Need a little help with my nitrox stick

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Topbodz

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I finally used it for the first time today. I was all excited!!!

but at the end of the day, my mixes are coming out short.


I filled 2 tanks where my new nuvair oxygen analyzer was showing 32.4% going into the compressor intake tube...

end result with an analyzer at the tank (also brand new) I showed 28.5%



I did one tank at 36.5% and ended up with 32.1% ....


where is me oxygen going?
 
500 psi of air already in the tank?
 
are you pumping and then checking with different analyzers?

I finally used it for the first time today. I was all excited!!!

but at the end of the day, my mixes are coming out short.


I filled 2 tanks where my new nuvair oxygen analyzer was showing 32.4% going into the compressor intake tube...

end result with an analyzer at the tank (also brand new) I showed 28.5%



I did one tank at 36.5% and ended up with 32.1% ....


where is me oxygen going?
 
I think we have covered this before... Here is a link to an old thread. Most likely you have some Nitrox analyzer calibration issues.

Please wait

If you do have a leak causing this dilution, it would have to be in the section between the Nitrox Stik and your air compressor intake, the rest of your compressor is at pressure and you would not leak air in... it would leak nitrox out.
 
are you pumping and then checking with different analyzers?

yes. I have a panel mount on the nitrox stick and I check again with a hand held one after the tank is filled
 
Ok use the same analyzer for both readings, or find a way check a like volumn of gas say from a tank of gas being bled into the stick and then check that also with the analyzer AND sensor used for the compressed gas check.

It is not possible with the process you describe to get different readings, hense the measuring device's must be put in question.

One more thought. Do you normally pump air adn are you using the same filter system for both. Explanation,,, If youare using the system for air and your filter stacks are filled with air and you start to pump ean, you will get a diluted out put till the filter stacks get the same ean% as teh stick.

yes. I have a panel mount on the nitrox stick and I check again with a hand held one after the tank is filled
 
Maybe I missed it, but do you calibrate your sticks O2 sensor with the compressor running but the O2 turned off? Set it to 20.9% or so and then turn the O2 on and dial it 32%. Occasionally you can turn the O2 off and verify 20.9%.

I have my regulator flow restrictor valve set so I have around 32psi on the O2 reg to obtain 32%. Very rough number as pressure changes, the mix, but it makes for a good starting point.

FWIW I have a Nuvair CO analyzer mounted inline when I fill too, even though my compressor has never failed me. I have seen first hand a compressor inputting 38% and getting 32% out as the filters were burning up.
 
One other thing that could do this is if your stick isn't mixing well and you are getting a stream of high oxygen air at the sensor. I also second checking the tank with the same equipment you check the input mix.
 
One other thing that could do this is if your stick isn't mixing well and you are getting a stream of high oxygen air at the sensor. I also second checking the tank with the same equipment you check the input mix.


That analyzer comes with a thermistor and pretty much stays in the nitrox stick...


I should get the desired reading using the hand held analyzer...

---------- Post added December 7th, 2013 at 12:28 PM ----------

im using a medical LPM regulator that goes to 15 lpm. That does not seem to be enough for the stick/compressor setup. The stick is the Oxygen hacker's plan and the compressor is a 20.8 cfm.

I can open the oxygen flow valve enough to get up to 38% reading at the sensor....

could my filtering have anything to do with it?

my filters (Lawrence factor) say not to run enriched air through them... wonder why?
 
https://www.shearwater.com/products/peregrine/

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