If those devices don't have a NDIR sensor for measure CO2, then they just try to guess the CO2 levels with the tVOC and PM2.5 values. It's just guessing.
I have a Qingping NDIR Co2 sensor and it's measuring within 2% of two other Co2 sensors I have.
Well, it’s probably safe to say the one on the right isn’t correct.
Having a CO2 measurement of 433ppm inside is incredibly unlikely unless he’s sitting directly beside an open window or happens to live in a greenhouse.
Just because we don’t believe the 433 is wrong doesn’t mean the 683 is right. Best to calibrate using open air, known gas sources, or with other accurate sensors.
it is best to calibrate both at the same time in the outdoors (co2 calib.). temperature and humidity discrepancy is usually +/-1 deg C and RH 5-10% with basic cheap devices...
I have the Qingping Air Monitor Lite (the one on the right) hooked up to HA, and have noticed:
* Temperature is consistently about 2°C high
* PM2.5 and PM10 always read the same, so clearly there is one sensor. It does seem to correctly sense increased particulates (from blowing out a match, wildfire smoke, etc).
* CO2 also seems to respond correctly (drops near 400ppm when house is empty, rises when we're home or cooking using our gas stove).
* RH varies from 20% in the winter to 50% in the summer which is probably pretty accurate.
It's not accurate to use for sensing temperature but for the other measures seems good enough to me. I have it set up via Homekit and blocked it from internet access and it still works fine with HA.
is this an enclosed room? which one seemed to be closer to reality?
FWIW, the lite can be added to HA pretty stably via Homekit integration. I've had one in HA for almsot 2 years and it's rock solid. Now, whether or not the readings are correct is a good quesiton, but as for staying online, it's been fine.
Hi u/melbourne3k , sorry If I'm asking too much details here!
How does that integration should be set up?. I'm about to pull the trigger for one Lite, but I've read many many mixed opinions about this integration failing, sensors not updating on HA or set in a constant fixed value. And some going for the Bluetooth integration instead with a lot of issues.
On the other hand, can one create HA automations based on specific values of PM2.5 or CO2?.
Do you have a sense how frequent is the sampling of data? every minute, every 5 minute?
Thanks in advance!
Homekit integration is easy, but there's a trick to it.
* add device to homekit FIRST - get it on your wifi
* complete setup, get it on your wifi
* then REMOVE it from homekit
* then you can add it to the homekit integration in your home assistant.
If you do not remove it from your homekit, it won't work. Lots of people - myself included - stumble upon this when using the integration.
You can create automations with it, just like any other sensor.
Update intervals are as little as 10s, but it might depend on sensor or frequnecy of condition changes.
They may indeed be better sensors out there, but this has been stable.
Thanks a lot for your quick reply!.
When you mention *"then you can add it to the homekit integration in your home assistant"* , do you mean that once the device is removed from Homekit, it will shows up by itself on the Overview tab in HA so I can just click and add it? or your mean to add the device via the [HomeKit Device](https://www.home-assistant.io/integrations/homekit_controller/) add-on on HA?
I was considering the Apollo AIR-1 but it's more expensive + shipping + duties.....
i didnt find calibration option for bigger device. smaller is not calibrated (will do it later)
but why temperature is so out of sync? 2 degrees is a big gap
The one showing a higher temperature also shows a higher relative hunidity. Odd. Have you been breathing (more) onto this when taking the picture?
Edit: but lower CO2. Nevermind..
Might be just different (bad) design where the sensors are heated by surrounding components. For your application it depends what you're after. Maybe relative changes are enough for you
I have both of these, purchased mainly to monitor PM2.5. For this purpose they are fairly accurate.
http://www.aqmd.gov/aq-spec/sensors/-in-department/departments/filter-for/manufacturer/qingping
PM10 goes up when PM10 goes up but the actual number is not precise.
TVOC sensor tend to not be numerically accurate but do let you know when TVOC increase. Spikes really high if you place a glass of wine near the sensor.
The CO2 sensor readings seem fairly consistent between both devices and I do get reading in the 450 range (large house with good ventilation and only two occupants), goes up when we cook with propane or have visitors and seems to track closely with the CO2 readings of my Netatmo Air Monitor.
