that if the downstream air pressure is higher than the regulator setting, then the higher pressure from downstream will vent out the top of the regulator. If you disconnect the air line, and air is still venting out of the top of the regulator, then that suggests that the regulator diaphragm is compromised, and air is leaking through it and out the vent hole. If the latter and… Read more »
I have a 21 gal Central Pneumatic compressor from HF that was given to me by a friend. It will successfully fill to 125 PSI and cut off. I had a ball valve between the regulator and the quick connect for the hose. When I would connect the hose with just a simple air gun attached and open the ball valve the pressure on the regulator would drop from 90 PSI to zero. The motor… Read more »
Oh Andy, you are having fun, aren’t you with your interesting – and expensive – series of compressor issues. So sorry you’re having these issues. Unless the ball valve was not opening when you opened it all the way, then having it in the circuit between the regulator and the discharge coupler (into which you plug the connector on the air line) should not have affected the air flow at all. So that should have… Read more »
Thanks for your detailed reply. I doubt there was an issue with the ball valve but I took it out of the equation anyway. I do believe there was a slight leak involving the ball valve and/or coupler (or the joints). The tank has a pressure gauge on it directly (not part of the pressure switch. From empty, the compressor will fill the tank to 125 psi and cut off. It will cut back on… Read more »
If I understand your comment correctly, the regulator arrow points to the discharge coupler? If so, that is correct. No, the PRV cracking pressure should not be 125 PSI if the cut out pressure is 125 PSI. Either replace the PRV or if you can adjust the cut out pressure down by 5-10 PSI on the pressure switch, that should resolve that issue. If the tank check valve were leaking air would be flowing out… Read more »
So, I took off everything off past the pressure switch. So, no regulator or connect. In theory, if I turned it on then, it should be dumping air straight out. When I turned it on, it filled the tank and hardly anything came out. So, I’m suspecting it’s either the pressure switch or the actual attachment to the tank. I removed the pressure switch after disconnecting everything. It looked clean and clear. There was some… Read more »
If you took off the pressure switch there is nothing between the end of the pipe and the tank, and I guess the tank is empty of pressure yes? The motor wires must now be exposed, and you could run a wire to each from a power cord to start the compressor if you are comfortable and safe doing so. If you do, what happens? Does air blow out the nipple from the tank?
I did as you suggested and got just a trickle of air coming from the nipple. In fact the tank filled. I cut it off at 100 psi and could hear a small amount of air exiting but that was it. So, I guess this means the tank nipple is clogged. I used a little usb endoscope camera I had to look inside the tank. Overall, looks ok but I couldn’t see the exit area… Read more »
Been messing with compressors for a lot of years and have never run into this. Do you know if the compressor was ever turned over? If the tank hadn’t been drained regularly, and if the compressor turned over, it is possible sludge from the tank got into the nipple. What to do? With the tank drain open, and if you have access to another compressor or a tank with air, blow air into the nipple… Read more »
Ok. I stuck a large nail into the hole and gave it a light rap with a hammer. Whatever was stuck finally came loose and air is now flowing properly. What a pain. Anyway, thanks for the help. I now know how a compressor works. 🙂
I just purchased a cheap Craftsman 2.6 scfm with a 6 gallon pancake tank (CMEC6150 ). My intent is to use this to fill tires, and some small tools. However, in the event I need to use my Ingersoll Rand professional impact wrench to take off a lug nut, I’m expecting to get 3 maybe 4 sec’s on 90 PSI air. Would I likely need to replace the factory air regulator on this small air… Read more »
Probably not, Curtis. The impediment will be the small size of the pump and tank. You won’t be happy with the use time of the 1/2″ impact wrench, but it should work OK for a bit.
