Preventing freeze free flow?

[Greendiver]

Believe me, I'm looking forward to the day I can buy a dry suit!

 

[elan]

Ok looking for some advice from some of the more experienced members of the board...
A couple of days ago I did a shallow dive in fresh water. Water temp was 33f and air was 25f. Entered from the shore without breathing on my regulator until I had submerged, immediately after the first couple of breaths my second stage began to free flow. I surfaced and turned my air off and hung out for a couple of minutes. Turning my air on again with the regulators submerged everything was ok so we continued with the dive... A couple of times the regulator would freeze up and free flow. While not the solution I would prefer, I kinked the hose for my second to stop the flow, sort of feathering it to breath. Each time after 15-20 breathes the flow would stop and normal operation would resume. I believe it is the 2nd and not the 1st freezing as my octo didn't free flow, but I didn't breath off it either. And, the flow wasn't massive, on inhalation there was no exhaust.
All this info leads to this...
Is there anything that I can do to minimize or eliminate this as I won't / don't trust this as is for anything deeper than snorkeling depth dives. My regulator is an Aeris atmos lx. I realize that "...just get a new cold water reg set!" is the first reaction most will have. But, is that the only answer?
Enlighten this rookie, thanks!

Most likely that's the second stage acting up.

Not all second stages can handle that temperature. I have Aeris AT400 Pro set and it is detuned all the way down with IP set to 125 psi. It was working well in 40F+ water for many dives. But it failed the test in 36F - second stage started flowing after 3-4 breaths.

 

[DA Aquamaster]

I used to use Mk 17's ice diving in 33-35 degree water at depths down to 90-100' (so high flow rates as well as cold temps) along with D400, X650 and G250 second stages. All worked fine with no freeze flows, at least for the average 30-45 minute ice dive. I have also used those same regs on deeper dives (150') in 35-39 degree water with no freeze flows on much longer divers (up to 2 hours).

As noted above, do not use, test or breathe off the reg above the surface of the water. Check it at home if you must, but leave it alone pre-dive so as not to supercool it before you get it wet. Do not inflate and breathe at the same time, but also adjust buoyancy in short bursts rather than in one long blast on the inflator.

Never ever use the purge and be advised that taking the reg out of your mouth and letting it freeflow lets in cold water and supercools the metal parts of the valve. The result of the two at the same time is often a freeflowing second stage when a piece of ice forms and prevents the valve from closing.

Low pressure tanks also result in less adibatic cooling than high pressure tanks.

 

[Greendiver]

What about keeping your regulator outside prior to the dive? In my case above, the reg set had been kept inside the house and then in a warm car for about 2 hours and within 20-30 minutes in the water.

I didn't breath off of it until underwater but that is a tough habit to break in the cold water! Just seems natural to check both 2nd's when suiting up!

 

[meesier42]

breathing off a reg on the surface isn't really going to do anything. go ahead and check them.

I have a feeling that you have a couple of issues.

First- your reg is probably tuned to breath with minimum cracking effort, which means that it takes very little to get a free flow, so detuning should help
Second- its possible that your air isn't as dry as it could be. Given the single breath to freezing, I think this may be the case.
Third- this reg is really not designed for cold water performance. even though it has what Aeris calls an environmental seal, its a really shoddy one that at rebuild time most all of them show evidence of leakage.

my end advice, is that if you intend to dive extensively in cold water that you get regs designed for it. Zeagle, Apeks, and Poseidon all make fantastic regs that perform flawlessly in cold water.

 

[elan]

breathing off a reg on the surface isn't really going to do anything. go ahead and check them.

This is correct if the temperature on the surface is way above 0C. If it is close to that the reg can start flowing right on the surface and the moist air can lock the second stage open.

 

[elan]

What about keeping your regulator outside prior to the dive? In my case above, the reg set had been kept inside the house and then in a warm car for about 2 hours and within 20-30 minutes in the water.

You should be fine in that case. The bad scenario is when you bring your tanks from the outside to inside get the condensation in the valve and then install the regulator. In such a case the moisture is trapped in the valve and will go into the first stage.

I usually do things in this order Have the tanks and the regs inside inside warmed up. If I still have the condensation in the valve I wipe it out and blow the valves, Then install the regs and make few breaths. After that you can do anything you want - the air isd dry and the moisture cannot get in.

When on the dive site if the temperature is below freezing or close make sure your second stages do not get wet before you submerge.

when submerging I have both regs in the water then do the kissing water for half a minute while breathing of the backup, replace my mask and we go down.

At the end make sure the moisture cannot get into the first stage or all the sealing will not matter as the moisture in the valve can cause the 1 st stage freezing.

 

[elan]

I didn't breath off of it until underwater but that is a tough habit to break in the cold water! Just seems natural to check both 2nd's when suiting up!

Just purge them slowly

 

[baitman16]

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What was your ip pressure there are several factors that could have caused this. Are your reg's tuned for cold water,where did you get your air,is it filtered good so many possibility's but i think tuning is your first step. Tuning for cold water is a must. We do free checks at Advance Scuba in Holland before we do any cold water dives like the New Years Day dive. I was using a Zeagle flat head six with a aga mask so i had to breath above water and i had no issues. Also if your dive shop offers hyper filtered air it is worth the xtra buck to eliminate that factor. I take my flat head sixes to 300 feet for over two hours in 30plus deg water and they work great.

 

[DCBC]

My regulator is an Aeris atmos lx. I realize that "...just get a new cold water reg set!" is the first reaction most will have. But, is that the only answer? Enlighten this rookie, thanks!

Often relatively new divers consume air faster than more experienced divers. This can affect the chance of free-flow i.e. the volume/demand of air required to be delivered by the regulator. For this reason, I don't dive under ice without a redundant air-supply. Using a buddy's octopus compounds the chance of freeze-up; again increased demand/volume in cold water. So my first recommendation is that you lower your gas consumption through experience before diving in cold water. That's one precaution you could take to lower the chances of free-flow.

As I assume that your regulator is tuned properly (have this checked at the LDS), I would not recommend lowering the IP on the regulator. I would simply refrain from diving in cold-water with the regulator you have. This may sound a bit harsh, but I support utilizing the correct gear for the job. Nothing against your reg (I'm not familiar with this particular model), but you can't make a deep diving reg out of a basic model and you can't make a dependable cold-water reg out of one that's not designed for this purpose. There are no short-cuts when it comes to diving safety.