Procedure for a stuck bc infator valve.

[heliflyer]

This may have been asked in other threads,if so,sorry.After looking at another thread it made me woner what would be the proper procedure if ones bc inflator valve got stuck open at depth.What would be the first action to take,pull on a dump valve then disconnect hose or try and disconnect hose first?It would seem to me that you would want to start by pulling on a dump valve to compansate for the over inflating of the bc and to stop a "rocket"ascent to the service,would this be correct?Curious.Thanks.

 

[havnmonkey]

I believe that when Scubalab does BC tests they actually look for this type of failure. In a pool the tester will simultaneously depress the power inflater and the deflator. If the BC's deflator can dump air faster/as fast as the power inflator puts air into the BC then it gets a good score. Those that can't keep up with the power inflator receive a lower score in that area.

As far as procedure... I would try the deflator button first and then, if necessary, a dump valve. Many BC's have a dump valve integrated into the corrugated hose, because a dump valve on the bottom of the BC wouldn't vent if you were upright.
Abort the dive.

 

[CAPNVINNY]

I teach it by having the deflator button against the palm of my right hand while using my lefthand undo the hose at the same time

 

[Monkey Knife-fight]

I've actually had this happen a couple of times. Always at the beginning of the dive so it was never scary. Both times i ended up upside down finning down. I think the first time i started to dump from my rear dump valves but realized that wasn't going to fix anything until the BC stopped filling up. So i popped the LP hose off and then dumped and was OK. It all happened in a matter of seconds. Like i said it was early in the dive and not very deep so it could have been more complicated. Now i dive without the LP hose attached and manually inflate...at least until i get a new power inflator.

Chris

 

[ReefHound]

Disconnect the LP hose first. Treat the source problem before dealing with the symptoms. Your hand would already be holding the inflator anyway since they stick when you add air. Then dump with the inflator hose, practice this until it's basically one motion. If you're paying attention you aren't going to get that much extra air in your BC before you disconnect so you shouldn't be rocketing up.

Get in the habit of adding air in short bursts, and weight properly so you don't need much air in the BC anyway.

I wouldn't advise diving with the LP hose disconnected. Inflating manually is OK but the power button option should be there in case you need to add air quickly and you're already task loaded. And why take your reg out of your mouth if you don't need to?

 

[MikeFerrara]

One of my OW classes had the chance to see this failure first hand as well as the ambulance that came to get the diver who reacted incorrectly.

What amazed me is that they asked what one should do in that situation. My response was "You practiced it, don't you remember?" They didn't so I started teaching it a bit differently. As far as failures go, it's fairly common. For a while the Zeagle inflators were doing it all the time. For the most part they weren't real fast leaks but a couple of times they were. The scary part is that there were few times when a student acted correctly...yes it happened to students during trianing dives.

Anyway, dump from the inflator/deflator (hopefully you don't have one of those pull dumps or if you do that you aren't using it) and disconnect the LP inflator at the same time. From then on, should you need to inflate again for some reason do it orally. you need to be able to dive while inflating orally rather than just being able to do a fin pivot or inflate at the surface.

If you need to wear gloves, make certain that you can get that hose disconnected with gloves on. It needs to be fast and easy. If it isn't, find out why and fix it or the next ambulance may be for you.

 

[MikeFerrara]

Disconnect the LP hose first. Treat the source problem before dealing with the symptoms.

No. Hit the deflator and disconnect at the same time ideally. Often you realize that you're becomming buoyant first...so you dump. Then you realize that the thing is stuck so you disconnect. While you may be behind the 8 ball, dumping will give you some measure of control and disconnecting may take time anyway so don't wait to dump.

Your hand would already be holding the inflator anyway since they stick when you add air.

For a fact, not always true though it depends on the inflator design and the failure mode.

Then dump with the inflator hose, practice this until it's basically one motion. If you're paying attention you aren't going to get that much extra air in your BC before you disconnect so you shouldn't be rocketing up.

Divers who have this happen definately do rocket up

Get in the habit of adding air in short bursts, and weight properly so you don't need much air in the BC anyway.

Adding air in short bursts is probably a good idea but how much air you need will vary depending on how much gas and gear you are carrying.

I wouldn't advise diving with the LP hose disconnected. Inflating manually is OK but the power button option should be there in case you need to add air quickly and you're already task loaded. And why take your reg out of your mouth if you don't need to?

I agree but any diver should be able to dive without a power inflator. As I said, this is a failure we've seen a number of times. Taking the reg out of your mouth momentarilly shouldn't be a big deal.

 

[texdiveguy]

First things first--- Disconnect the lp hose!

 

[ShakaZulu]

Why not take care of your gear and avoid this from happening. Unscrew the BC inflator hose from the BC and rinse it properly after every dive. Check it before the dive.

Had this happen to me after I got roled in the surf on the first dive. Didn't inflate the BC with the inflator on the second dive (used my mouth). During my desend, I pushed the button to add air to the BC (20ft), and before I knew it, I was on the surface. Didn't even have time to remove the LP hose. Goodluck.....

 

[ReefHound]

No. Hit the deflator and disconnect at the same time ideally.

wait to dump. For a fact, not always true though it depends on the inflator design and the failure mode. Divers who have this happen definately do rocket up

I agree but any diver should be able to dive without a power inflator. As I said, this is a failure we've seen a number of times. Taking the reg out of your mouth momentarilly shouldn't be a big deal.

Thanks for dissecting my post line by line. If it's one or the other, I'll disconnect my LP hose first though. You have two problems - air going into BC and air in BC making you positive. Disconnecting LP hose solves first problem completely, freeing you to work the second problem. Venting BC solves the second problem completely, situation resolved. If you vent first and find you can't vent faster than air is going in, you've wasted time and are now in a real jam.

But... if you'll notice I also said "practice this until it's basically one motion" so I essentially agree that you do both at the same time.

I'm a diver who had this happen and I definitely did not rocket up.

The only part you said that doesn't make much sense to me is that often excessive buoyancy is what one notices first. I find that power inflator rather noisy, I can not only hear mine well with a hood but also my buddy's. If I press the button and hear the hiss, let go of button and continue hearing the hiss, I'll know in about 1 second that there is a problem. Maybe because I've had this problem I'm more observant than most but I typically hold the inflator a few seconds after I release the button to ensure it isn't sticking.

But it's not like I'm constantly hitting the inflator button throughout a dive, typically a few times on descent and to level out at bottom depth.

Now maybe that is where we are differing. If someone cannot hear the sound or is oblivious to it, and the first sign they get is when they wonder why everybody else is sinking so fast, then maybe they better vent immediately.

My advice to not dive with disconnected LP hose was not to say that one should be dependent on it. Of course you need to know how to be comfortable with manual inflation. The point was that the power inflator should be there as an option and not to begin a dive with faulty equipment.