I have a hitachi 6 gallon EC510 compressor. Everything runs fine, including the regulator as far as adjusting the pressure to what I need. The problem Im getting is after shooting a few nails. Whether 1 1/4 roofers or 12d framing nails at 100 lbs or so, after the first 2 or 3 nails (shot within 2-5 seconds of eachother) the following nails set less and less until I wait 5-10 seconds to shoot again.… Read more »
Sure sounds like the regulator is the problem, and that you have to buy a manifold to get a regulator sure seems unfair, and particularly when the manifold price you refer to is just under 1/2 the price of a new EC5 compressor. You may have to make your own manifold using off-the-shelf brass fittings from a decent hardware store, find a used EC to cannibalize for parts, or, bite the bullet and buy a… Read more »
I was afraid of that. And yes it almost seems silly to pay that much for a part when I could have a brand new compressor for not a whole lot more. Could it possibly have anything to do with the pressure gauge attached to the regulator or manifold rather? I had planned on taking it apart but figured I’d consult the experts first to possibly pinpoint the issue or find that it may be… Read more »
The pressure gauge is a “dumb” device, meaning it only displays the pressure that is reaching it. If it is showing a pressure drop, it’s because the pressure to it is dropping, so no, I don’t think it’s a bum gauge. But, dump all the air and swap the two gauges to determine if one of them is at fault. Otherwise, you’re likely stuck with the options noted in the previous post.
I have a regulator that is making a trumpet like sound when air passes through it. What could cause this?
Likely the diaphragm inside the regulator has a crack, at least, that would be my first guess. Is it a new one, just installed? If so, check to be sure that it’s installed with the air flowing the right way.
Brand new 1/2″ 144scfm 150 psi regulator, it was in line just before a filter/condenser. I moved it back to the quick connect on the wall and that seemed to fix the issue. If it comes back I’ll have to assume the diaphragm is cracked. Thanks!
Tyler, glad that resolved it so far. A thought though… are you familiar with the acronym FRL? It stands for Filter, Regulator & Lubricator. They are in that order in purpose as putting the regulator before the filter does not stop water and any other airborne debris from the tank from interfering with / fouling the regulator innards. That’s why it’s suggested that the filter always get installed first. Crud in the regulator might have… Read more »
Yes I am familiar with FRL’s but good to know! The regulator is for a piece of equipment that has the inlet on the filter, I didnt want to tear apart the equipment to get things in a logical order. We do have an FRL system for the air supply before the regulator. Cant rule out dirt but also seems the filter was impeding airflow. Thanks for the help.
Hi All,
please I’m so confuised I have big problem with the quincy Compressor air.
the regulation are fail what can I do to reasolv this problem?
normaly it’s will be regulate between 5 to 10 barg to load and upload
Joris, if it’s a regulator on a Quincy compressor I’d like to move this thread to the Quincy page, assuming you can tell us what the model number of your Quincy is, and upload a photo or two of it. Also, what does it mean to you that the regulator fails? Is it that the downstream pressure is wrong… what exactly?
I have a quick question that I’m hoping can be answered before tomorrow morning for school. My question is if a gauge is manufactured to have the ability to read out from 0 to 100psi, why would someone want to re-range it to read only 10 to 70psi?
Not sure what you mean by re-range it Alan. However, a regulator gauge range of 10-70 PSI should give more accurate pressure readings, assuming the regulator and regulator gauge isn’t a piece of junk. General purpose regulators may show a pressure that could be 3 +/- PSI off from true, while a precision regulator might be only .25 PSI off from actual. The use of a precision regulator with a small pressure range would allow… Read more »
Hello, can you explain to me the difference in ratings of compressed air regulators? I have a very inexpensive regulator filter combo that I want to put on my 60 gallon 175psi max air compressor. The regulator is rated for 80scfm @ 100psi and says that the max pressure is 145psi. My question is, does the 145psi max mean that the regulator is only meant to regulate pressure as high as 145psi and anything above… Read more »
Hey Brandon. If a regulator is rated for 145 PSI, then that’s the highest pressure it is designed to handle and it will not register pressure above that level. In other words, if you flow 175 PSI into it, the regulator can only regulate up to 145 PSI. Will 175 PSI damage a regulator rated for 145 PSI? I would expect so, but it may not. Nevertheless, prudence would suggest that you replace the 145… Read more »
Hi folks – what happens if I install the regulator in the wrong direction? I recently took apart my regulator to reseal the component threads and realised that the regulator does not have an airflow direction marking. Can anyone tell from these photos which way I should reassemble it? Any help would be much appreciated!
