IDi Seaira Try metal freeflow

[Nooreck]

Hello everyone ?!

We finally managed to go out and do some ice diving this season after a long anticipated date....

Making the story short, I own the Idi seaira Try-Metal regs from IDi and so far i never had any problems with it even diving relatively cold waters but this time I dove in 3-4 degree temp. and to my surprise I got a free flow under 15 feet.

Came out I adjusted the purge presure valve in it to conpensate the pressure and same thing.

Surfaced again... I tourned the adjastment all the way down, so it was really difficult to press the reg to purge it, I took it down to 25 feet and after maybe 5-8 min the reg stardet to freeflow again.
So I gave up on those regs for that day... I used some old sherwoods and I had no prblems with them...

doeas anyone have any idea what that could be with the IDi's
I am considering the intermediat pressure adjustment but I am not too sure if this is actually adjustable without sending them to the factory ????

i appreciate any feed back.... I would really hate to be buying another set of regs ????
Thanks

PS; here are some pics form that trip, I 'v got the blue gloves.
http://tintin.renouf.com/gallery/Diving

 

[pufferfish]

Nice pics Nooreck. There are lots of factors which can contribute to a free flow or freeze-up, but reg design and proper cold water handling are probably the big two. I see that IDI reg is a balanced piston and I suspect like the Scubapro regs once you are below 5 C water temp you might get a freeflow one day while the next you don't which is no way to have to dive. You are better off with a dry sealed first stage in those ice conditions or as you found out with a Sherwood dry bleed system.

Things you might try in the future though to see if the reg might function better in those conditions:

1. Make sure your tank air is very dry. Should have a dewpoint of at least < 60 C (< -75 F) for ice diving

2. Try and use low pressure tanks as I see some high pressure tanks in your photos. The higher the pressure differential in your first stage the greater the cooling effect there and greater chance at initiating the freeze cycle.

3. Keep your regs and tanks warm until you must use them. It your tank air is starting out at +20 C and not -5 C the adiabatic cooling in the first stage will be less. Same principle for the reg and its metal components.

4. Don't breath off the reg or fill your BC or press the purge at all before diving. All these things lower the temp in the first stage and in the case of the second provide moisture to freeze. Don't start breathing off the second until your head is under the water (some folks here say it ok to inhale but not exhale which is probably true)

5. Get your intermediate pressure checked by your service tech. It should be turned down to the lower range. Most freeflows are first stage issues as the temp drops across the second stage are not as great as in the first stage. Changing to a lower pressure tank will make far more of a difference than adjusting your second stage but remember every little trick will help and prevention of freeflows is the key.

6. Try not to breath and use inflator at same time as these high flow rates cool the first stage quickly. In the same breath try and maintain low air consumption rate which is always harder when your privates have disappeared because of the cold

7. Be very careful when switching tanks on the second dive that a drop of water is not sitting near the inlet filter as any moisture that gets in here will freeze in an instant. On multiday ice dives it is best to leave the filter cover off overnight to allow any moisture here to evaporate.

I am sure I forgot a few but if those suggestions are unsuccessful you will likely be retiring that reg for use in Cozumel or Brockville only. If so I'd start looking at a diaphragm first stage from Apeks or Aqualung or why not just stick with your Sherwood for the real cold stuff if you are not diving too deep. Good luck and let us know how things turn out.

 

[pufferfish]

This was posted by Warmwaterdiver on the thread below which shows very nicely the effect of tank pressure on the cooling in the first stage.

"OK, I'm new to this board, and new to tech diving, and haven't done "cold" water diving, but I'm not new to gas laws or thermodynamics. So, I used some software to calculate temperature drops solely on pressure drop (not flow rate) in an adiabatic expansion of bone-dry air. I used 15 PSIG for 33 feet depth, 125 PSIG for second stage inlet pressure, and a gamut of first stage inlet pressures. Results were there is only 3 degrees Farenheit drop in temperature in the second stage from intermediate supply pressure of 125 PSIG for adiabatic expansion. Of course, the deeper one would go, the lower the difference in these two pressures (discounting the newer "overbalanced" diaphragm first stage designs), and so the lower the temperature drop from adiabatic expansion would occur.

