Single first stage on twinset?

[wedivebc]

The man did lots of great stuff...but

Well he was a chain smoker, thought diving on o2 would be cool until he passed out at 45', and did plenty of other stuff that would get him totally hammered on these forums if he did them today. Including diving a single 1st on a set of doubles.

Yeah, Jacques didn't have all you internet experts to tell him how to Do It Right

 

[Bob DBF]

That was a single reg manifold. Different beast.

Actually, I have an old school non-isolation manifold that can mount two regs. A center mount for a double hose and a mount over a tank for a backup single hose.

As long as the OP understands that he is effectively diving a single tank, I don’t see the problem. Of course if one doesn’t believe in diving a single tank, with a single reg, that is a another discussion.


Bob

 

[Ghost95]

Find a nasty used junk reg. Put plugs in all the ports. Put it on the unused valve. The local shop you get fills at probably has something in the junk pile they will give/sell cheap.

I may be wrong but my understanding is that it is a bad idea to have a completely plugged first stage, that could become pressurized, attached to a tank. The way I understand it is that with a completely plugged first stage, if you have a roll on of the valve, and the IP runs away, a possibility with a junk regulator, you could over pressure the LP side of the reg.

If the IP runs away you could blow off the LP caps/turret/side of the reg and cause damage or injury to things and people near by. Including the back of your head.

Isn't that why they say never work on a reg without a second stage attached, so a runaway IP will just force the second into free flow or pop a hose before the first stage deconstructs itself?

My understanding anyway.

 

[broncobowsher]

And you do a valve drill to turn that post back off where it should be, what was that problem again?

 

[Ghost95]

How would you know the valve got turned on if there are no hoses or anything coming from it? Other than the junk first stage deconstructing it's self that is.

I don't tech so I don't know but, do the techies constantly check their valves throughout the dive to make sure they didn't get rolled on or off?

 

[divad]

You can just remove a port plug and it'll vent

You mean the HP port plug right?

 

[martincohn]

Yeah, Jacques didn't have all you internet experts to tell him how to Do It Right

QUICK someone grab that comment that buzzed right over someone's head.

 

[The Chairman]

It's OK to dive with a single 1st stage on a twinset.
I wouldn't try to plug the second valve. Nothing is served in doing so and you can jam the plug if you accidentally charge that side.
Both sides will drain from one side if the isolation valve is open.

 

[broncobowsher]

You mean the HP port plug right?

If you like. I would pull a LP port plug.

And all this is to do is keep water, salt, silt out of the valve. You can clear 99% of that with a blast of air at the end of the dive. But if you have a plug sealing the valve the you don't have to worry about that 1%. Or salt crystalizing as the water dries out. Or much of anything else.

Worried about a roll on with a regulator with all the ports plugged? what about a roll on with nothing at all? A junk regulator at least gives some protection from ingress and roll ons.

Is it needed? No. Completely viable to just dive with the port open to the water. But there are better ways of doing it and protecting the valve and maybe the inside of your tank(s).

 

[The Chairman]

what about a roll on with nothing at all?

This wouldn't be in anything but OW. Taking a single reg into any overhead environment, is not wise.