If you install it with the flow going in the wrong direction, you will not get regulated air pressure at the air tool, and typically the regulator gauge reading will show the tank pressure instead of the pressure you have set the regulator for. Odd regulator this one. Not seen one with a coupler, fitting and two gauges before. What is the compressor it’s off of, please?
Cheers Willyr – this is the compressor…
Thanks for the .pdf. That regulator appears to have a channel inside that allows full pressure tank air to get to the tank gauge, and then regulated air to be displayed on the regulator gauge and then allow that regulated air to flow to the discharge coupler to get to the air tool. While I’ve certainly not seen every regulator, in North America regulators (about $14 US on line) accept incoming full pressure air, display… Read more »
Cheers willyr! Yeah I figured replacing it might be a good option. Thanks so much for your help – very much appreciated!
Where can I find a regulator #243for a lIl red air compressor model BAR233P?
Roy, I cannot find any information about a “red” air compressor BAR233P… none! Is “Red” the brand name, or model of a different brand name air compressor? Nor does the regulator part 243 return any information for a compressor, but it does return gas regulators? Perhaps you might post again with a photo or two of your compressor showing the old regulator if you still have it, or where on the compressor it would go… Read more »
Hi. I just got a new Husky air compressor. I am having trouble setting my regulator valve. I set it to a maximum of 90 psi, but my compressor keeps pumping up until I switch it off. Am I doing something wrong? Thanks in advance for any help. Jack
Hello Jack. If I understand correctly, you may be laboring under an understanding that many new compressor owners do, and that is that the air regulator, the one you’ve set at 90 PSI, has something to do with turning the air compressor on and off. It does not. It is the pressure switch that does that, and, depending on the model of Husky air compressor you have, that cut out, or compressor stopping pressure, may… Read more »
Hi. Yes Willy R., your information answered my question. Thanks very much. Regards, Jack Schrader
I have an iwata compressor and the knob will not turn to allow air flow. The knob is in the up position, just will not turn. I have used it for about four years and the compressor was working fine a few days ago. The tank can still be drained from the water trap filter bleed. Can the regulator be replaced with a third party regulator. It’s the Iwata IS-900 model and replacement parts are… Read more »
Jim, if the compressor is off warranty, you can put any part on it you wish with no penalty from losing that warranty. And yes, if this were my Iwata, I sure would replace the Iwata combination F/r (filter regulator) with a non-oem one for a fraction of the cost. Make sure the element is the same micron rating and the pressure range of the new setup is close to the old.
Hello- I retrofitted a portable air tank and accidentally hooked up the air pressure regulator (0-15 PSI) backwards with the air flow arrow pointing toward the tank. and realized this when I filled the tank to roughly 50-65PSI and the air regulator gauge did not work properly. I switched the regulator around and it appears the gauge is still not working properly. It never drops to zero when the valve is completely closed and only… Read more »
Do I understand correctly that the original gauge is rated 0-15 PSI, and it received pressure above 50 PSI? I suspect, if that’s correct, that the over-pressure has damaged the gauge. No, I don’t think it’s a bad gauge, just a broken one. However, check with the gauge manufacturer to be sure. Good luck.
