Peter that is the regular aqua-enviroment PMV, with a fixed set point..I do not recall ever seeing one that was not adjustable with the exception of that one.
I will not enter into the debate about the quality of that particular valve has it has been debated endlessly, Ray sells it, Ray sells the compressors.
It is inexpensive, it works..any thing will work a heap better then nothing.
Also, I linked all of that info to this gentleman, if he had so chosen he could have learned all of that himself and if he had P.M.ed me I would have sent him all of Steve Burtons stuff, even discussed where Steve may be off the rails a little bit...Not that the guy is not sharp, he is. Also I would have been happy to send on copies of a huge library of reference material I have acquired. He chose not to take that road, which would have required a bit of work. Maybe given him some real insight into what he is doing, not just wasting his filters..the whole process. He chose not to take me up on the offer, I think passing info like this on to people who are not prepared to learn, well we do not know what they are gonna do with it, and the simple fact that that a national manufacturers rep told him to do something, yet he knows better...I do not think it wise to enable somebody in a situation like this.
If you cannot tell when your PMV is releasing, it looks like you asked this question....you may have a defective pmv....a very simple check.... start compressor, open your fill whip, observe the pressure when the whip starts to release gas...problematic if your final pressure gauge is on a single whip, but that is easy enough to work around.
Set point is 1900 psi.
Item # 1310, 1310 Back Pressure Regulator On Aqua Environment Co., Inc.