H-Valves & config for single tank or doubles

[Blackwood]

I wrote up a response about doubles valve failures, but decided this (hose routing H valves) isn't the proper venue.

 

[Lobzilla]

What is your take on using one SPG and one pressure transmitter for air integrated computer?

 

[h90]

(This is split from another thread to avoid a hijack.)

I use an H-valve on my single tanks just so that I can swap between doubles and a single without changing the hose configuration on my regulators. Post your compatible H-valve / doubles configs here for your brand of regulator. I'm starting off with Scuba Pro MK17s and MK25s. BTW, if you have found a better config for MK25 or 17 regs please share! Interesting to note that even though MK25's have a swivel base they don't dress as neatly as MK17's :shocked2:

Question: on this setup are you able to shut down the valves under water?
(I just sit in front of the computer, imagine where the second valve is in case I mounted the tank a bit too low, imagine I dive and have gloves and try if I can find and close it quick (hope no one sees me closing invisible valves)).
Can you reach it??? On the dry safe place everything looks easy. But under water in a surprise situation?

 

[lowviz]

I dive with two SPG's also and would rather accept the slight risk of a SPG failure (which would happen in a non emergency situation) than diving a tank blind (as to its volume) in an emergency situation.
I have heard it said that knowing the contents in a tank doesn't really matter as you are going up anyways and you "have what you have" but I would rather base my ascent profile by knowing the volume I have.
I would like to know if I could do any deco I might have, have to alter the stops I am making or if I have to blow all my stops in order to make the surface.

I also respect the fact that others assess their risks differently.

Couldn't have said it better, myself.

I wrote up a response about doubles valve failures, but decided this (hose routing H valves) isn't the proper venue.

Go for it, this is a pretty loose thread. (But mostly, I always appreciate hearing the reasons behind differing opinions)

What is your take on using one SPG and one pressure transmitter for air integrated computer?

You have the added advantage of your computer tracking your gas consumption (if the failure is on the SPG's post.) That would be a valuable SAC rate for gas planning purposes.

Question: on this setup are you able to shut down the valves under water?
(I just sit in front of the computer, imagine where the second valve is in case I mounted the tank a bit too low, imagine I dive and have gloves and try if I can find and close it quick (hope no one sees me closing invisible valves)).
Can you reach it??? On the dry safe place everything looks easy. But under water in a surprise situation?

There are several ways to do this and a SB has few good threads on this subject, for a single tank I just push the base sideways to get the tank to about a 30 degree angle. H-valves aren't symmetrical on the tank, pushing the tank in one direction will be an easier reach than if you push it the other way. Easiest to just try this, harder to explain.

-Thanks, all.
lowviz

 

[Michael Kazma]

I would never use a wireless transmitter. There are many issues with them and the way they convey your gas consumption, an SPG and your brain is much better.

About planning your assent and deco without knowing your gas left.... If you are diving doubles and have deco then you should have your deco gas in your stage tank(s), so all you have to do is make it to your 1st stop.

 

[jtivat]

For me it is just a wasted piece of gear I don't need. 99.9% of the time a reg failure will be the one I have in my mouth. This is my 7' hose coming off my right post. My SPG is on my left post so if I have a problem I switch regs and still have an SPG not that I feel it is really needed. I know what my SPG says within 200 psi at any point in my dive without looking. A free flow is going to be shut down within seconds so if I am diving thirds I know I have plenty of gas to do a normal assent. For me it is just cleaner and when you have lots of deco gas and switches cleaner is just better IMO. I don't think two SPG's will hurt you but I personally do not see the need.

 

[rjack321]

No, the wing inflator does an 'S' bend over the wing for the 25's, again the 17's are easy.

Why? The wing inflator is on the left shoulder for most if not all wings. This hose should not be crossing behind the neck.

Agree on ditching the 2nd SPG in what is already an overcomplicated single tank setup anyway.

 

[lowviz]

Why? The wing inflator is on the left shoulder for most if not all wings. This hose should not be crossing behind the neck.

The wing inflator has to exit at an odd angle for the MK25, exits very nicely for the MK17. I always have my suit and primary reg on the same post and my wing and backup reg on the other.

........Agree on ditching the 2nd SPG in what is already an overcomplicated single tank setup anyway.

I would agree with you for a single tank situation, if it wasn't for the fact that my only reason for having an H-valve on a single tank is just to keep from reconfiguring my regs. The MK17's work very well on either single or doubles. Curious to see if other regs do the same, thus this thread.