DevilBiss Pro 4000 - air leaks out until it kicks on at 95 psi
by Arlan Vierra
I have an old DevilBliss Pro 4000 3.5hp with a 30 gallon tank.
Parts don't seem to be around for it. It needed a new pressure switch and a shroud. Can't find a shroud for it. I will probably fabricate one out of sheet metal.
I put a pressure switch on it and the switch has a by-pass. It must not have a check valve since the air leaks out until it kicks on at 95 psi.
Do you have any ideas on this? I don't know if there is a check valve in the manifold and its stuck or if it should have a switch without the by-pass.
1) Why do you need the shroud? If you don't need it, don't put it on.
2) Don't quite know about the pressure switch bypass, I suspect that it's for the unloader valve.
3) Usually the tank check valve is where the line from the pump enters the tank. It does sound like your check valve is leaking. Is there not one there?
devilbiss prfb5020vp - does it stack up?
How does this compressor stack up against other similar units?
Hi Jim. That's a difficult question to answer, given the broad range of comparably sized compressors out there, and the general nature of your post.
Stack up how? Compressed air production? Price? Expected life? Warranty? What's available where you are? Too many variables, Jim.
See how to select from the nav bar for pages providing tips on all the questions you'll want to answer for yourself.
And, if someone out there has this air compressor and wants to offer Jim some advice, please chime in.
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What is value of 2001 Devilbliss pro air 2 80gal 650 hp air compressor
hello, I have 2 of these air compressors and I'm trying to sell them. my business has failed and I'm trying to sell my shop tools. any help about the value would be appreciated. they are in excellent condition. thank you, Albert
Look on line and see what others are selling for. Check the industrial journals on line too.
Essentially they are worth what people are prepared to pay.
I have added your post and others may contribute. It would have been better for you, I think, if you had added some contact info in here along with your location as anyone interested would need that info.
Devilbiss Model 445 Leaking Air Back through Compressor
(Calgary, Alberta, Canada)
Model 445 15 HP .
Compressor is leaking back through the compressor head. You can here the leak, and the pop-off pressure valve will trip on the bottom of the cylinder. Its not bad yet just started. Any help would be great.
This is the twin cylinder model, and as such, should have a PRV in the line, or plumbed to the line, between the cylinders.
If it is the PRV popping off between cylinders, or at the second cylinder, then I would suspect that the valve(s) on the second cylinder air not working properly, impeding flow, and causing an overpressure in the line, popping off the PRV.
If you can feel or hear air bleeding back out of the air intake, then the valve(s) there are failing. Air should only be pulled in, not allowed back out at the intake.
Maybe it's time for a replacement valve job for both cylinders, and if you do, make sure you replace any seals and gaskets at the same time to elminate another tear down in the not too distant future.