i purchased a new dewalt 165psi , 6 gallon pancake compressor DWFP55126. the tank gauge works fine,it turns on and off at the correct cut in/off points. my issue is with the regulator, when i set it to 90psi and use a nailer or just the blow gun, the pressure more than not does not return to 90psi after i discharge some air. sometimes it goes as low as 75-80 psi and as high as… Read more »
Peter, my experience has been that a general purpose regulator like the one on your DeWalt DWFP55126 has an accuracy range of 3-5 PSI over or under the set point. For purposes of air compressing and using air in air tools, for most of us that’s plenty accurate. Having said that, what you say is happening is that you have, for example, 90 PSI set on the regulator, you use your air nailer, and rather… Read more »
Thanks for your reply. i dont believe there is any problem with air flow as the nailer works perfectly as does the blow gun. if i turn the compressor off, the regulator pressure ‘will drop at the same rate and read the same as the tank pressure, in this regard the regulator gauge seems to work fine. a couple things may mean something and may not, bare with me haha. if i let very small… Read more »
If you turn the compressor off, and bleed air from the tank, yes, the regulator gauge reading will match the tank gauge reading once the tank pressure drops to the regulated pressure of the regulator, and both will drop to zero. If you blow air out of the tank with a blow gun on a line, briefly, ten little puffs (hard to be sure what those are since I’m not seeing what you mean by… Read more »
that is my opinion also, thank you very much!
I have a Campbell Hausfeld WL802600AJ, 155PSI, 29 gal tank. The Regulator and both gauges and outlet valve receivers are ll one unit. When I turn my regulator knob counter clock wise (lower), the pressure releases from both the tool outlet and the tank gauges. I cannot remove the regulator and turn it around to face the outlet valves, it does not come apart. Do I need to buy an entire new unit? Additionally, the… Read more »
I’ve put your two posts together. Thanks for the added info. It does sound as though the regulator diaphragm has cracked, or a seal has let go, Ray. If you search for parts for your compressor, you will see the much of what is attached to the “manifold” can be removed. You can, then, make the base manifold from brass parts from a good plumbing wholesaler, and add the removed parts to that. You can… Read more »
Hi, I am pretty new to the world of air compressors and I am trying to better understand how I can utilize air regulators. Here is my question. I have a very large towable air compressor that produces around 185CFM at 100 psi. I have a dessicant air dryer that has a three stage filter that is connected inline between the tool and the compressor. This dryer is rated at 142PSI and about 40CFM airflow.… Read more »
Sorry John. I’m not getting it. Your compressor is putting out 100 PSI, yes? Your desiccant dryer is rated for 142 PSI. The air tool needs 100 PSI. So what is the problem? Is it that the 185 CFM coming out of the compressor will overwhelm the dryer? That being the case, you’ll want to put a manual valve (not a regulator, but a valve) to be able to reduce the flow to the level… Read more »
Hello All,
I have an Ingersoll and Rand water trap regulator. It has been working well for 8 months until today. The regulator still does it job at lower psi’s, but once I try to spray at higher pressures, it shoots straight to 150psi and stays there. I don’t want to buy a new one as they run around $100, any ideas about how dire this problem is and what I could do to fix it?
By water trap regulator, I take that to mean that it is a combination filter/regulator? If 150 PSI is the upper pressure output of your compressor, then I would suspect either the spring in the regulator is going and / or the diaphragm is failing too. The flow capacity and port size will be the deciding factors in replacing it, AJ, though some of these better quality regulators do have repair kits that cost less… Read more »
I bought a used DeVilbiss Pro Air 2, model # 430-1 , max pressure 125. When I turned it on the first time, it built up pressure to about 125 and air started coming out of the small relief hole below the pressure line on the regulator. I was able to find a new regulator and installed it. Same thing. It built up pressure until about 125 and air started coming out of the small… Read more »
Hi Kurt. My guess is that you’ve got a leaking tank check valve. Perhaps you might remove it, clean the seats, and replace it and then check and see if the problem persists? Make sure you’ve dumped all the air before disassembling the fitting on the tank. Let me know how it turns out would you?
hi everyone my question is i set my compressor outlet @2.5bar but when it compress down to 2 bar when it use from tank it rise to the previous so how can i fix it
A bit more clarification please. If the regulator is set for 2.5 bar, that’s the pressure that the air tool will see, as long as the air pressure in the tank stays above 2.5 bar. If the tank pressure falls below 2.5 bar, the regulator can no longer maintain the downstream pressure. That would suggest to me that whatever you are using air for is pulling more air than the compressor can generate. Is this… Read more »
I have an air compressor that I just purchased. When I decrease the air pressure the regulator leaks until the pressure of the entire tank matches the setting on the regulator. Any idea what is wrong?
