CO Analyzer

[49north]

True enough. Thanks for your help on this. I really appreciate it!

 

[Got2Go]

Does anyone have any recent feedback on the Cootwo analyzer? In reading through the threads, it seems like there have been some issues with inaccurate CO readings. This being a new product, I can't help but wonder if there are some bugs that need to be sorted out.

Does anyone have any experience with the Nuvair De Ox analyzer? It is considerably more expensive and the replacement sensors are almost 4 times the price. Is it that much better?

Are there any other analyzers worth considering?

Thanks!

I am guessing you already read here:
http://www.scubaboard.com/community...onsistent-based-on-ambient-temperature.530215

That was just my experience (both with the unit and with DiveNav).
I might be the only one with such issues, so it might just be an outlier case...
I was more disappointed in the interaction with DiveNav, but extremely impressed with DRIS' way of helping out.

It's a cool little device, but I'm still not sure I can trust it (for CO readings, anyway).
O2 seems to be good.

 

[laikabear]

Just another CooTwo user with my 2c... in reference to both the OP and the other thread by @Got2Go

I have mine set to read CO in whole #s not tenths. It generally reads 0 or 1 ppm on a tank, occasionally a 2. Ambient air may go up to a 3, especially if I am cooking (gas stove). But, those are all "acceptable." People who get sick from high CO in a tank aren't sick from 1.8 ppm. I am expecting the unit to save me from getting sick (or worse) by telling me if there is 5+ ppm in a tank. I think it's just not accurate to the extra decimal place. Once you did the testing outside the bag and got only a variance of 0 to 2 ppm (my rounding), I think that's acceptable. Right? There was some discussion of setting it to whole #s rather than 10ths on another thread, but I forget which one.

I have never seen a CO reading over 3 ppm on mine. A more expensive analyzer might be both more accurate and more precise, but I don't know that is necessary for our application. Another thread listed people's personal cut-off for diving a tank. I think 5-10 and I'd be asking for another tank. Anyone else want to chime in with a different opinion?

I have had some issues with CooTwo getting it to calibrate. Sometimes it turns itself off several times in a row when I try to calibrate it. Sometimes it's REALLY hard to get it paired with my smartphone and it fails several times in a row (when I break down and use the phone; I prefer to use it standalone). That's annoying if I'm at a shop and trying to quickly test a tank. Then I get the shop analyzer helpfully thrust in my face (which doesn't measure CO). Admittedly I'm a rather impatient person.

It's hard to get the LP hose adapter ON the CooTwo for me. It's easy to get it OFF by leaving it attached to my BC and disconnecting the CooTwo 1st and adapter 2nd. If I take it off the LP hose first and try to separate them, forget it.

Mine has gone dead twice with no warning. Isn't it supposed to show low battery? Now I'm more careful to charge before a trip.

And finally, I think the instructions leave a lot to be desired. We were promised a PDF instruction manual was coming a few months ago. Still only have the videos on the website which are not very convenient.

But overall I still like the unit and I like that it measures CO too. I find it a bit fiddly but it does the job ok and it was a good price point, and I like only having to have one analyzer. I think CO is really important.

 

[49north]

I am guessing you already read here:
http://www.scubaboard.com/community...onsistent-based-on-ambient-temperature.530215

That was just my experience (both with the unit and with DiveNav).
I might be the only one with such issues, so it might just be an outlier case...
I was more disappointed in the interaction with DiveNav, but extremely impressed with DRIS' way of helping out.

It's a cool little device, but I'm still not sure I can trust it (for CO readings, anyway).
O2 seems to be good.

I did read this thread. I hope you got it sorted out and I hope it was an isolated incident.

