Aqualung Titan XL Venturi Adjustment Lever question

[Scubasteve1982]

Hello,


Kind of a newbie question here.

I've recently purchased my first regulator. Titan XL. I've made 50+ dives in the last 2 years and always rented. So here's my question.

The Venturi Adjustment Lever- What's it's purpose? I've read it's to adjust airflow, is that correct? What should I be looking for? Is it a personal preference thing? When would I use it?

 

[mike_s]

it's bascially to adjust the airflow.

I think you'll find that once you get used to it and quit fidgeting with it, that you'll never move it again (unless it free flows on the surface). I leave mine "wide open" 99.9% of the time. (and never touch it).

If I had to buy again, I doubt I'd say it was worth the extra $$$

 

[Scubasteve1982]

it's bascially to adjust the airflow.

I think you'll find that once you get used to it and quit fidgeting with it, that you'll never move it again (unless it free flows on the surface). I leave mine "wide open" 99.9% of the time. (and never touch it).

If I had to buy again, I doubt I'd say it was worth the extra $$$

Thanks for the info!

 

[Kern]

When you have the venture set to off/-, a guard slides around the valve spindle changing the direction of the air flow inside the 2nd stage. It now blows back towards the diaphragm, in this position the pressure in front of the diaphragm increases, thus helping to keep it closed. You can still use it like this with no problems. It will require a little more sucking to open (this has nothing to do with the cracking pressure) & when you stop sucking it will automatically be blown shut.

When you turn the venture to the on/+ position, the guard is rotated out of the airflow so that it now blows straight out the mouth piece. This reduces the pressure in front of the diaphragm, it now takes next to no effort to suck open the diaphragm & it will continue to supply air without the effort of any further suction. The airflow will continue until you breath in, thus increasing the pressure on the diaphragm & closing down the air flow.

Set the venture to off/- while on the surface to prevent free flows. Set it to on/+ when you put it in you mouth prior to decent to relieve the WOB.

 

[herman]

When you have the venture set to on/+, a guard slides around the valve spindle changing the direction of the air flow inside the 2nd stage. It now blows back towards the diaphragm, in this position the pressure in front of the diaphragm increases, thus helping to keep it closed. You can still use it like this with no problems. It will require a little more sucking to open (this has nothing to do with the cracking pressure) & when you stop sucking it will automatically be blown shut.

When you turn the venture to the off/- position, the guard is rotated out of the airflow so that it now blows straight out the mouth piece. This reduces the pressure in front of the diaphragm, it now takes next to no effort to suck open the diaphragm & it will continue to supply air without the effort of any further suction. The airflow will continue until you breath in, thus increasing the pressure on the diaphragm & closing down the air flow.

Set the venture to on/+ while on the surface to prevent free flows. Set it to off/- when you put it in you mouth prior to decent to relieve the WOB.

Unless the AL is different than any others I have seen, the explanation is great but you have the on/+ and off/- backwards. + increases the venturi effect (more likely to freeflow but assist in breathing). I use mine, it is set at (-) at the surface and all the way (+) when in use.

In any case, if the reg is working properly, if you move the lever to the most assist (it will be easy to figure out which is which ) and push the purge button it should violently freeflow and continue to do so until you stop it by covering the mouthpiece with your hand. In the opposite position it should not continue to freeflow as soon as you release the purge button.
Whether to use it or not is a personal choice. With it set to max assist and you breathe fairly deeply it will tend to slightly force feed you air, how much depends on the reg. Some divers don't like the feeling. I don't mind as long as it is not too noticeable, but you can always back off on the setting until you find what works for you. On the surface a reg that can easily be started freeflowing is a pain in the rear, this is esp. true if it's an octo so as a habit I set mine back to min assist unless I am submerged.

 

[Kern]

Unless the AL is different than any others I have seen, the explanation is great but you have the on/+ and off/- backwards.

Quite right, must be getting dyslexic in my dotage. Mmm, can't spell venturi either, must be having one of those days.

 

[mike_s]

When you have the venture set to on/+, a guard slides around the valve spindle changing the direction of the air flow inside the 2nd stage. It now blows back towards the diaphragm, in this position the pressure in front of the diaphragm increases, thus helping to keep it closed. You can still use it like this with no problems. It will require a little more sucking to open (this has nothing to do with the cracking pressure) & when you stop sucking it will automatically be blown shut.

When you turn the venture to the off/- position, the guard is rotated out of the airflow so that it now blows straight out the mouth piece. This reduces the pressure in front of the diaphragm, it now takes next to no effort to suck open the diaphragm & it will continue to supply air without the effort of any further suction. The airflow will continue until you breath in, thus increasing the pressure on the diaphragm & closing down the air flow.

Set the venture to on/+ while on the surface to prevent free flows. Set it to off/- when you put it in you mouth prior to decent to relieve the WOB.

I think he's asking about the Adjustment knob, not the venturi.

The Venturi is the lever that is inside the Adjustment knob.

here's a diagram of the AL Legend LX, which is almost the exact same as the Titan LX 2nd stage. You can see the Adjustment knob (#33 & #34) and the Venturi (#21)

 

[Kern]

I think he's asking about the Adjustment knob, not the venturi.

Why, the OP asked about "the venturi adjustment lever", not the cracking pressure control?

Hello,


Kind of a newbie question here.

I've recently purchased my first regulator. Titan XL. I've made 50+ dives in the last 2 years and always rented. So here's my question.

The Venturi Adjustment Lever- What's it's purpose? I've read it's to adjust airflow, is that correct? What should I be looking for? Is it a personal preference thing? When would I use it?

 

[mike_s]

Why, the OP asked about "the venturi adjustment lever", not the cracking pressure control?

damn.... you're right

I just read the Adjustment lever somehow in my mind I guess....... thanks for correcting me. (I'll go take my foot out of my mouth/keyboard now. )

 

[redacted]

damn.... you're right

I just read the Adjustment lever somehow in my mind I guess....... thanks for correcting me. (I'll go take my foot out of my mouth/keyboard now. )

Mike

Thanks for the schematic. What is the difference between the LX and the LX Supreme? Is it simply a cosmetic difference in the case?