It sounds as though the regulator is installed backwards. By that we mean that the arrow on the regulator is pointing towards the tank, and not towards the discharge coupler. Try – with the tank empty and the power cord pulled from the socket – removing the regulator and reversing the flow. Let us know if this helps, will you?
It’s working correctly. It’s just bleeding off the pressure in out going side of the line.
Okay. So you say the regulator is “working correctly”? Nope, not if it’s bleeding air. Did you determine if the arrow on the regulator is pointing to the discharge coupler or towards the tank?
Hi, I have an Iwata Smart Jet Pro that has developed a problem. I was unable suddenly to turn the pressure regulator knob. At the same time the pressure gauge stopped working, not budging from zero despite the compressor blasting air to my airbrush. I assumed that the problem stemmed from the pressure knob. I took advice and removed the knob cap and loosened off the nut. I can now move the knob again, however… Read more »
Short of tearing down the existing regulator, trying to determine what part(s) has failed, trying to find the part(s) and then reassembling, replacing the whole regulator would be the choice as far as we’re concerned. These regulators are not expensive. Just make sure when you install the new one that you point the arrow on the body of the regulator towards the discharge coupler – the coupler into which you plug your air line.
My air regulator knob is very hard to turn. Is there a lubricant that should be used? It’s not leaking.
No lubricate that we know of. If pushing or pulling on the regulator knob provides no benefit, we can only assume that some air borne debris has created a friction issue inside and it may be time to replace the regulator.
Hi Willyr, first off, thank you for this site and the wealth of information shared! i’m a compressor newb and learning along the way. Anyway, my question is with regards to my old sears/craftsman compressor (model 919.717521 2hp) from 1980 (bought from the original owner and it’s in beautiful shape!). I think there’s a leak somewhere in the regulator. I’ve tried googling for parts kits and ended up talking to a bunch of compressor repair… Read more »
just to add, i’m looking at part 69/70. guess i can take a real pic with the cover off. also would like to the new parts (if needed) to at least fit as closely as it can through the 3 holes in the plastic cover (or am I asking too much?! ) one of the techs i spoke to even suggested skipping or plugging the regulator and just running straight off the tank. but i’m… Read more »
Okay, the image came through fine Romney, and we see the regulator. We expect that you will have a hard time finding parts for this regulator, though the people to ask about this for sure are at Sears service. Assuming you cannot, we expect with some manipulation a general purpose, panel mount regulator can be fitted into the hole in the cover, and plumb into the discharge line from the tank. Take the old regulator… Read more »
Thanks for the speedy reply WillyR! very much appreciated! Yes, definitely leaking when dialing up. looks like it’s a one piece unit with the tank pressure gauge off the manifold so i’m guessing i’ll be needing to replace both with some dual unit and or separate units with like you said, figuring out the best fit with some plumbing. guess i can even live without the plastic console cover on worse comes to worse piece… Read more »
just adding more pics
here you can see the pipe plug on top of the compressor manifold
Gave compressor a little cleaning.
As long as the regulator has access to air from the tank, then where you plumb it is up to you. Good luck.
Hi, I just installed a Kobalt 3/8 in regulator on my twin tank Central Pneumatic wheelbarrow compressor. I bought it used and when I ran it it would pop off at 150 tank pressure. This regulator continuously bleeds off pressure and won’t let me get any higher than 60 psi and tank pressure can’t build any higher than 70; did I just install a broken piece of junk?
