Anti free flow device

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soggybadger

Contributor
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Location
United Kingdom
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Hi guys. I just wanted to ask if anyone has used or is using an anti free flow device and if so do you rate them. I ask as the wife is interested in getting one because she has non cold water regs and wants to occasionally dive cold water but not often enough to justify new regs. Thanks.
 
How cold are you planning on diving? Have you had free flow issues before?

I dive coldish water at times (5 degrees C is the record). I don't have cold water regs or anything and haven't had any issues.
 
Be careful. If the 1st-stage ices and jams so that the interstage pressure builds up, the 2nd-stage will freeflow. If you insert something in the pathway of the air to stop the flow, where is the pressure going to build? You don't want 3000psi in your medium-pressure interstage hose! The air has got to escape somehow. The freeflow is acting as a safety valve.
Better still - get some cold water dive training. People in Scandinavia manage to dive in Winter with all manner of regulators.
 
How cold are you planning on diving? Have you had free flow issues before?

I dive coldish water at times (5 degrees C is the record). I don't have cold water regs or anything and haven't had any issues.
Only UK cold about 6-7°c and the wife has had free flow issues before even using newly serviced cold water regs. thanks.
 
Only UK cold about 6-7°c and the wife has had free flow issues before even using newly serviced cold water regs. thanks.

Unless she's putting a lot of air into her drysuit or BCD in a short period of time, I wouldn't think this is a temp issue. Have someone check the intermediate pressure from the first stage and make sure it is correct for the second stage...
 
Be careful. If the 1st-stage ices and jams so that the interstage pressure builds up, the 2nd-stage will freeflow. If you insert something in the pathway of the air to stop the flow, where is the pressure going to build? You don't want 3000psi in your medium-pressure interstage hose! The air has got to escape somehow. The freeflow is acting as a safety valve.
Better still - get some cold water dive training. People in Scandinavia manage to dive in Winter with all manner of regulators.
Thanks for the reply. So basically could be dangerous with a first stage problem and pointless with a second stage as you would just switch to your alternant. The wife has only done cold water dives to date but doesn't plan on doing many more.
 
Unless she's putting a lot of air into her drysuit or BCD in a short period of time, I wouldn't think this is a temp issue. Have someone check the intermediate pressure from the first stage and make sure it is correct for the second stage...
Carry and use an IP gauge and that holds steady every time. Also had her regs serviced again after she had three ff on three consecutive dives directly after having them serviced. I now have them and never have a problem with them. Not to sure why she has had this problem but the main question was whether a free flow device is worth the expenditure and so far we have a resounding no. Thanks.
 
@soggybadger what regs are they and what is causing the freeflows? sounds like a second stage issue
Aqualung titan first and Arctic second or Hollis ds something or other. both superb cold water regs in my very limited experience that I have used with no issues whatsoever down to about 40m with a temp of about 4°c . I'm using them in my profile pic.
 
Aqualung titan first and Arctic second or Hollis ds something or other. both superb cold water regs in my very limited experience that I have used with no issues whatsoever down to about 40m with a temp of about 4°c . I'm using them in my profile pic.

I really don't like putting inline shutoffs on primary regulators though you certainly can

If the first stage is icing, either support local business and buy an Apeks sealed first stage, or talk to your LDS if they're good and see if you can buy the environmental seal from a legend and put it on the titan.
I doubt in that temp it's the first stage though, like the second stage that's causing problems. If that's the case, she needs to focus more on breathing and preferably go to a primary donate setup and switch regulators every few minutes if it's a regular problem.
 
https://www.shearwater.com/products/swift/

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