LP vs HP question

[dannobee]

No need to bash HP tanks like PapaBear rips Split Fins...

Don't get me wrong, my most commonly used single tanks are HP100's, but when I'm on one of the commercial dive boats, I'll bring one of my LP95's. I've had the <2400 psi fills with my HP100's, that's why I bring this up. Having only 60 cu ft of gas when you expected a lot more is no fun.

 

[DA Aquamaster]

That makes sense - if you already own a LP95.

If you don't already own one and are in the market for a new tank, it makes sense to get a special permit E or X series 3442 psi tank as with a tank the same same size and weight of a LP95 you will get a tank that will hold a similiar gas volume at similar fill pressures as the LP 95, but with the added advantage of legally holding a whole lot more at the rated pressure of 3442 psi. when that is available without having to hope you can get it overfilled.

No one is saying LP95's should be consigned to the scrap heap, rather it is a case of now being able to buy essentially the same tank in terms of size and weight in a 3442 psi special permit format that allows a legal overfill to 3442 psi.

 

[Stu S.]

I sold my LP-95. It was like having a barrel of beer on my back. The "overfill" air was probably comsumed hauling the thing around. Even though I was getting fills in the 110-120 cu. ft. range, my bottom times are the same using a correctly-filled HP-100.

 

[rds912]

how about the faber FX117? seems like it would be a good tank I should get about 95cf at 2800psi?

 

[limeyx]

They all have the Pro valve. It seems that the only difference is that the LP95+ is only rated to 2640. Why go with the limited LP95 when the HP119 is very similar and can hold more cf at higher pressure? I don't know why the LP would be considered unless it was cheaper. I advise trying out a lighter tank before purchasing something heavier that may not meet your future needs. The HP100 is my favorite tank and the HP120 is lighter but it may be too long.

because LP is easier to Partial Pressure fill.

 

[Stu S.]

3000 psi. in an LP-85 is 96.6 cu. ft of gas. It is a light and easy tank to dive with. That's the one I didn't sell.

Stu.

 

[cmburch]

because LP is easier to Partial Pressure fill.

What does this mean? Wouldn't the pressure be the same when each tank filled to the same pressure? For a LP95 and HP119? Just more CF for the HP119.

 

[cmburch]

how about the faber FX117? seems like it would be a good tank I should get about 95cf at 2800psi?

Maybe start a new thread with the tank names/types to find someone that has used the ones you desire. Or search for the name. I have only experience with Al80, HP100, HP130, LP85.

 

[dannobee]

What does this mean? Wouldn't the pressure be the same when each tank filled to the same pressure? For a LP95 and HP119? Just more CF for the HP119.

Partial Pressure Blending is a way to mix nitrox into your tank. What he's saying is that when your source tank of oxygen gets low, it's easier to get the right mixture when the tank's rated pressure is low.

 

[limeyx]

Partial Pressure Blending is a way to mix nitrox into your tank. What he's saying is that when your source tank of oxygen gets low, it's easier to get the right mixture when the tank's rated pressure is low.

Yah, exactly. Everyone knows LP is way easier to fill with partial pressure than HP.
besides, I can get a "full" fill in my LP -- if I get an HP, since the boats only fill to 3000 psi hot, I will never have a full fill.