cootwo oxygen sensor lasts for less than 1 year

[68raggtop]

Mine was 2+ years old and working fine until I dropped the Cootwo on the boat on the first day of the trip last month. Two bad things happened then. The tabs that connect the + and - of the battery bent so the the battery could no longer power the device. After I got back to the room, I re-bent the tabs so it had power. First thing I saw was it needed CO calibration. It no longer had the CO data so it needs a new CO calibration. Using the app, I set it to try and use as O2 only mode until I can do that, but when I went to calibrate the sensor was only outputting around 7mv instead of the usual 12mv. Fortunately I have an abundance of those that came from my rebreather and swapped it for one of those once I got home. No Cootwo for the remainder of the trip though.
Bottom line is don’t drop your Cootwo!
Also as tbone1004 said, when analyzing higher O2% gas, the app will let you do a 2 point calibration.

 

[68raggtop]

wait. if an oxygen calibration lasts for several hours only, does it mean that I will have to calibrate the cootwo on some "reference oxygen" tank before analyzing the "actual breathing oxygen" tank, every time I need a high O2 % gas mix?
that makes no sense to me.

You can change how long the calibration is valid for, up to 48 hours max using the app. 48 hours is the max though, unless someone found a way around that.