Is my pressure maintaining valve broken?

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Andrew, my Junior II does not fill like you describe, it starts slow then air comes out in one constant stream.
I should have mentioned this is exactly how mine works now. Starts slow, hits pressure and then comes out in a much higher constant stream.

Previously, no air would come out at all (none, nada) for 30 seconds or so. I then get a bursts of air as the pressure builds up to 150bar and drops below 150bar.

I really think your PMV may not be working correctly.
 
The PMV I have consists of a ball bearing held against a seat by a spring and is easily rebuildable. I have seen a suggestion that before rebuilding it you can sometimes correct a leak by removing the spring and using a suitable brass drift or rod against the ball and tapping it with a hammer to seat the ball against the seat. Might be worth a try if it is of similar design.
 
Michael, I'd be concerned that your PMV is not working correctly.

From the Junior II manual


It would take some time to build up the pressure to 150bar so there should be no flow at all until it reaches 150bar.

By the way, Cody's PE-100 works exactly as mine (used to).



I have but given the PMV works at 150bar, that's no easy way for me to blow >150bar back through the valve.
That is exactly how mine works, nothing then air and then a constant flow. I did not word it correctly first time I posted. It does not come and go like the PE100 seems to, obviously a different procedure.
 
Can you post a pic your model PMV?
 
I have a Cornelius 3500 compressor with a Lawrence Factor PMV and it acts exactly like what was previously described- I have it set at about 1600-1800psi and it will build pressure and begin to cycle/ purge without a steady flow until it reaches around 600-700psi and then it appears to begin to allow pressure to flow non-stop. When depressurizing it will hold at the 1600-1800psi range as it was set for. Not sure if this helps anyone else.
 
I managed to get it apart and it is basically a piston and spring. There was nothing I could see that could be adjusted or serviced.

IMG_0342.jpg


I already decided to replace it and would have already if Bauer weren't doing a stocktake. They are only 30 minutes from my house and have it in stock but it looks like I won't be able to pick it up until next week.
 
If you have decided to replace it anyway and have to wait a week why not try lapping the piston and the seat that it bears against.
 

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