Nitrox analyzers - Top pick?

Since we started trimix diving, I've used Analytical Industries' TruMix 4001 and it's been very effective and very easy to use for both nitrox and trimix.

Before that for O2/nitrox testing, we used OxyCheq's El Cheapo II analyzer kit. It's just $110 and includes the $80 sensor. If you add the Expedition flow restrictor it's still just $150 total. It's not hard to assemble if you're handy with tools. We put our in a waterproof box from Underwater Kinetics which keeps it neat, clean, and protected. If you add their $4 sensor saver the R17D sensors will last about 4 years. We still have one for a back up.

 

Looking at a replacement for a damaged Analox OEII, has anyone done a direct comparison between the Analox and Palm analyzers? I can no longer find aftermarket sensors for the Analox (I heard last year they were threatening legal action on aftermarket sellers) and am considering the Palm going forward.

 

@DiveNav - why is the life of your O2 sensor only one year ?

And why does the cootwo force replacement of the sensors on a fixed timescale? If the unit is not being used frequently then this is excessive.

 

I have had the Palm 02 for a year. I just got a Palm CO and used it on a trip to Cozumel. Both work great and are easy to use.

 

Oxyhacker's El Cheapo (several of them). Oxycheq sells them now, easy to build and use. Last forever.

 

The Palm website gives an expected life for the O2 sensor of 42 months = 3.5 years. Thats a lot more cost effective than replacing O2 sensors every year with the cootwo

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I should also add that the Palm analyzers have great support, both from Dive Gear Express and Analytical Industries.

I called Analytical Industries a couple of times with questions and got to talk to a very knowledgeable tech right away. One time I called they said their tech was at the DEMA show. They gave me his cell number and he was happy to answer my questions. Can’t beat service like that!

 

I conducted a lot of research before purchasing a Cootwo. I had high hopes, but was ultimately let down. When I first turned the unit on there was a bright vertical line on the left-hand side of the screen like a broken Gameboy. I’m guessing the screen just wasn’t lined up in the unit correctly. To be picky, the yellow sticker on the front overlaps the clear window for the LED. When pressing the buttons I thought there would have been a quicker response. Sometimes when clicking on the single button to go through the menu options I would have to press the button several times to scroll through. Imagine pressing the button seven or eight times to get to the fifth item on the list. I thought for $50 for a LP hose adapter and a carrying case that the case would have been waterproof and airtight. It’s certainly not. I’m sure I’ll sound picky by saying this, but the Cootwo has a triangle shape when looking down at it, not rectangular, but the padding on the case is rectangular so the unit doesn’t fit flat in the case. Also, if you try to set it flat in the case, the molding isn’t cut right for it. The LP adapter doesn’t have threads on it like the MaxO2 or the Palm D (which use the same threads). Instead it pops on and off. I haven’t tried it to see how snug it is because there is grease on the inside of the LP adapter. So if I use the adapter and then take it off there’s going to be grease on the knob part of the analyzer. Do you really want that in your case? I would like to think the grease is oxygen compatible since I was planning on using this unit with 50% nitrox and oxygen, but if it’s not, I certainly don’t want it touching my DIN valves. Just a clarification from the company would be nice. For $350 you don’t receive a cheaply printed manual or even a disc. You’ll receive a business card with a link to the manual, tinyurl.com/cootwo-manual. After purchasing the analyzer I learned that if the battery dies you might not be able to recharge it at all. Also, if the battery dies, the CO sensor looses (the manual’s spelling of the word) its bias. So if your battery dies, you’ll need to re-calibrate the sensor, if you can get it to turn on. I also read online that if you accidentally drop the device the CO sensor easily pops out and therefore you’ll have to re-calibrate. And last, I read on ScubaBoard that if there is a firmware update you have to mail the analyzer back to the company for the update. You can’t do it yourself. I’m actually sad that things didn’t work out between me and Cootwo. I think the concept of this analyzer is great. Maybe future models will be of better quality.

 

Hi,
Thank you for purchasing cootwo and for your report.
Unfortunately you report includes several incorrect and misleading statements. Please see below.

Li-Ion batteries should be kept properly charged. IF a Li-Ion battery is not properly maintained it MIGHT die off - but that is not always the case. We recommend customers to recharge the battery once a quarter (it takes ~1 hour or so).
IF you let the battery die, you can replace it yourself as it is a standard AAA Li-Ion rechargeable battery (it costs a couple of dollars online)

FALSE.
The digital calibration is stored in a flash memory.
If you remove power for a long period of time the CO sensor (it is a chemical sensor) drifts off (it appears as it lost its calibration). Once you re-apply power (after power was removed for a long period of time) you will need to wait for several minutes (we recommend at least 1 hour) before using cootwo as the CO sensor needs to recover from the drift status (it is a chemical sensor)

FALSE.
This was an issue that happened only on few early models and it was corrected 3 years ago.

FALSE.
There is no need to recalibrate the CO sensor if you remove it for a short time and then re-install it. See above.

Last firmware update was done in May 2017.
If necessary, we update the firmware for free as part of our yearly CO calibration service

Are you saying that the display is defective?
If so, please provide proof of purchase and we will replace the unit as part of our 12 months warranty.

As explained in the manual, HOLD = 2 seconds, PRESS = 1 second.
Use the app if you do not want to press buttons.

As clearly indicated on our online store HERE, the carrying case is not waterproof.

We never received a complain from users concerned how cootwo is sitting inside its carrying case nor we ever received complains that cootwo got damaged while being carried around in its carrying case. cootwo itself said that everything was looking good and comfy.

Yes, the grease used on the inside of the adapter must be Oxygen compatible.

Download the .pdf manual into your smartphone so it is always with you. No need to cut trees. Save the planet.

 

Has anyone tried the CY-12C analyzer from China? Goes for around $90-100 all over ebay and Amazon. Looks pretty foolproof.