However, there is certainly a significant drop in temperature in the first stage if this system is treated as an adiabatic system. At 1800 PSIG tank pressure (older steel tanks), to the 125 PSIG intermediate pressure, there is a 36.5 degree F temperature drop. For 2400 PSIG in the tank, there's a 46.5 degree F drop, for 3000 PSIG in the tank there's a 58.0 degree F drop, for 3500 PSIG high pressure steel tanks starting off there's a 60.3 degree F drop, and for 4350 PSIG tank pressure, there's a 67.3 degree F drop.

So, if the regulator first stage is viewed as an adiabatic system, one risks reaching 32 degrees F in a first stage with 90 degree F 3000 PSIG tanks on the first breath!

The conclusion is these systems are far from adiabatic, and in my opinion, are attempted to become as isothermal a system as possible. Has anyone had freeze-up in their first stage with 3000 PSIG tank supply pressure and tank / water temperature around 90 degrees F? How about 70 degrees F? I haven't seen a report of such posted."

http://www.scubaboard.com/showthread.php?t=47081&page=1&pp=15

 

[Nooreck]

Thanks pufferfish, from what I hear sound like I will have to spend some hard earned dollar agian eh ??? well now I know for sure what to go for... APEX sealed.
Boddy of mine has the ATX200 and all 3 dives he did without any problems so this looks like a really good system to go for....I'll wait and see what will happen after this saturday, we are heading out one more time and probably the last for this winter....if the temps will continue to hold like this ???

and yes both of my tanks are HP's that could be the reason as well..

IDi is recomending some kind of boot cover for the first stage I wonder if that would help...we will see , I have my regs serviced as we speake....what would be the recomanded intermediate pressure for this kind of environment ???? 120/ 130 maybe ????

regarding the breathing?? yes I didn't use the reg untill I was under the water but that didn't help at all....

So as the conclusion this is going to be the last cold dive i will probably do, so even if the reg is still going to flow i might keep it untill the next winter, and for the sumer it should be all right.

What bothers me the most is that fake advertizing everyone is using ???in there specs, but I shouldn't really judge it yet.

I'll let you know after this saturday, and perhaps if you are in the area we are heading to Simcoe, in Barrie of Esna Rd. down to the park by the lakeshore rd.

Cheers and thanks for the info...

 

[Nooreck]

Warmwater diver thanks for all that tech info on the pressures it is helpfull for sure to actually see the real difference in temps drops... I must say you know your stuff..

I will post the certificate reference of my reg soon for the referance...

thanks a bunch.

 

[Nooreck]

Ok everyone I found the certificate and this is what the test posted.

TYPE seaira tri-metal/ Bras
INTERSTAGE PRESSURE 8.2 bar.g ( surface/static )

Condition of test
AMBIRNT TEMP. 23.0 c
HP SUPPLY PRESSURE 52 bar.g
TIDAL VOLUME 2.50 litre Breath Rate 25.24 bpm
VENTILATION RATE 63.1 lpm

Results
INHALE PRESSURE 4.99 mbar (Limit=25mbar)
INHALE POS PRESSURE 1.30 mbar
EXHALE PRESSURE 8.24 mbar (Limit=25mbar)
EXT WORK OF BREATHING 0.79 J/L (Limit=3.0 Joules/litre)
POS INHALE WORK 0.01 J/L


Can anyone refere some feed back to this please ????

Thanks

 

[pufferfish]

I am not an expert on this stuff (try Greg Barlow who used to do these tests for Rodale's) but that looks like a dry breathing simulator test which isn't very helpful other than to say it breaths quite nicely on a bench out of the water at 23 c and 1 atm. Not a very useful test.

