Free flow at 94' ffw

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Very well done for handling the situation and informing us about it!

It seems it took more than 6 minutes for the tank to drain. That's my estimate based on: 3+ minutes problem solving and ascent, 2 minutes SS, 1 minute further freeflow on the surface. Can you give us a more accurate figure?

In any way I am glad to know it is much more than the 2 minutes usually mentioned for 2nd stage/LP hose problems.

Thanks for sharing and welcome back :)

I started with a full 100 at just under 3000psi I finally downloaded my dive profile to look at exact times and rate of ascent and it took me four minutes to get to the surface from where I turned the dive at 94ffw it looks like I stopped my descent for about 20 seconds at that 94ft before going up so I am assuming that I spent that 20 seconds problem solving. My free flow started off slow and I'm not sure how long it took to reach full free flow but my guess was probably only 10 to 15 seconds my stop was a minute 38 I had been down only 7 minutes when I made the ascent so I had not used much air from the tank so it took about 4 and a half to 5 minutes for that tank to go from about 2700psi to 300psi obviously an 80 would go much faster so it depends on the tank you dive.
I remembered coming across this chart a few months back and found it interesting so I hunted it back up. I think this is for an 80 at 3000psi my time was a bit longer so obviously its not exact but it wasn't too far off from my experience.

pic_1_82625.jpg
 
Based on the description, I believe it was likely that it was the 1st stage that was freeflowing. It was just venting through the alternate.

Freeflows in cold water are not unusual and no reg is completely immune. Good on you for bringing a pony

LP shutoffs are IMO not a good thing. The way to resolve this problem at depth without ascending is to switch to a pony (or the other post, if diving twins) and shut the tank valve for the offending reg. If the freeflow is caused by ice, the offending reg will usually thaw out after a few minutes, and then you can switch back.
 
Treat Flow stops with caution. If it is the second stage that as free flowed, then shutting off the flow stop would be OK. However, if it's the first stage, the second stage acts like a pressure relief valve, closing the Flow stop, would result in a burst hose.

If you have 1 first and 2 second stages. Closing the lp to the free flowing 2nd would, if the problem is the 1st stage, result in the other 2nd stage free flowing rather than a blown hose.
 
If you have 1 first and 2 second stages. Closing the lp to the free flowing 2nd would, if the problem is the 1st stage, result in the other 2nd stage free flowing rather than a blown hose.

Yes - I'm too used to twinset and single regulators. However you look at it, it will probably make things worse, two 2nd stages free flowing rather than one.
 
Yes - I'm too used to twinset and single regulators. However you look at it, it will probably make things worse, two 2nd stages free flowing rather than one.

No, not realy.

if you close the ome that i free flowing you get one off two results.

1. it was the 2nd that faulted, you stop the flow.
2. if it is first stage creep, you close one, the other one starts to flow, you open the flowing one again and you are back where you started.

But what do I know, if my first starts to flow, the opv dump it out and i can use it as usual till the air runs out.
 
I'm curious NOT critiquing . Why wasn't breathing that freeflow reg for awhile an option ?
 
The freeflow was coming from my alternate. I was able to keep breathing from my primary like normal.
I think he meant to say that you may save air by breathing the freeflow reg.

IMHO it is not obvious to me that it will lead you to get more air time with the additional focus on breathing the freeflow reg.
 