Loni, we’re a bit confused. You speak of the Kobalt regulator, and then refer to it popping off at 150 PSI. The regulator does not “pop off”. Are you, perhaps, referring to the PRV? If you are referring to the regulator, please confirm that you have installed it with the arrow on the regulator body pointing towards the discharge coupler, and NOT towards the tank. If it is pointing to the tank, remove the regulator… Read more »
I’m having the same issues with the cobalt regulator, it continually bleeds ( seems to be out of the handle)
I have a mini air compressor are the air tank pressure and the air regulator suppose to read the same . My tank reads over 200 in the red the regulator shuts off at around 100
We are a bit confused by your question. The regulator does not shut anything off. It is adjusted by a knob to set the downstream air pressure at the level you want for your air tools. If the regulator is set for 100 PSI for example, and the tank has 150 PSI in it, then the downstream air tools will get a steady stream of air at the 100 PSI you have selected on the… Read more »
Howdy, I have an old Emglo MK5HGA-8P compressor and the regulator screw broke. It is an old enough unit that I can’t find parts anywhere for it. The regulator screws into a manifold and comes apart easily, do you know of anywhere to get parts or do you know of a screw in replacement that will go in the manifold?
Indeed, it seems that the regulator repair kit for this wheelbarrow compressor is no longer available. The further issue is, we do not have access to the compressor to unscrew the regulator to see how we could effect a replacement. We would not expect that the regulator is too unusual, and you may be able to install a replacement. The first thing to do is to remove the control panel cover and get a look… Read more »
Aloha. I have an old military compressor, probably 80 gallons or so. It’s set to shut off at 147psi and turn back on at about 117psi. The tank has its own gauge, the regulator has a gauge and I put one after the regulator before the tool’s hose. I drained all the air out of the compressor and the hose end, unscrewed the pressure set knob all the way to the stop and filled the… Read more »
So I’m not much a DIY’er, but a couple Christmases ago my father-in-law bought me a Porter Cable 150 psi air compressor. Embarrassingly I just tried to use it for the first time today to air up a low tire on my car. I followed the instructions about attaching the tube and proper fitting, turned the regulator pressure knob fully counter-clockwise and turned it on. When the tank air pressure reached about 140 psi it… Read more »
Please shut the regulator off, run the compressor until the tan pressure reaches the cut out setting and the compressor stops, then dial the regulator back up. Monitor the TANK air gauge. How fast is it dropping? In order for the compressor to start, assuming the pressure switch is working properly, the tank pressure must drop to below the cut in pressure setting of the pressure switch. If the tank pressure is dropping while you… Read more »
I have a ABAC Pole Position Compressor 2HP / 24Lt – It is just a cheap model and fairly old. My question is regarding the Pressure gauge and regulator – this seams to be 1 unit on my item and only has 1 gauge which shows the pressure of the tank, The regulator only has numbers round a twist knob however it has come loose and so the numbers do not match the reality i.e.… Read more »
We tried to find an image of the compressor to better understand the problem. No luck, we’re afraid. Simply put, air from the compressor tank flows to the base of the pressure switch so that it can “read” the tank pressure and turn the compressor on an off as needed. That plumbing typically has the tank air gauge installed as well, so the compressor user can monitor the air pressure in the tank. The air… Read more »
Hi thanks for the reply I think it makes sense. To help here is picture of the offending item.
After much searching found this which is the actual part.
I think it is time to replace 🙂
Yes, it’s easier to acquire the exact same item. Yet you can also acquire a regulator like this, Karl, which will do the same job and you see the pressure setting on the gauge which might be easier.

I have a Craftsman air compressor model number 919.167280. It has pressure regulator D27253. The nut on the inside of the regulator has stripped out and now the regulator won’t keep pressure. Does anyone know of a place to get a replacement nut for the regulator. I know they are most likely disposable, but a new regulator is around $60 and I can’t bring myself to pay that when all I need is a $.05… Read more »
Chad, when we look at the image of your model of Craftsman air compressor, it seems clear that what your compressor needs is a low cost regulator, to replace your damaged one, since parts for mini regulators are almost impossible to find. The replacement air regulator need not be an OEM regulator which, you say, will cost $60. If you Google mini air regulator, you will find many sources for one that suits your compressor,… Read more »