Help. please! Problem with concentrators and/or holding tank
 

I have two EX-15's hooked up with a T connection through a holding tank (years ago, we used Trey Cornette's directions to set it up, but I've long since lost those directions). It's been working great for 3 1/2 years. The concentrators were purchased through ABR and are less than 4 years old.

Just recently, my concentrators have been cutting out. Technically, I don't know what terms to use to describe it. I'll be torching for an hour or two, and all of a sudden one of the concentrators starts thumping loudly, the ball drops on the gauge, and my flame chemistry goes to shit.

The thing is, it's happened with both concentrators, so I don't necessarily think it's one concentrator going bad. DH cleaned the filters, checked for leaks on all the hoses etc. and no leaks, filters are cleaned.

If we leave just one concentrator on (either one) with the holding tank, the concentrator runs just fine. But of course, that doesn't give me sufficient oxy to run my torch properly. When we turn them both on, after a minute or two, the thumping starts in one or the other concentrator - no apparent rhyme or reason for which one.

Any help, suggestions, ideas, are much appreciated!!!

Sorry Rene.

Nothing jumps out to me.


I do know that my medical grade units have a coarse filter and fine filter on the input as well as a third "bio" filter on the output to prevent microbes from making patients sicker than they already were.

Any chance the "bio" filters might have reached the end of their useful life?

Wish I had an answer for you.

Hi Phill, Hubby says he checked all the filters. He does have an idea of something else to try, but until he does I guess we won't know if it solves the problem. Hoping he will be able to try his idea soon. Just the idea of not being able to torch is making me stressed!!

Any chance of getting a tank of O2 to get you through the repairs?

Probably not cost effective.


Maybe a Craigs list hunt for a backup oxycon perhaps.

Or an old welders kit.


Good Luck.

To paraphrase an old saying from my hippy days ;

Glass will get you through times of no money better than money will get you through times of no glass.

Funny, all I had to do was replace two r's with two l's.
Maybe I knew more than I realized back in those daze ! :lol:

Love the paraphrase! :lol:

It sounds like there may be a bad check valve and when running both concentrators you are back pressuring the other

My hubby put check valves in both hoses after reading up on it a bit, and we "thought" that fixed it. But nope. About 90 minutes into a torch session, same thing happened. :(

They aren't old concentrators - maybe 3 years old, but I don't get a lot of torch time so they don't have a lot of hours on them. I bought them from ABR. If I can't figure it out soon, I guess I'll be buying new concentrators at the Gathering/Glass Craft. Hopefully ABR will be there with some!

Is your holding tank large enough to accommodate two EX-15s? If you are putting more oxy in the holding tank than you are using it might not allow the newly made oxy access. Just a thought. Did you use the tank size recommended in his directions or move up in size. The recommended sized worked well for me with one 5 lpm. There was a noticeable difference in the consistency of my flame. I've not hooked my 2 M-15s to it because I thought it might be too much for the tank size.

Not sure what torch you run. Does it happen when you are running the torch full out like when blasting a large boro gather? Or are you running a large torch with a smaller controlled flame that wouldn't need as much oxygen? I can't help but think you are making more than using and there is way more going into the holding tank than coming out.

If your torch has an inner and outer ring, while using just the inner you could keep the oxy open on the outer to see if bleeding off a bit of extra oxy helps.

I've been using these concentrators for roughly three years with the holding tank and always had good flame chemistry, no issues etc. I am using a GTT Cheetah (15 port) and this set up runs the torch well.

All of a sudden one day after I'd been torching for about 2 hours, one of the two concentrators started making a loud thumping noise - similar to the noise your washing machine makes if the load is unbalanced. The pressure dropped and so I immediately shut them both down. Checked the filters and they were a bit dirty, but nothing horrible, so cleaned them.

A few days later, I decided to try again, hoping it was just a fluke. Again, concentrators ran well for a period of time - I think about an hour to an hour and a half, and then the same thing - thumping and loss of pressure.

Hubby came in and piddled around with them a bit, tested the hoses to make sure I didn't have any leaks, checked the holding tank, etc. Then he read up on it and decided to put the check valves in. We did that, and I hoped that would fix it, but nope - same issue - runs for a while and then boom. :confused:

The weird thing is, it appears that BOTH concentrators are doing this - not at the same time - but one OR the other will start thumping and pressure will drop. After the 4th time, both of them did it, one right after the other.

I find it odd that both concentrators would go out at the same time (I think one is 5 or 6 months older than the other, (both bought from ABR - Extreme Oxygen devices). So I keep hoping there's something else causing the problem and it's not the concentrators dying on me. But I don't know what else to check.

The run/start capacitors. a $10-$15 part but DONT TOUCH THEM IF YOU DONT UNDERSTAND THEM.

They hold high voltage even when unplugged and will whack you.
Get someone who is a geek.

Thank you! I "think" I just found someone who works on concentrators, so I will ask them if they 1) have a source for parts and 2) know how to replace this part.

Again, thanks for the info! I hate to spend a ton of money buying new concentrators if there is a potentially easy fix!

Electric motor repair shops can do this for you too.


If it is the capacitor it should be a simple matter for them to swap it out with a new one.


Capacitors can go bad over time and exhibit this kind of intermittent behavior and it wouldn't be unusual for two machines to come up with similar symptoms pretty much at the same time.

The oxycons are mostly an air compressor that pressurizes two tanks one at a time with a material the soaks up nitrogen leaving oxygen behind and that pressurized oxygen is then routed to the torch. Then the thing shifts over to the other tank and cycles back and forth between them so you have a near constant supply of oxygen.

This capacitor just works with the compressor motor so it is a fairly simple repair for someone with casual motor repair experience.

Just make sure they don't decide that anything other than the motor needs to be oiled. That could prove to be an explosive mistake.
The motor probably has sealed bearings that don't need to be oiled either.


Good luck and let us know what you learn.