I’m searching for CO2 sensor with 0-10000 ppm range
I found DFRobot SEN0220 (https://www.dfrobot.com/product-1565.html), but sadly I can’t find any information will it work with ESPHome.
It’s a bit expensive (around $90), but has good accuracy.
Did anyone use this sensor in ESPHome? It is UART based, so maybe there is other (manual) way of using it.
Can someone recommend an alternative? I looked at MH-Z19C, but I can’t find good information about the reading range.
SenseAir S8 seems good, but Can’t find a good source to order a good working sensor.
I plan to use Olimex POE board with 3 PT100 temp sensors and CO2 Sensor.
hmm…before I order the sensor.
The extended range is something you set via the code? Or do I must search for a specific version of the sensor?
How to enable that range?
I’ve also been happy with S8’s from Ali Express. Auto calibration seems to work well. You can visibly see in plots of the data when it does the adjustment.
I bought from this seller.
It’s crazy to see how high C02 gets with two people in a bedroom with the door closed without good ventilation.
AU$34.39 15%OFF | new and original senseAir S8 004-0-0053 S8-0053 infrared CO2 carbon dioxide sensor S8 0053 https://a.aliexpress.com/_mOVIbXW
While we’re at it: how about CO (carbon MONOxide) sensor for esphome? Currently i have MQ7, but all sources say that it’s quite bad… any good quality suggestons ? I guess that combo co2+co woul dbe even better option…
How does the S8 compare to the SCD30? I’ve been testing the SCD30 over the past week and the CO2 measurement seems to correlate more closely with the temperature in the house rather than the occupancy.
I have a MH-Z19D and after a few weeks the measured values got mad (1000 ppm changes in a few minutes). Can’t recommend it.
I have two SCD40 and one SCD41, one of the SCD40 stops working after a few days, the other two are working fine. All three show reasonable values.
Heard good things about the S8 …
Do you really need a 10000 ppm range? I’m measuring in my rooms and very rarely get over 2000-2500 ppm …
I find to get near / above 2000 you need to have two people in a smallish sealed room ( say bedroom). Door closed, good window seals etc.
I live in a relatively modern apartment which is quite well sealed which is good for HVAC heating/cooling but the ventilation hasn’t really been thought through so well.
I tapped into the inline fan in the bathroom and booster fan for the kitchen rangehood to help changeover the air in the place when required. Plus automatic opening of one window. Works well.
Be careful with such “recommendations”. As soon as you try to start searching for scientific proof why that specific >1000 ppm is unhealthy, it gets “thin”.
In this specific picture it’s even worse. Earths atmosphere has a typical CO2 concentration of 420 ppm. Implying that <400ppm is Excellent is bullshit, with normal ventilation you will NEVER get below that 420 ppm value of the atmosphere …
To get a first idea its ok, but try to get such recommendations from different institutions (they will differ) and come to your own conclusion. On my own private scale, values up to 1000 ppm are green …
Just to give some context for folks, CO2 is used as a PROXY for determining if spaces are occupied by people and should be ventilated (for odors and contaminants); in a normal situation there aren’t health risks associated with higher levels. Any symptoms (sleepy, headache, etc.) you might experience when CO2 levels are higher than outside are due to other contaminants in the air, not the CO2 directly. The kind of levels you’d have to get to where CO2 itself becomes a problem are much higher than you’re typically going to experience in say, a house or apartment. As a baseline/reference, OSHA (Occupational Safety and Health Administration, the federal agency in the USA that regulates safety in workplaces, mainly construction & industrial) has an upper limit of 5,000 PPM AVERAGE over 8 hours.
As a Mechanical Engineer, I’ve frequently seen people (including fellow engineers) get concerned about CO2 levels when spaces are ventilated based on it (especially in schools), not understanding that it has nothing to do with safety or health related to CO2 exposure but rather ensuring only the minimum amount of outside air is brought into the space as needed (conditioning outside air takes A LOT of energy).
Not that there’s anything wrong with measuring CO2 in your house. I’ve considered doing so myself ‘just because’, but I’ve settled on a quality PM sensor alone as I feel like this gives me a better metric of ‘how dirty is the air’.
The CO2 seems to correlate good to the “human evaporation” vs. the ventilation done, so it’s good to indicate how “fresh” the room air is or sleepy/headache you may get. If I stay in a room and don’t open a window, the CO2 value will “steadily” go up. Once I open a Window, the CO2 is going down noticeably.
However, the PM will indicate how polluted the air is with particles - that’s a different thing. If I stay in my room the PM stays the same or even goes down a bit. If I open the windows, the PM will even get a bit up in my rooms (seems the outside air is slightly more polluted than my indoors)! When I had a small “microwave fire”, the PM was high for a while …
I’ve also tested some (T)VOC sensors, but they seem to react mostly on specific gases. The SGP30 is good at detecting when you have a beer as it detects ethanol
Yeah I’ve seen they vary a fair bit. Just picked this one somewhat randomly.
I went with some values from a national standard as a bit of a guide for my actual values.
The AU standard is similar. Although they mention some evidence of wellbeing impacts above 1000.
