Manual Injection Valves

[v101]

Hello RB Divers;

I am a newbie still at rebreather diving, getting more hours every time I dive my unit. I had a question about pros/cons to using a Manual injection valve, here is an example, but there are many others to choose from:
Golem Gear Manual Injection Valve for Diluent

i wanted to as others who dive them, how they like them, and if they only use a manual add valve for diluant/oxygen or both.

 

[tstormdiver]

Not sure which unit you are diving,.. the type of counterlung you use can make some difference. I have a Prism2 & just recently changed from the front mounted counterlungs that came with the unit, & has the gas addition points built into the counterlung, to back mounted counterlungs, where I now have manual gas addition valves. It will probably take me a few dives to get used to the new addition points. I have tried a unit in the current configuration before I pulled the trigger & it took me a minute or so to find the addition blocks, but was no big deal.

 

[v101]

I should have posted the unit, argg.
I am diving a KISS SIDEWINDER.
So for me when I goto SC mode, I have to really inhale to get the gas into the counter lungs. the manual add block would help for this aspect.

 

[tbone1004]

most all cave divers I know use MAV's only and only use the ADV if on the trigger or on initial descent. Which one ends up being personal preference

 

[JohnnyC]

ADV only for ascent, MAV for everything else after. MAV's on both diluent and O2. If you've gotta do a dil flush, you don't necessarily want to be breathing the loop contents. Without a MAV, you've gotta vent then pull against the ADV (depending on the unit). In some situations that may be dangerous. With a MAV, you just loose lips the BOV and blast it. If you need to dewater the unit you need one.

An exception is something like the Meg plunger-style ADV. You can mash it down and it will act like a MAV.

 

[wedivebc]

ADV only for ascent, MAV for everything else after. MAV's on both diluent and O2. If you've gotta do a dil flush, you don't necessarily want to be breathing the loop contents. Without a MAV, you've gotta vent then pull against the ADV (depending on the unit). In some situations that may be dangerous. With a MAV, you just loose lips the BOV and blast it. If you need to dewater the unit you need one.

An exception is something like the Meg plunger-style ADV. You can mash it down and it will act like a MAV.

If you are injecting dil on ascent you're doing it wrong.

 

[JohnnyC]

Hah! Yes. Typo for sure. ADV on DESCENT. Unfortunately i’m unable to edit the post.

 

[DA Aquamaster]

I should have posted the unit, argg.
I am diving a KISS SIDEWINDER.
So for me when I goto SC mode, I have to really inhale to get the gas into the counter lungs. the manual add block would help for this aspect.

I'm not sure how the ADV is adjusted on the Sidewinder, but on the Sidekick it is pretty easy to just move the ADV paddle a little farther down the stem until you reach the sweet spot where it will fire without having to inhale too hard, and yet not be super sensitive.

One advantage of the Sidewinder is that the ADV can be manually operated by just moving your elbow back so the back of the arm hits the ADV - assuming you've to it set up properly.l

There's nothing wrong with a dil MAV, but there's also value =n keeping things simple, so I'd advise looking into the other options before adding the extra holes, valves, hoses and general complexity of a dil MAV on KISS.

 

[doctormike]

The CE version of the JJ comes with a dil MAV, the international version (which I have) does not. I was thinking about adding one, but I really couldn't figure out why I would want one.

Maybe this is something that varies unit to unit, but my ADV is easily reachable on my left T-piece. Pushing it does the same thing that a MAV would do, right? Do some ADVs not have a button?

I guess a dil MAV gives you another place to plug in offboard gas, although I can do that now with my O2 MAV. Maybe solenoid failure and running out of dil at the same time? I must be missing something....

 

[kensuf]

I've had an ADV stick open necessitating shutting it off by a gas shut-off. Adding DIL came down to either opening the ADV back on/off or using a DIL mav.