Just another CooTwo user with my 2c... in reference to both the OP and the other thread by @Got2Go

I have mine set to read CO in whole #s not tenths. It generally reads 0 or 1 ppm on a tank, occasionally a 2. Ambient air may go up to a 3, especially if I am cooking (gas stove). But, those are all "acceptable." People who get sick from high CO in a tank aren't sick from 1.8 ppm. I am expecting the unit to save me from getting sick (or worse) by telling me if there is 5+ ppm in a tank. I think it's just not accurate to the extra decimal place. Once you did the testing outside the bag and got only a variance of 0 to 2 ppm (my rounding), I think that's acceptable. Right? There was some discussion of setting it to whole #s rather than 10ths on another thread, but I forget which one.

I have never seen a CO reading over 3 ppm on mine. A more expensive analyzer might be both more accurate and more precise, but I don't know that is necessary for our application. Another thread listed people's personal cut-off for diving a tank. I think 5-10 and I'd be asking for another tank. Anyone else want to chime in with a different opinion?

I have had some issues with CooTwo getting it to calibrate. Sometimes it turns itself off several times in a row when I try to calibrate it. Sometimes it's REALLY hard to get it paired with my smartphone and it fails several times in a row (when I break down and use the phone; I prefer to use it standalone). That's annoying if I'm at a shop and trying to quickly test a tank. Then I get the shop analyzer helpfully thrust in my face (which doesn't measure CO). Admittedly I'm a rather impatient person.

It's hard to get the LP hose adapter ON the CooTwo for me. It's easy to get it OFF by leaving it attached to my BC and disconnecting the CooTwo 1st and adapter 2nd. If I take it off the LP hose first and try to separate them, forget it.

Mine has gone dead twice with no warning. Isn't it supposed to show low battery? Now I'm more careful to charge before a trip.

And finally, I think the instructions leave a lot to be desired. We were promised a PDF instruction manual was coming a few months ago. Still only have the videos on the website which are not very convenient.

But overall I still like the unit and I like that it measures CO too. I find it a bit fiddly but it does the job ok and it was a good price point, and I like only having to have one analyzer. I think CO is really important.

I would think that knowing the PPM to the nearest whole number would be sufficient. My understanding of this is that you really just want to know if the contents of the tank is safe or not.

Is the battery user replaceable? In looking at the website, I found the lack of a user manual a bit frustrating.

I'm sure the technology behind gas analyzing is nothing new. That said, with this being a new product, it sounds like there may be some bugs to work out.

 

[laikabear]

I don't think the battery is intended to be replaced by the user. It is charged via USB.

 

[KevinNM]

the Cootwo is perfectly fine, there have been some wonky sensors that have gone out, but have been replaced. No different than any other analyzer since they all use the same sensors. No way I'd spend the money for the Oxycheq when the cootwo is cheaper and does more.... Perfectly happy with mine and per the vast majority that our out there, it is accurate

I had my sensor replaced when it was reading 30. It started reading 9-11 all the time a few weeks later and I sent it back and they said it was fine. It still sees significant CO all the time.

 

[tbone1004]

the sensor issue is something that cootwo can't control though. Oxycheq and everyone else is just as susceptible to the bad sensor batches which is seen in the rebreather world all the time with O2 sensors. Check it against a tank of pure O2 and see if it goes down. If it does, then you may just have a high level of ambient CO in the air.

regarding the battery, it is not intended to be replaced as it is a rechargeable li-ion battery, but it can be replaced if needed

 

[DiveNav]

Will the unit still function if the CO calibration expires?....

No.

....How much does it cost to get reference gas and a regulator to calibrate yourself? Where do you get this?

There are several vendors offering CO calibration gas and regulators.
One of them is --> Carbon Monoxide Calibration Gas Blend - BuyCalGas.com

 

[DiveNav]

@DiveNav ....(I'd also like to know what is the recommended CO/Air mixture (% or ppm) for calibrating)

20ppm. It is indicated in the app.

 

[DiveNav]

....What would you use for the 0 PPM part of the calibration? Could you use pure oxygen or would that somehow mess up the O2 sensor?

Pure O2 is fine.
Also a know gas that has 0 ppm is fine too.