View Full Version : Pictorial - Connecting two concentrators

01-05-2003, 07:21 AM
Here are some pictures of the necessary fittings to connect two oxygen concentrators together.

This shows a female "B" oxygen to 1/4" hose barb fitting. You will need two of these. I paid about $1 each at my local welding supply store.

This shows one of the fittings connected to the second ox con. Note that I have a chromed right angle connector on my ox con. This is unecessary, I just happened to have one. My hose was a tight fit and the oxygen pressure is so low that I did not need clamps. However, a plastic tie-wrap cinched tightly on the hose would not be a bad idea.

This shows the "Y" splitter. Green hose on the left is going to the torch, clear hose on the right is coming from second ox con. Note that the splitter has valves on it. These are not necessary and just add to the cost of it. I was ordering glass from C & R Loo and the splitters I ordered had the valves. I leave the valves wide open all the time. Make sure you buy an OXYGEN splitter and not a fuel splitter, as the threads are not the same.

On my concentrators (Puritan-Bennet model PB-590), they have internal check valves, so these are not necessary. When you have both concentrators running, use the flow knob on each concentrator to "balance" the flow from each unit. Also, you will find that the two units do not "track" each other at all flow rates, so you might need to readjust the flow rate of one or the other concentrator. I'm usually running about 3-3.5 LPM from each unit on my Nortel Minor, and it makes for a sweet flame.

Any questions, just PM me, I'll try to answer them.


01-05-2003, 11:14 AM
Bill, thanks for the visuals!! I was trying to picture just how this was done, so this helps a lot!!

01-05-2003, 01:11 PM
Very interesting Bill. What would be the reason for doing this?

01-05-2003, 02:16 PM
To increase the volume of oxygen available to torch. It gives better flame characteristics and does not let torch become oxygen starved when bigger flame is needed.


01-05-2003, 02:27 PM

MORE POWER ugh ugh ugh !!!!

(he says in his best "Tim the Toolman Taylor" voice)

In this case more flame = more heat = bigger beads !!

Dale said it best, more oxygen means you can turn the propane up more before you hit reduction, meaning you can work on larger pieces.

(Cheryl - this should go sticky after a few days, it has been asked before)


laughing glass beads
01-05-2003, 02:47 PM
Wow, thank god for the visual, I am just now considering another concentrator. Thanks, Bill! CC

01-05-2003, 09:08 PM
Thanks for the explanation. Makes sense. Bill, will do. :)

01-06-2003, 11:21 AM

I think the brass check valves you are using are "overkill". The ones I provide when someone purchases 2 concentrators are just a silicon flap inside the clear tubing "y" connectors. It doesn't take much pressure at all to open them...no problems with these at all. I sell the setup to people who haven't purchased 2 concentrators for $7.00...that's for "y" connectors and check valves.


01-06-2003, 12:55 PM
Paulette's "Y" splitter and check valves for $7 is a good deal !! My splitter alone cost $20 from C & R Loo.


01-06-2003, 05:25 PM
Originally posted by BillBrach
When you have both concentrators running, use the flow knob on each concentrator to "balance" the flow from each unit. Also, you will find that the two units do not "track" each other at all flow rates, so you might need to readjust the flow rate of one or the other concentrator.

Sorry -- being dense here -- what do you mean by track? I assume that you mean that one concentrator may be working harder than the other, but how would you tell?

I have a 5 lpm concentrator and a 4 lpm concentrator. Would I be asking for trouble if I tried to connect the two?

01-07-2003, 06:25 AM

Yes, you are on the right "track" !! Two units perfectly matched would flow the same proportional rate of oxygen, even when you turned the torch up and down. I have two identical units from the same manufacturer and they DON'T track perfectly. There is an internal pressure regulator, and obviously, in my case, they are not set the same.

BUT, it really doesn't matter, because you leave your torch oxygen set at the same flow most of the time.

