Recent double hose reg training?

[rx7diver]

I have an octo on mine because I'm under no false assumptions that any of my dive buddies would be able to buddy breathe a double hose.

A few months ago I was playing around, thinking of possible DH configurations for very cold water diving. So, I thought to try a Y-valve fitted with my DH (with drysuit whip) on one post and a single-hose reg (with SPG, BC inflator hose, and backup second stage) on the other. My intention was to use one of my Poseidon's. Alas, the Poseidon wouldn't quite work, so I used one of my Scubapro Mk 10 + G250/Balanced Adjustables, instead.

I never dove this configuration. However, this was a fun exercise.

rx7diver

 

[JohnnyC]

A few months ago I was playing around, thinking of possible DH configurations for very cold water diving. So, I thought to try a Y-valve fitted with my DH (with drysuit whip) on one post and a single-hose reg (with SPG, BC inflator hose, and backup second stage) on the other. My intention was to use one of my Poseidon's. Alas, the Poseidon wouldn't quite work, so I used one of my Scubapro Mk 10 + G250/Balanced Adjustables, instead.

I never dove this configuration. However, this was a fun exercise.

rx7diver

That's pretty slick! I've never used a double let hose in cold water. How prone are they to freezing?

 

[northernone]

That's pretty slick! I've never used a double let hose in cold water. How prone are they to freezing?

Some of us swear by them as a superior design for cold water.

On my small data sample I've froze single hose regs but not a double hose yet.

 

[rx7diver]

How prone are they to freezing?

JohnnyC,

My understanding is, my U.S. Divers DA Aqua-Master double hose reg is much less likely to freeze up than a lot of single-hose regulators--because it's internals do not come into direct contact with the water. (It is a diaphragm reg, after all.)

In fact, by placing my Mk 10 in the mix in the configuration above, I have probably increased the chances of freeze up (since a Mk 10 that is not "environmentalized" is not a particularly good reg to use in extremely cold water). My Poseidon Odin would have been a much better choice, probably. However, the Odin is a bit too fat, and hoses coming off of it don't route particularly well for this configuration.

One of these days I'll give this a dive. (Drysuit has shrunk, though.)

rx7diver

 

[Couv]

Both stages of a double hose regulator are sealed from the environment. See the post linked below for great pictures of a DH in ice diving action.

Project Argonaut, totally new, vintage style DH regulator

 

[rhwestfall]

I've used my DH regs exclusively for ice dives. They have many advantages, starting with being a large heat sink, sealed (diaphragm), and the second stage mechanism is not seeing your moist exhalation vapors to possibly ice up.

@rx7diver : you have the Phoenix stage, why then the double valve? With the Phoenix, you have all the ports needed.

 

[Couv]

...the second stage mechanism is not seeing your moist exhalation vapors to possibly ice up.

Good point, I never even considered. One way, non-returning loop. Both stages see dry tank gas only.

 

[Sam Miller III]

@rx7diver

"I just came across one of them when I was searching for my copy of "The New Science...". This textbook, by Robert R. Springer, is titled "Skin & Scuba Diver's Digest -- Fundamentals, Techniques, Equipment for Novice and Expert," and has copyright date MCMLXXV [1975]. Interestingly, this book contains relatively little treatment of double hose regulators--though it has several pictures and illustrations of divers diving them."
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Bob Springer was local to Orange County California

Dive history is just too boring

 

[rx7diver]

@rx7diver : you have the Phoenix stage, why then the double valve? With the Phoenix, you have all the ports needed.

@rhwestfall,

Additional insurance against freeze-up in very cold water. There is an increased chance of 1st-stage freeze-up if too much is being demanded of a 1st stage. So, drysuit for one first stage, and BC for the other 1st stage. And if you and a buddy are sharing gas, then one 1st stage for you, and the other first stage for your buddy. Etc.

When I dove single-tank recreational dives in the Great Lakes, for example, I would wear a large cylinder with a Y- or H-valve, with a complete Poseidon Odin mounted on each outlet. (I actually prefer a Y-valve to an H-valve.)

ETA: Also, if you do get a free-flow from a freeze-up and you shut down the offending post, you still have gas to breathe and one source of flotation.

rx7diver

 

[rhwestfall]

@rx7diver : I just run an independent (pony), also with a spare QD for DS.