Question re: Use of Dump Valves

I have a Cressi-Aqua Light-R BC and it's superb for traveling and tropical diving.

I try to do my diving with none or minimal use of my inflator/deflator valve. I also try to descend pulling my right chest valve as I find it easier than using the inflator/deflator valve.


I make frequent releases from my right chest valve when planning to ascend. I also release air from my rear lower right valve but I find I have to turn upside down to get most of the air out. The turning upside down isn't a problem and is actually fun but is it "normal" to get a lot of air buildup in that area and is turning upside down the best way to release it?

I have seen some new BC's with 2 valves on the top of each shoulder of the B/C in addition to the normal inflation/deflation hose. That seems like a better idea.


Any comments or suggestions will be appreciated.

Thanks,


Sy

As far as I've ever known, the only time you would get a "build-up" of air in the bottom of your BC would be when you were upside down; but go rightside up and that "build-up" will then be in the top of the bladder. Unless you have some sort of constriction on the bladder that is only affecting your dumping, but I can't think of what that would possibly be. If you're dumping from the lower valve while rightside up; then yes, you will not be able to get all the air out, which should not be a surprise - air goes to the highest (least deep?) part of the BC bladder due to that mysterious floating quality that it has underwater. If you are heads-up, you use your shoulder dumps; if you are fins-up, you use the lower valves; if you are perfectly horizontal, then you have a choice, I suppose.

I don't exactly understand the setup of the new BCs you describe; which ones are you referring to?

Are you sure that you have to go head down to dump from the lower right rear dump? Most butt dumps work well if you are truly horizontal or just a tiny bit head down.

It might be what you consider normal attitude is a bit head up. The best way to check that out is to hover a foot or two above a horizontal bottom, then see what touches first as you descend onto the bottom. Also ask your buddy to take a look at your trim.