Re: It's not the high pressure line you need to worry about.

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Posted by Chuck Tribolet\ on October 03, 2006 at 14:53:19:

In Reply to: It's not the high pressure line you need to worry about. posted by Chuck Tribolet on October 03, 2006 at 12:10:00:

Here's what I posted on UW photo when I ran the experiment. It
was 320 PSI/minute for the HP port, and 3560 PSI/minute for
the LP port.


> Your post prompted me to run an experiment. I took a full
> AL80 and I put my Atomic Aquatics B1T2 on it. The Oceanic
> DataMax Pro said 3090 PSI. I closed the valve, drained the
> regs, and removed the air integrated computer. I opened
> the valve on the tank all the way for two minutes, making
> loud hissing sounds as it vented through the HP port,
> closed it, and reinstalled the computer. It was down to
> 2350 PSI. That would be 6.75 minutes to drain to 500 PSI
> assuming a constant flow rate (and the flow rate would drop
> off somewhat as the pressure dropped off, so it would be
> more than 6.75 minutes)
> First stages have a small orifice under each HP fitting for
> exactly this reason. Maybe your rental reg was so old it
> didn't have one, or some idiot had drilled it out, or
> something.

> I decided to run a second experiment, this time on the LP
> side. Same AL80, at 2450 (it had a day to warm back up).
> I pulled the octopus off and opened the valve. It made a
> huge noise (every dog in the neighborhood started barking,
> including both of my Newfies), tried to knock the tank
> over, and was generally much more dramatic. I could watch
> the pressure on the gauge, and quickly figured out that
> this better be only a 30 second test. After I closed the
> valve at 30 seconds, it was down to 670 PSI.

Follow Ups:
  • Hoses Jeff Shaw 21:22:06 10/03/06 (1)
    • Re: Hoses Divebum Don 07:09:26 10/04/06 (0)

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