IP creep

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elan

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Location
Toronto, Ontario, Canada
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I have a question, what is considered the normal range for IP creep, most of my regs have a recovery time (when the IP stabilises) within a second - two and then drift within about 6-8 psi. One piece recovers to the same within 3-4 seconds and creeps at least 15 more psi within next 2-5 mins. I did not wait longer but I think it's time for the seat to see the day light :)

The reg is Zeagle Flathead VI

Thanks a lot.
 
To me any creep above a little settling (less than 5PSI in a few seconds) is not acceptable, but I will say that my MK10s, or at least one of them, will creep a few PSI if I haven't used it in a while. But 15 PSI over a couple of minutes is a HP seat failure waiting to happen. It's easy to miss too, because when you're diving you obviously breathe often enough to negate the effects of the slow creep.

When I rebuild a reg, I'll usually leave it pressurized for several hours after cycling it just to make sure there's zero creep.
 
Thanks halocline, seem to be the time for overhaul. Packaged it yesterday to drop at the service guy's
 
BTW, the creep you are referring to is actually pressure increase until lock up. I recently rebuilt our 4 regs. Each one would seat with a 4-6psi increase in pressure over maybe a minute until they locked up. After rebuilding them they locked up immediately. So as said above your reg are ready to be rebuilt.
 
BTW, the creep you are referring to is actually pressure increase until lock up. I recently rebuilt our 4 regs. Each one would seat with a 4-6psi increase in pressure over maybe a minute until they locked up. After rebuilding them they locked up immediately. So as said above your reg are ready to be rebuilt.

With the amount of creep he is talking about, I'd suspect it never locks up. Rather the IP just climbs until one of the 2nd stage downstream valves opens enough to relieve it. Since that may take minutes to happen, it may have no effect on dives. But such creep just does not heal itself and as the problem progresses (it does usually start out with just a few psi increase over set pressure and then lock up) and it gets to leaking after some wait time, the wait time gets shorter and the severity of the leak increases. IP creep to a higher IP lock-up is an indication of an growing problem. Some can be tolerated with no adverse effects. With my balanced piston 1sts, I set IP on the low side (125 to 130) and monitor closely once some creep appears. I usually service by about 10 psi.
 
Good to see folks owning and using an IP gauge :)

I look at it as part of my setup routine.
 
With the amount of creep he is talking about, I'd suspect it never locks up. Rather the IP just climbs until one of the 2nd stage downstream valves opens enough to relieve it. Since that may take minutes to happen, it may have no effect on dives. But such creep just does not heal itself and as the problem progresses (it does usually start out with just a few psi increase over set pressure and then lock up) and it gets to leaking after some wait time, the wait time gets shorter and the severity of the leak increases. IP creep to a higher IP lock-up is an indication of an growing problem. Some can be tolerated with no adverse effects. With my balanced piston 1sts, I set IP on the low side (125 to 130) and monitor closely once some creep appears. I usually service by about 10 psi.

Yeap I did not wait until it locked up - it went over 160 and I just stopped it as it really looks like an issue.
 
I once rebuilt a Zeagle first stage that had a slow creep that I shut down when it got over to 180 psi. Turns out the body was cracked. I sent it back to Zeagle and they replaced it under warranty. Zeagles should have no IP creep at all. They should lock up immediately. The biggest allowable IP creep that I know of is on Poseidons; they call for a 1 bar (15 psi) creep after "lockup". Most all other manufacturers call for 1-3 psi creep. Truth of the matter is I don't like to see any creep at all, but sometimes it can't be helped (Poseidon).
 
You might have a problem with a bad high pressure seat in the 1st stage.
What tank pressure are you shooting to to regulator, and when was the seat last replaced?
Do you know what color the HP seat is?

The reg was new 2 years ago, never serviced and was laying in the closed for the last year. The pressure was about 1500psi. I do not know the color though.
 
https://www.shearwater.com/products/perdix-ai/

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