How does the Poseidon Xstream first stage work?

[js47]

My question is, how does the Poseidon Xstream first stage work? What makes it different from other first stages? And what exactly is their “Thermo-Dynamic Antifreeze” (TDA) system, and how does it work? The technical info page on Poseidon’s website talks about ”through-flowing water” but I was under the impression the first stage was environmentally sealed....

Hopefully someone who has serviced an Xstream can offer some info?

Thanks in advance,
Jake

 

[tbone1004]

the first stage is not sealed. It is the only regulator that is unsealed that can pass all of the cold water testing. It does this because water is able to flow all around the spring chamber which is their TDA system. Ice just doesn't build up inside of it and lock the regulator open. It also makes cleaning it a lot easier than any other first stage because water can easily flow all around it.

How does it work? It is a demand valve, so it works basically like all of them. The difference is they use a ruby sphere in lieu of a traditional HP seat which minimizes the risk of IP creep due to something getting in there, wore out, etc. and also minimizes the required number of sealing surfaces.

 

[rhwestfall]

https://siteassets.pagecloud.com/di...3-ID-49dcfa56-9560-40f3-cc0d-33fc30364d20.pdf

 

[rhwestfall]

just a side note: you will notice SP has opened up the ambient ports on the MK-25 Evo. Likely an attempt to achieve similar results....

 

[tbone1004]

@rhwestfall note the word attempt lol. It helps, but not nearly as effective

 

[kelemvor]

So they use a piece of actual ruby instead of whatever material (rubber?) a seat is normally made from? That sounds pretty nifty. Any chance in an acutal photo of a normal seat vs a poseidon xstream?

 

[rhwestfall]

@rhwestfall note the word attempt lol. It helps, but not nearly as effective

I chose those words with purpose......

 

[rhwestfall]

the Ruby replaced a SS ball previously implemented, and likely changed due to thermal properties.......

@kelemvor :

"Typical" HP seat:

Poseidon:

 

[shurite7]

just a side note: you will notice SP has opened up the ambient ports on the MK-25 Evo. Likely an attempt to achieve similar results....

To my knowledge the Mk25 has always had the ambient holes. A friend of mine dives the X-Stream while I dive the Mk25. We both dive in cold water mountain lakes and sometimes below the ice. My Mk25 has always performed well. So has his X-Stream. Personally I like both regs. The "typical" HP seat in the pic above is not used in the Mk25. It was used in the Mk5/10. The Mk10+ went to the newer HP seat which the Mk20 and 25 use. What I don't know is what it is like to service the X-Stream in comparison to the Mk25.

What is interesting is another friend of mine, who services every brand, got a group together and went up to a lake around 4000' in elevation with ice still floating and tried out all sorts of regs. What was determined, is if you don't know what you are doing or if you really know what you are doing you can get a reg to free flow in cold water conditions. The hardest reg to get to free flow was the Delta IV which my friend didn't like servicing. He prefers Apex over SP and Po.

 

[lexvil]

I may be mistaken but isn’t the Poseidon ball the valve and not the seat?