Great white tank & fill station over filling.

[Phil.Probe]

The last few times I've filled my PCP pistol from my tank, I shut off the valve @ 3,000 psi, but the pressure continues to build to about 3,400 psi, even though the valve is 100% closed. It wasn't doing this a few days ago. Any ideas what could cause this?

 

[Gerry52]

I'm assuming you mean you shut off tank when guns reservoir reaches 3,000psi but it continues to climb. Is that correct? Don't forget that the gauges on all that stuff, by nature, are imprecise. They JUST give us an approximation. Try shutting off tank at 2800psi & see what your gun reads after.

 

[Asher]

I've had this problem but only in the cold

 

[Phil.Probe]

I'm assuming you mean you shut off tank when guns reservoir reaches 3,000psi but it continues to climb. Is that correct? Don't forget that the gauges on all that stuff, by nature, are imprecise. They JUST give us an approximation. Try shutting off tank at 2800psi & see what your gun reads after.

Yep, you understand the problem correctly. I do try to anticipate the lag and shut it off early, but I didn't have to do this in the past, so I'm wondering what's going on.

 

[Phil.Probe]

I've had this problem but only in the cold

The temps were around 60 deg. I haven't had problems in the past at those temps, so I don't think it's related to that.

 

[Gerry52]

Wish I could think of something but I've never had a gauge creep UP after filling. Is it possible something is restricting air flow into gauge?

 

[Scotty1]

I wonder if you have a slower filling foster fitting, and it’s still equalizing after you close the valve, so the fill line has higher pressure than the gun until it doesn’t. Hard to word…

 

[Phil.Probe]

Sorry guys, for some reason, my last response didn't post up.

To answer your questions re restrictions, my fill whip is very narrow gauge. Also not sure if it matters, but I'm reading the pressure on the fill station gauge, not the gun. I've since filled up the gun a few times and the problem seems to have gone away.