Any suggestions for CO2 sensor in high RH environment?

Hardware
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1

I have an MH-Z19B CO2 sensor, and the datasheet says it’s designed for 0-90% RH. Suggestions?
Should I just spend some money and feed this sensor air remotely with a pump like in the Mycodo Mushroom Automation writeup?
Also, I’d like to donate to your cause, Kyle. Where can I do that?
Please and thanks

2

I believe you can do that from here.

Moreover, could you explain a little bit more about what to ask for advice on?

3

I’m concerned about it being in a high humidity environent and wondering if I should get a different sensor (guess i could just search), or feed this one samples from the room via tubing.

4

As far as I know, you shouldn’t be exceeding %90 Humidity in your environment due to the safe VPD rates. So, this sensor would suffice your needs unless you consider growing production-level qualified plants.

5

He’s likely growing mushrooms if the environment is above 90% humidity. I’d say the MH-Z19B is sufficient in a 90% - 100% humidity environment, but I would not approach 100%, since saturation of the air causes condensation and this can cause issues with electronics and possibly the optics in the sensor. In any case, operating the sensor in a high humidity environment continuously is not a great idea. For long-term use, I would recommend creating a sampling chamber that draws air from the grow environment into the sampling chamber for measuring. You could take this a bit further and introduce a second air pump to draw fresh air into the sampling chamber (after the initial sampling is complete) in order to remove the high humidity air and extend the life of the sensor.

Another option, although much more expensive, is the Atlas Scientific CO2 sensor, which specifies it can handle 0 - 95% non-condensing humidity. I think the MH-Z19B could handle the same, since it uses the same NDIR sensor type. The only difference is that most of the circuitry of the Atlas sensor is potted (sealed in epoxy) and isn’t susceptible to moisture issues. The main drawback for NDIR sensors is humidity can affect the CO2 measurement, however this can be corrected if humidity is measured by the device for correction, such as the SCD30 (actually, possibly not, since I don’t see it specifically documented in the datasheet).

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