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Training my sense of CO2 ppm

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Re: Training my sense of CO2 ppm

#71

Post by elif »

I've been using the uHoo air monitor for the last few months. I have one in the bedroom, living room, and office. It monitors many air factors, but CO2 was my primary focus.

My original goal was to have a fresh air intake activate automatically at certain concentration levels, if the outside ambient temperature/humidity were appropriate.

However, living in a hot humid place, the data I got made that solution seem futile. Ventilation for CO2 alone takes so much air that it becomes basically a full reset on dehumidifying and conditioning.

However, this failure lead me to the fortuitous discovery that by adding 36 hydroponic heads of lettuce, I am now going beyond outside CO2 levels, dipping down to 390-400 and only reaching ~700 overnight when it's the worst.

Re: Training my sense of CO2 ppm

#72

Post by alins »

abirkill wrote: post #42
scottlamb wrote: post #41

Earlier quoted context omitted.

> Unfortunately, when I last looked, I couldn't find any consumer-grade sensors which used dual-NDIR sensors, only more expensive and less aesthetic commercial sensors. In the end I built my own using a CDM7160 sensor connected via I2C to a ESP8266, which reports over MQTT. Looks like that's been discontinued. [1] Any advice for folks trying to build one now? [1] https://www.figarosensor.com/topic/2020/11/Discontinua…

That's a shame, they've worked well for me. Unfortunately I can't recommend any others without doing some research, I found quite a few dual-NDIR sensor modules when I was looking and chose this one primarily based on availability and a reasonable datasheet. A sibling post[1] mentioned a sensor that is listed as being dual-NDIR so should give reliable readings, and has a USB interface, so that sounds like one possibi…

Manual for this unit is at https://cdn.shopify.com/s/files/1/0019/5952/files/Manual-RAD...

I assume 'dual-beam' is the same as dual-channel? Does the calibration technique mentioned in the manual indicate dual channel operation?

Re: Training my sense of CO2 ppm

#73

Post by teruakohatu »

elif wrote: post #71

I've been using the uHoo air monitor for the last few months. I have one in the bedroom, living room, and office. It monitors many air factors, but CO2 was my primary focus. My original goal was to have a fresh air intake activate automatically at certain concentration levels, if the outside ambient temperature/humidity were appropriate. However, living in a hot humid place, the data I got made that solution seem fut…

That I'd very interesting. Is ther data on how much C02 is consumed by lettece?

Re: Training my sense of CO2 ppm

#74

Post by amitamit »

stanislavb wrote: post #53
CoastalCoder wrote: post #7

I think the elephant in the room is calibration of the CO2 detector. When I looked into this a few years ago, I couldn't find any accuracy guaranties for CO2 meters marketed for households / greenhouses. The closest thing I could find were laboratories that could test CO2 meters in chambers with known CO2 concentrations. But IIRC the pricing for those labs was prohibitively expensive. - There were literally no guaran…

I use the same CO2 meter as the author has showcased. It's amongst the most accurate ones on the market at the moment (home grade). It uses a The Non-dispersive infrared sensor (NDIR) which is much more accurate than most sensors on devices sold online for $100-200. In fact, it actually measures instead of "estimates" the level of CO2 (as most cheap ones do).

Agreed!! I have also tried many different CO2 meters (all consumer-grade) and Aranet has been consistently the most accurate among the CO2 meters I have used.

Re: Training my sense of CO2 ppm

#75

Post by Titan2189 »

post-factum wrote: post #3

I've bought [1] and coupled it with Zabbix using [2]. Now I have a pretty realtime graph and a strong reasoning to air my room more often. [1] https://www.tfa-dostmann.de/en/product/co2-monitor-airco2ntr... [2] https://codeberg.org/pf-monitoring/airco2ntrold

Does it allow you to read data via USB or is that just the power supply?

Re: Training my sense of CO2 ppm

#76

Post by CoastalCoder »

amitamit wrote: post #74
stanislavb wrote: post #53

Earlier quoted context omitted.

I use the same CO2 meter as the author has showcased. It's amongst the most accurate ones on the market at the moment (home grade). It uses a The Non-dispersive infrared sensor (NDIR) which is much more accurate than most sensors on devices sold online for $100-200. In fact, it actually measures instead of "estimates" the level of CO2 (as most cheap ones do).

Agreed!! I have also tried many different CO2 meters (all consumer-grade) and Aranet has been consistently the most accurate among the CO2 meters I have used.

How did you determine the accuracy of your CO2 meters?

Re: Training my sense of CO2 ppm

#77

Post by convexfunction »

robocat wrote: post #49
post-factum wrote: post #3

I've bought [1] and coupled it with Zabbix using [2]. Now I have a pretty realtime graph and a strong reasoning to air my room more often. [1] https://www.tfa-dostmann.de/en/product/co2-monitor-airco2ntr... [2] https://codeberg.org/pf-monitoring/airco2ntrold

Amazon link: https://www.amazon.com/CO2Meter-RAD-0301-Mini-Monitor-White/... Artwork slightly different, but appears to be same product: “Using NDIR CO2 Sensor Technologies; Technical Specifications: CO2 Measurement Range: 0-3,000 ppm; Response Time: < 2 Minutes; Accuracy: 0-2,000 ppm ± 100 ppm or ± 7% of reading; Sensor Life Expectancy: 15 years”.

I'm not convinced this is truly the same product. A highly-rated review and some questions seem to say it does auto-zeroing and assumes the lowest concentration seen over some period of time is "outside", which as I understand it wouldn't be necessary if it were dual beam NDIR?

Re: Training my sense of CO2 ppm

#78

Post by taxicabjesus »

h2odragon wrote: post #2

people on supplemental oxygen sometimes get CO2 problems; the oxymeter shows good numbers but they're acting drunk or feeling poorly otherwise. Apparently its sneaky and cumulative; a few moments wont do much but as time goes on you get fizzier.

Supplemental oxygen usually causes hypocapnia (low blood CO2). Adding a little CO2 prevents hypocapnia.

Re: Training my sense of CO2 ppm

#79

Post by bjoli »

saaaaaam wrote: post #54

I have a fantastic way that I’ve trained my CO2 sense: an Italian greyhound. Anything above 900ppm and he barks and gets quite frantic above 1100ppm. I’m now able to anticipate the barking and normally realise at about 850ppm that we need to go for a walk and open the windows. A vet friend theorised that because they have a completely disproportionate and crazy cardiopulmonary system (huge lungs and heart compared to…

On a related note: A friend of mine was exposed to high co2 levels while on a freight ship. He says it is the absolute worst feeling he has ever felt, with panic and convulsions and vomiting. He survived because a colleague of his managed to get him out.

Kinda makes me wonder why it is still allowed in animal slaughter. It is cheap and gets the job done, but there must be better gasses. There are loads that just makes humans pass out, and it must be the same for animals.

Re: Training my sense of CO2 ppm

#80

Post by legulere »

elif wrote: post #71

I've been using the uHoo air monitor for the last few months. I have one in the bedroom, living room, and office. It monitors many air factors, but CO2 was my primary focus. My original goal was to have a fresh air intake activate automatically at certain concentration levels, if the outside ambient temperature/humidity were appropriate. However, living in a hot humid place, the data I got made that solution seem fut…

You need controlled ventilation with heat recovery to have both good air quality and temperature/humidity.
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