When to Use Dump Valve

[BRT]

I use the inflator for inflating and the dump valves for dumping.

 

[chris kippax]

For aqualung/sea quest BCD owners, this is what you are pulling on. Yes that looks like a paper clip just made out of stainless steel.

 

[Seaweed Doc]

On some BCs I've used, the dump valves vent air much faster than the oral inflator.

My Zeagle Ranger dumps "fast" from all points. My Oceanic travel BC seems to both fill and deflate slowly through the inflator hose.

How fast air leaves might be a secondary consideration (after body angle) in picking a valve to deflate.

 

[chillyinCanada]

I've a Scubapro Ladyhawk and use the butt dump almost exclusively. To me, it seems more natural than the inflator hose, though of course I use that if for some reason, I'm vertical instead of horizontal or bum up.

 

[1atm]

I know I had troubles getting my inflator hose high enough to release air on an ascent

inflator only when you are vertical, i.e. starting your descent, and finishing your ascent. bottom dump valve for everything else

You don’t need to be vertical to dump from the corrugated hose, its also possible in perfect trim. Try holding the corrugated hose up behind your head, this always works for me.

I also dive halcyon wings (Evolve with doubles, Eclipse with single tank). As to which dump to use, it kind of depends:

- Descend at beginning of dive: corrugated hose
- Fine tune buoyancy during the dive: kidney dump. This is much easer to control in fine amounts. Dont grab the string in a fist, but between two fingers right at the valve. A tiny stretch or twist with your fingers can release single small bubbles.
- Going up slopes e.g. in caves: corrugated hose (kidney dump makes no sense as you are parallel to the floor ie head up position)
- Autoinflate/wing inflate failure: kidney dump while kicking down and disconnecting the hose
- Ascend at end of dive: kidney dump in wet suit, because easier to control and handle; corrugated hose in drysuit, because this action also vents the dry suit, no point going back and forth between venting the suit and the wing, and to vent the suit your trim is likely 5-10 degrees off horizontal anyways
- etc

Do try the corrugated hose behind your head and let us know how it works.

Ah and needless to say: to effectively use the kidney dump, you obviously need to be in good trim, ie horizontal in the water column. If the wing is very empty already, you might need to roll a tiny bit to the right. The other thing to watch out for is to pull the kidney dump up in the direction of your tank - most new divers instinctively pull down on it, which doesn’t work well.

 

[TMHeimer]

Interesting read, in all my dives i have never used it. I thought it was only used in a emergency like an uncontrollable accent. I continue to learn from this group! Tanks Bill

My thoughts as well. I could use the dump if I thought of it (have practiced it), but the inflator/deflator is handy and both together, so the dump never crosses my mind.

 

[Neilwood]

Nearly always use the kidney dump.

Only ever use the insulator hose during vertical parts of the dive such as at the initial descent or the ascent at the end.

 

[Storker]

You might find you have to go a little bit arse up to use the butt dump.

Arse up and roll slightly to the right. Still might be a bit slow if there's hardly any gas left in your wing.

Whether I use my butt dump or the inflator dump valve depends totally on the situation. Sometimes using the butt dump works best, sometimes using the inflator dump valve works best. I'm definitely not religious about this (nor about much else...). Going slightly head-up might help dumping by moving your suit gas towards your shoulder dump valve if you're diving dry, though.

 

[caruso]

I second this. Anyone that has serviced pull dump inflators can vouch for their fragility. The worst I have seen is the aqualung version.

Never had an issue with my Seaquest. Dive gear is tough, it can take some abuse. I wouldn't be yanking the thing hard enough to rip it off the valve but I'd imagine it would be possible to do so.

 

[casts_by_fly]

Warm, tropical diver here. Scubapro lighthawk bcd. I never use the hose. Right shoulder dump to descend. Quick inflate at the bottom and dive. Most deflates during the dive are right butt dump valve as I think I am head down slightly (or my bcd bubbles to the butt naturally). Every now and then I gotta stretch out and might be head up and dump then. Sometimes I can’t find the air bubble in the wing and go head up a minute and dump. But for the most part I only use the right butt dump.

Rick