A bit of a long read:
This winter at one of the local lakes I dive there was a truck with a trailer and snomobile that broke through the ice and sunk, furtunatly the driver and his dog managed to escape and walk to safety. My dive partner and I have been wanting to locate the truck and dive on it. We finally got the time to take my boat out and try to locate the truck with only a vague area of the accident. There were three of us that would be diving together, my buddy who is an instructor, me a dive master and another diver with less experience who is part of the local fire department dive team and a good diver. We spent about 2 hours with the sidescan but had no luck finding the truck on sonar.
We decided to make a dive in the area so that we could see what conditions we would be diving in if we were able to locate the truck at a different time with hopes of recovering the snomobile if we ever locate it. The bottom was about 120ffw.
The water in this lake is cold with a surface temp of 54 and drops quickly as you descend, my last deep dive in this lake was mid summer last year and the bottom temp was a balmy 37 degrees Fahrenheit. Drysuit and thick undergarments are a must as well as good cold water regs. I normally dive using my aqualung legend regs but on this dive I would be using my new OMS regs with about 5 dives on them.
We both dive similar setups oms backplate dui dry suit and pony bottles. We were near an island with a wall that drops from 15ffw to the bottom at just over 120ffw so the dive plan was to anchor the boat in shallow water then follow the wall down to the bottom check the conditions then work our way back up. The visibility was next to nothing and went black at about 30ft, nothing we haven't dove in before but we usually have better viz in this lake. My buddy was in the lead with the newer diver in the middle and me bringing up the rear we had to stay close due to near zero viz. Everything was going good on the descent and the lead diver stopped to check we were all good to keep going at about 75ffw. At 94ffw and still descending I got a blast of bubbles around my neck and face, damn a free flow, water temp was 43 degrees. I immediately started checking to see where it was coming from and went to a feet down position in case it was my drysuit valve I didn't want it going to my feet. Because it was around my neck my first thought was that my drysuit valve had malfunctioned and I was venting through the neck seal, I opened my shoulder dump all the way and unplugged my drysuit. That didn't stop it. I knew I'd have to abort the dive regardless and knowing that my dive partner had another diver with him I decided not to chase them down but to surface on my own. It took a few seconds to figure out it was coming from my alternate I wear on a necklace around my neck I even took my primary out to make sure it wasn't coming from there. The alternate is the last place I expected a free flow because that's always in predive and detuned with the control knob to be tight to breath through to keep it from free flowing on the surface. The water was black so I kept an eye on my computer so I didn't surface too fast and kept checking my spg to make sure I still had air. My primary was still breathing just fine and I had my pony ready to go just in case I needed it. I made a two minute stop all the while messing with my secondary to try and get it to stop blasting my air out, it didn't stop free flowing until I had been on the surface for at least a minute tank pressure was about 300psi
Luckily it happened on the initial descent and I had a full 100 to start with. Like good divers my buddies were on the surface about 4 minutes later after they made a 3 minute stop.
I have gone over the scenario several times and had a discussion with my dive buddy and I don't think I would have done anything different. In clearer water I could have signaled a problem but due to the black water and knowing I wasn't leaving him alone I decided to abort alone knowing I had redundant gear.

A few takeaways, I have been on a few dives where things have happened and have acted accordingly but was happy with myself when I had an emergency happen to me. I kept cool knowing I had an extra air source if mine completely failed.
OMS had issues and recalled all their regs due to free flow problems a few years back but this was the new and improved regs. You'll never catch me with oms regs in my mouth again, I do love their other gear though.
A pony bottle is a must for me now on deeper dives and I'll always have it by my side, never thought I would need it but certainly glad I had it.
I'm sure there will be divers armchair the heck out of this but I was there and made the decisions I did and would make the same decision in the same situation. Like an airplane pilot will tell you, any landing you can walk away from is a good landing. Any dive you can walk away from is a good dive and this was a good dive. If nothing else it was a good training dive.
ummm.. a first stage freeze will make whichever second stage that has a lower cracking pressure freeflow. Frankly when I dive in water that cold I set my IP lower to around 120 as well. The predive and detuned will have zero bearing on freezing or not (1st or 2nd stage) so not sure where you got that idea.

Thinking it was your drysuit first,.. is a bit weird to me, it would have been my last thought as if it went I would immediately feel my buoyancy change. Please don't take this wrong, that you felt it could be and you didn't notice any change in buoyancy.. any chance you dive quite overweighted? By the way, going vertyicle should never be part of the solve a problem process IMHO
 
ummm.. a first stage freeze will make whichever second stage that has a lower cracking pressure freeflow. Frankly when I dive in water that cold I set my IP lower to around 120 as well. The predive and detuned will have zero bearing on freezing or not (1st or 2nd stage) so not sure where you got that idea.

Thinking it was your drysuit first,.. is a bit weird to me, it would have been my last thought as if it went I would immediately feel my buoyancy change. Please don't take this wrong, that you felt it could be and you didn't notice any change in buoyancy.. any chance you dive quite overweighted? By the way, going vertyicle should never be part of the solve a problem process IMHO

As far as detune and predive in my alternate I do that so to help it keep from being too sensitive but only on my alternate, if I am not understanding what you are trying to say here, my apologies. I am not a reg tech and don't set my own IP's however I have thought about getting the tools and training in the future.
My weight is good, I dive a couple pounds over weight 2-3 but for me I like it because I don't like to be on the raged edge of weighting when I am in bulky undergarments but that's me. I was in black water so I had zero visual reference to my surroundings and really never would have expected my alternate to be the one that went into freeflow so when I felt air coming from around my neck my first thought was that it was air coming out of my neck seal. The reason I went vertical was that if it was my drysuit inflater malfunctioning it would continue to leave my neck seal and not fill my feet up with air and I end up breaching the surface like a backwards whale from 100'. As far as feeling a change in buoyancy I suppose its possible but with a full on freeflow blasting me in the face it was a bit disorienting and I was doing my best at problem solving and trying to calmly but quickly eliminate the possible issues at hand.
 

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