Drysuit Air dump valves issues

[FishDiver]

Proper weighting, so that you are not trying to squeeze the last four molecules of air out of the suit at the end of the dive, can help a lot, too.

I was guilty of this for my first few dozen drysuit dives. When I could use a wet suit for home water diving I loved to dive with just enough lead to barely control buoyancy for a five meter safety stop with empty tanks.

Drysuits have more variance in buoyancy between dives and I can't quite titrate the weight as finely. Adding a few pounds increases the margin for error in suit venting and enables you to stay a bit warmer.

 

[Peter_C]

I have used a few different brands of valves and never had water intrusion when pushing the valve in.

 

[Bubbletrubble]

I have used a few different brands of valves and never had water intrusion when pushing the valve in.

@Peter_C: Are you implying that water intrusion cannot occur upon manual activation of the exhaust valve? If you are, the design diagram of at least the Si-tech-branded valve would seem to point out the contrary. I have tested this out on my Si-tech valves, and water did get in if the valve was not positioned at the highest point.

 

[Bogie]

I actually have dozens of dives in my drysuits. Most buoyancy issues are in shallow water and at the end with 500 psi. I try to use minimum weight.

One technique while diving is if I am ascending and don't want to, I raise my elbow to release air. At depth this usually works fine. In shallower depths with waves rolling over just raising my elbow does not totally work because the ascent is faster than the air release. I now swim down a little then release (sometimes in vertical position as this releases air faster). If I depend only on air for buoyancy I can end up chasing the air ascent dog.

Undergarments can make a difference because some vent air better than others.

The suggestion of adding a bit more weight has worked well. While doing my safety stop I have noticed that the last quart of air is more difficult to release than if you have a few quarts of air but requires a bit more weight (2 lbs.). It seems those last air bubbles in your suit are more difficult to get out.

Anyhow, I love my dry suit and thanks for the suggestions.

 

[kathydee]

I've heard the hi-profile valves dump easier also. .

Yes the hi-profile Apex performed suprisingly well! Crank it down 1/4 turn and slightly roll the shoulder and... just the perfect dump ;-). At some levels I think I like it better than the sitec as the dump is a bit easier to control.

Hi Boogie,

I came across a great article written by Don explaining how to do controlled ascents that might be helpful ! I hope he doesn't mind that I posted the link.

Deep-Sea Sherpa Scuba 101 – Controlled ascents

 

[Anti-Hero]

If you can't vent fast enough in the shallows, try venting a little earlier, and possibly a little more often.

 

[Bubbletrubble]

One technique while diving is if I am ascending and don't want to, I raise my elbow to release air. At depth this usually works fine. In shallower depths with waves rolling over just raising my elbow does not totally work because the ascent is faster than the air release. I now swim down a little then release (sometimes in vertical position as this releases air faster). If I depend only on air for buoyancy I can end up chasing the air ascent dog.

@Bogie: I agree with Anti-Hero. I think you need to vent earlier and perhaps more frequently during ascent in the shallows. Swimming "down" won't help you dump air from an exhaust valve positioned on your upper left arm.

Getting vertical (upright) from horizontal trim will cause gas in your legs to move up into the torso and eventually leave through the exhaust valve if it's placed at the highest point. There's nothing wrong with that at all.

 

[kathydee]

Yes the hi-profile Apex performed suprisingly well! Crank it down 1/4 turn and slightly roll the shoulder and... just the perfect dump ;-). At some levels I think I like it better than the sitec as the dump is a bit easier to control.

Hi Boogie,

I came across a great article written by Don explaining how to do controlled ascents that might be helpful ! I hope he doesn't mind that I posted the link.

Deep-Sea Sherpa Scuba 101 – Controlled ascents

Hi Boogie,

In the above link I previously posted, Don explains how to vent early so you don't have a fast ascent.

In the following link Don explains useful body positions for ascents/decents.

Deep-Sea Sherpa Scuba 101 – Ascents and Descents

 

[Bogie]

Thanks for the article links Kathy. That is smart diving.

When I concentrate on my buoyancy my buoyancy control is quite good (not as good as yours but pretty good).

Unfortunately I sometimes have the attention span of Dug the dog in the movie "UP". When Dug sees a "Squirrel" he looses concentration and his head pops up and he totally thinks "SQUIRREL". Sometimes when I dive I think "Ling Cod, Leopard Shark, Sheep Crab, or even Lemon Nudibranch". That's why I love diving. I am always seeing something new.

I even got excited about a new worm (I guess it's a worm) about 3 inches long with a hard shell crawling along on a rock with legs at one end with little fish trying to eat it but couldn't because of the straw like hard shell. He got away. What drama.

 

[kathydee]

Thanks for the article links Kathy. That is smart diving.

When I concentrate on my buoyancy my buoyancy control is quite good (not as good as yours but pretty good).

Unfortunately I sometimes have the attention span of Dug the dog in the movie "UP". When Dug sees a "Squirrel" he looses concentration and his head pops up and he totally thinks "SQUIRREL". Sometimes when I dive I think "Ling Cod, Leopard Shark, Sheep Crab, or even Lemon Nudibranch". That's why I love diving. I am always seeing something new.

I even got excited about a new worm (I guess it's a worm) about 3 inches long with a hard shell crawling along on a rock with legs at one end with little fish trying to eat it but couldn't because of the straw like hard shell. He got away. What drama.

Boogie,

I totally relate! When I use to see something really cool like an octopus & call my buddy over, I would find myself ascending.
I just got excited, then my breath become shallower - couldn't help it ;-).

Lately I have been praticing zen octopi watching. Breath in, out... regular breaths no crazy hand motion, a few little back kicks. I think the octopi like me better now that I'm not scaring them. They seem to hang out much longer .

Your fish eating worm sounds interesting!