Drysuit shoulder dumps: Apeks vs Si-Tech

[Alekseolsen]

Now I only have experience with Apeks dump valves, but I did hate - intensily- the apeks "high profile" valve as it dumped super slow. Low profile one I've been happy with, also never been wet from it, in ~250 dives.

If Sitech is fastr that would certainly be interesting

 

[runsongas]

the sitech low profile is slightly better, but the apeks low profile isn't that bad. it helps if you have an undergarment that has a vent patch on the arm that matches up with the dump (or just tape down that area) and don't run it all the way open and it works fine.

 

[NW Dive Dawg]

Hey Wib.... I dive a Tri Lam with SiTech valves (about three years old) and although the dump valve is not as low profile as I might like it to be, the valve works well and the higher profile may even be bit easier to operate with heavy gloves. (recent pic below). I do think there might be a bit of interference with my undergarment because like you, I still need make a very deliberate shoulder up move to get it to really dump....and that's with it fully wide open.... Otherwise no issues, no leaks and I'm good with it..

And slightly off topic.....I really don't much like the newer SiTech inflator valve. The best I can describe it is that it has a "side-slide" operation rather than just a simple center button push....if that makes sense. I've gotten used it and it works fine...but if I had my druthers I'd rather have the center "push" as it's a bit easier to operate with either hand and just one less thing to think about..

All in all I'd say that SiTech valves are very robust both in function and durability...

 

[Celt]

I was getting a little wet with an Apeks low profile. I thought a bit a dirt so I stripped it and found a crack running half way around it. Cheap sh*t.

 

[Degenerate]

Love my Apeks high profile, dumps like an absolute dream.

 

[Wibble]

it’s a new premium brand membrane drysuit and has the Apeks low profile dump fitted.

Also, I have a new BZ400 (made to measure) undersuit. This fits well and is not baggy.

Have been diving with these for the 14 dives thus far this season down to 65m/215ft. It’s never been easy to get the drysuit to dump and it was particularly difficult on the last dive. I triple checked that the dump was fully open but it was a real pig to get it to burp.

Obviously this isn’t a particular problem in the bottom phase, nor on dives coming up a shot line. But it really isn’t pleasant on a free ascent under an SMB.

There’s obviously several changes which could be working against effective dumping here. I need to isolate the various elements.

Probably the easiest is to go for a lake dive with my old underclothes (FE Arctic Expedition) which do work.

Can easily switch from the Apeks low profile dump to the Si-Tech high profile dump (checked, fits the Apeks hole/pad, just need to check for leaks!). Never had problems with the Si-Tech dump in many hundreds of dives in the old drysuit.

The lake at just 10m/33ft that allows solo diving should be deep enough to verify these things. Back to sidemount again.

If it is the BZ400, then need to see if there’s some modifications which might help to get it to dump more effectively such as sewing on a patch of porous material around the dump. Or attack it with the tip of a soldering iron?


In summary: seems the the Apeks dumps work OK for most people. If that’s the case then need to look for other causes with the undersuit being the obvious first step.

 

[RedSeaDiver2]

If it was me I would change the valve to a SiTech as the first step before attacking the BZ400 with a soldering iron.

 

[Snusmumrik]

I was getting a little wet with an Apeks low profile. I thought a bit a dirt so I stripped it and found a crack running half way around it. Cheap sh*t.

Typical overtighten valve issue.
IMHO. I hate Si Tech valves. I knew hatred when i try to overhaul Si Tech dump valves on my buddy's rebreather.
Such a poorly designed piece of s..t. It cannot be totally disassembled. And imagine - there's a plastic spring washer.
Dump valve also cannot be totally disassembled to replace rotational o-ring.
Apeks valves - both, dump and inflate - are made much better, also with disassembly issues, but you can service it on your own.

 

[admikar]

I had/have 2 Apeks low profile dumps. Both of them work fine and never let any water in.
I dive it with 2-3 clicks from wide open.

 

[DiveTucson]

Hey Wib.... I dive a Tri Lam with SiTech valves (about three years old) and although the dump valve is not as low profile as I might like it to be, the valve works well and the higher profile may even be bit easier to operate with heavy gloves. (recent pic below). I do think there might be a bit of interference with my undergarment because like you, I still need make a very deliberate shoulder up move to get it to really dump....and that's with it fully wide open.... Otherwise no issues, no leaks and I'm good with it..

And slightly off topic.....I really don't much like the newer SiTech inflator valve. The best I can describe it is that it has a "side-slide" operation rather than just a simple center button push....if that makes sense. I've gotten used it and it works fine...but if I had my druthers I'd rather have the center "push" as it's a bit easier to operate with either hand and just one less thing to think about..

All in all I'd say that SiTech valves are very robust both in function and durability...

SI TECH makes about 4 maybe more different style inflation valves and they are all interchangeable. You could always switch to a high or low profile center push button if you don’t like the slide inflation valve.