Rodales to their credit is now doing wet breathing simulator ANSTI testing and this is a more useful test as they test the regs at four different depths and two different breathing rates. You can read about their most recent tests here
http://www.scubadiving.com/article/0,7424,2-0-0-635-6-3X6X9X15X21X25X28X29-9,00.html

Unfortunately though as you have found out these tests still do not address the issue of cold water performance and most of those simulators can only get the water down to 40F which is still the bottom end of 'warm' water here in Canada. Your comment about false marketing is very true. Many reg manufacturers advertise their regs as for cold water but when you read the fine print they tell otherwise. With the Scubapro MK25 they state it is "designed to provide resistance to freezing in accordance with the EN250 for cold water performance at < 10C or 50 F." What this probably means is they have tested it at 9 C and it works fine here which is certainly does but at 0 C under the ice that is a different story.

For true cold water performance data unfortunately there is not very much current data out there. The only people who do cold water bench tests and real diver tests are the Navy and researchers from McMurdo Station in the Antarctica. There has not been much testing for a decade so most of those regulator recommendations are quite dated. One of the researchers though has said that some new under ice tests may get under way in the next year or so but as usual research money is tight to do this sort of testing.

So what is one to do? Well you are doing what you have to do. Listen to the people who are already out under the ice and see what regs they are using. Basically you have to do your own testing and see what works and doesn't work. You will probably come to the conclusion like many others before you (and yes more hard earned $$ to spend) that for true cold water performance stick with a diaphragm reg. You can put on boots, silicone, alcohol in your first stage but why bother when there are excellent dry sealed systems out there that work. I think you will find that your fellow divers are using one of the diaphragm regs from Apeks, Aqualung, Atomic, or Posiedon under the ice and you will likely be switching too

Just curious in the documentation that came with your reg what do they say about cold water diving? Do they specify a temp when that boot should be installed? Also what country is IDI from? Notice a lot of the best cold water regs are from countries where they actually have well, cold water!

 

[Nooreck]

Thanks for such a quck reply...to answer you questions IDi is from Us California, owner originated from germany, worked with scuba pro on designing the jet fins, than moved to his own scuba gear business, they were arround since quite some time now, but no ice there..LOL and not much info about the cold water diving eather....
I read somewhere that dive rite is using simmilar components as IDi. Only thing mentioned was that IDi was one of the regs used to divie down to britanica the sister ship of titanic...,so another marketing gimick maybe....

The info on Roadel's site regarding that reg is pretty impressive,

Tester’s Choice again and again!
Tech and sport diving, a proven performer. A high performance balanced, super flow-thru piston brass/titanium first stage. 2 High pressure ports and 4/5 low pressure ports. Metal parts are chrome plated 316 stainless stell (piston). Re-designed piston allows for better heat conduction on the internal parts for cold/ice water diving. Teflon filled/Viton o-rings. For continuous cold/ice diving an ice-breaker boot is available, however, not always needed.

but like you said, no one is actualy testing these in the arctic environment to begin with. What would you like ??? to be send down to antarctica to freez up your loved ones or somewhere down south and do some fun test dives on a gear....of course down south...so we cannot relay on this info at all. right ???
But anyway I will wait and see if the service will help this saturday, untill than I should postpone my judgemental thoughts.

Cheers

 

[Nooreck]

Ok guys I just picke up my regs from service and appearently the main seal in it was kind of distorted so I had it fliped over....we will see if this helps, pressure was dropped to 120, as well .....that's all I know so far... tomorow is the day...

Cheers

 

[Nooreck]

Ok I'm back from the trip and quite dissapointed...........
My regs after being serviced and having the Embiant Pressure dropped to 120 did as a matter of fact freefllowed again, the water was 2-3 degrees Celcius....and I am really dissapointed in them thank god I didn't get this free flow on forest city wreck 160'

So anyway looks like I'll be getting my self a set of apax, seemed like it was performing the best out there ???? or AQ supreme LX we'll see....

To conclude this I will say this eather IDi is not up to what they claim or simply I managed to end up with a faulty unit......

Oh by the way lake simcoe was bad this weekend... Vis was 2-4 feet sureface -10 in the wind was the killer and the ice must of started to melt quite a bit since last time...

Cheers