All you need to do is adjust the black flow knobs on the concentrators so that both concentrators are putting out an equal amount of oxygen. Emily, in your case you'd probably want to adjust your 4 LPM unit to put out 3 LPM, and the 5 LPM unit to put out 4 LPM. This way, you'd be getting 7 LPM, just about what those really expensive oxygen generators puts out. If you had two 5 LPM units, then you adjust the black knobs so both units are putting out 4 LPM.


01-07-2003, 03:31 PM
This is really interesting stuff. I've sent a copy of this thread to the Glass Class 101 sticky thread.

01-07-2003, 08:08 PM

Do you think it is absolutely necessary to have the check valves. When I set mine up, the welding shop was out of the check valves and I have not had any problems running without them. Is there some damage I could be doing to my concentrators? Is this flap you mentioned something I could add to my Y connector?


01-07-2003, 08:46 PM
Hi Sandy,

I say, "if it ain't broke...don't fix it"! Seriously, if your concentrators aren't whining (the alarm would be sounding) then I wouldn't add them. If I hear differently from my techie tomorrow, I'll post.


01-07-2003, 09:06 PM
Thanks Paulette...they seem to be working fine.


Robert E Thompson
09-28-2003, 02:41 PM
Hey Bill,

Will a couple of concentrators give me enough oxygen for my carlisle cc when I crank it up to do big boro work?:cool:

09-28-2003, 04:28 PM

I don't think two are a enough. Contact Carlisle and see what they list that torch at for LPM (liters per minute). I'd bet that torch needs 30 LPM or more, especially if the center fire is on.

I don't know why the torch manufacturers don't list fuel and oxygen requirements of their torches, it sure would simplify things.


09-28-2003, 05:32 PM
...give me enough heat on my minor to do boro work? On ANY torch to do boro? Even small boro? (less than 1 inch)

Robert E Thompson
09-28-2003, 05:43 PM
Ok thx Bill, I will do just that!:)

09-28-2003, 07:24 PM

I use a Bethlehem Bead burner with two concentrators and it is very hot. Fine for boro beads. I think a Lynx would also work. I have just heard about a new torch that Wale Apparatus has brought out called (I think) the Firefly...please correct me if I am wrong about the name, if anyone knows. I think this is also a smaller torch that can work with two concentrators and do boro.

I hope to get up to Wale sometime and try it out.


09-28-2003, 09:48 PM
I've done boro on a minor before but can't with just one concentrator. I was thinking of going to bottled oxygen but don't want to. Maybe I'll just get another concentrator. Hummm.

This is not a cheap hobby.

09-28-2003, 10:20 PM
I believe this is what paulette is talking about , pl;ease excuse the lousy pics, it's late and my lights aren't all working in the garage studio at the moment.
this is where the two come together to make the one that the torch conects to.
here is an expanded view showing the whole thing
at least this is what I use for my 2 concentrators on my minor, my lynx is on tanks

09-29-2003, 07:02 AM
You can easily do boro on a Minor with one concentrator. You are limited to smaller items, and it is pretty slow to melt. BUT, it can be done. A great way to get your feet wet with boro is to buy Clear, 'cause it costs about what soft glass costs. You can practice making beads and small pendants, without wasting $30-$50 a pound color.

A great INEXPENSIVE torch for boro is the National 3A. I have one of these with an OX-2 tip. These are generically referred to as a "blowpipe" torch and are used extensively in the plumbing trade for soldering of copper pipes.

You should be able to buy one new, from somebody like Wale Apparatus, with the OX-2 tip for about $100. Used, they will go $40 to $60 with the tip.

It doesn't have a large flame, but a very hot one. Don't try it on soft glass, it will burn it before you can say "jack rabbit" !!

Here is a link to the latest model.


09-29-2003, 10:04 AM
BILL THANK YOU SOOOO MUCH! I am planning on Santa to bring me another concentrator this year and this is EXACTLY the info I will be needing!!! This is awesome! I am sure I will be emailing you after I get the second one too, just to be sure I do everything right!

Thank you!!!

06-14-2011, 11:01 AM
8 years after this thread started, I finally need it! Many thanks to all that contributed info on this topic.