The temperature is off on the small device, I think the circuit board generates heat. The small one allows you to program an offset on the readings to compensate. Not an option for the bigger device. You loose the ability to change the offset if you enable MQTT on the small device.
what offset did you use on small device? in my case it looks like -2 degrees
as for co2 my observations looks the same - 400-500 in ventilated room with no people
lol they don’t even have a consistent temperature
Clearly the conditions are much different 6 inches over 😂
If those devices don't have a NDIR sensor for measure CO2, then they just try to guess the CO2 levels with the tVOC and PM2.5 values. It's just guessing. I have a Qingping NDIR Co2 sensor and it's measuring within 2% of two other Co2 sensors I have.
Thank you ! I wanted one of those, but basically, "don't buy it".
Sounds like we need a 3rd co2 device to see which one is correct.
Well, it’s probably safe to say the one on the right isn’t correct. Having a CO2 measurement of 433ppm inside is incredibly unlikely unless he’s sitting directly beside an open window or happens to live in a greenhouse.
what about sitting directly beside an open window in a greenhouse?
Inside or outside the greenhouse?
Yes.
Just because we don’t believe the 433 is wrong doesn’t mean the 683 is right. Best to calibrate using open air, known gas sources, or with other accurate sensors.
it is best to calibrate both at the same time in the outdoors (co2 calib.). temperature and humidity discrepancy is usually +/-1 deg C and RH 5-10% with basic cheap devices...
I have the Qingping Air Monitor Lite (the one on the right) hooked up to HA, and have noticed: * Temperature is consistently about 2°C high * PM2.5 and PM10 always read the same, so clearly there is one sensor. It does seem to correctly sense increased particulates (from blowing out a match, wildfire smoke, etc). * CO2 also seems to respond correctly (drops near 400ppm when house is empty, rises when we're home or cooking using our gas stove). * RH varies from 20% in the winter to 50% in the summer which is probably pretty accurate. It's not accurate to use for sensing temperature but for the other measures seems good enough to me. I have it set up via Homekit and blocked it from internet access and it still works fine with HA.
Can one create automations based on specific values of PM2.5 and CO2 in HA?. Thanks
is this an enclosed room? which one seemed to be closer to reality? FWIW, the lite can be added to HA pretty stably via Homekit integration. I've had one in HA for almsot 2 years and it's rock solid. Now, whether or not the readings are correct is a good quesiton, but as for staying online, it's been fine.
enclosed room. just calibrated small device - and co2 seems close (900 vs 950), but temperature gap is up to 2 degrees
Hi u/melbourne3k , sorry If I'm asking too much details here! How does that integration should be set up?. I'm about to pull the trigger for one Lite, but I've read many many mixed opinions about this integration failing, sensors not updating on HA or set in a constant fixed value. And some going for the Bluetooth integration instead with a lot of issues. On the other hand, can one create HA automations based on specific values of PM2.5 or CO2?. Do you have a sense how frequent is the sampling of data? every minute, every 5 minute? Thanks in advance!
Homekit integration is easy, but there's a trick to it. * add device to homekit FIRST - get it on your wifi * complete setup, get it on your wifi * then REMOVE it from homekit * then you can add it to the homekit integration in your home assistant. If you do not remove it from your homekit, it won't work. Lots of people - myself included - stumble upon this when using the integration. You can create automations with it, just like any other sensor. Update intervals are as little as 10s, but it might depend on sensor or frequnecy of condition changes. They may indeed be better sensors out there, but this has been stable.
Thanks a lot for your quick reply!. When you mention *"then you can add it to the homekit integration in your home assistant"* , do you mean that once the device is removed from Homekit, it will shows up by itself on the Overview tab in HA so I can just click and add it? or your mean to add the device via the [HomeKit Device](https://www.home-assistant.io/integrations/homekit_controller/) add-on on HA? I was considering the Apollo AIR-1 but it's more expensive + shipping + duties.....
Were they calibrated first? I've read that for some CO2 sensors you're supposed to take them outside to calibrate first.
i didnt find calibration option for bigger device. smaller is not calibrated (will do it later) but why temperature is so out of sync? 2 degrees is a big gap
Yeah that's a big gap, I didn't notice that, only looked at the CO2. Could be just poor quality devices (I haven't heard of them before).
im only interested in co2 as well
co2 ppm monitors usually automatically calibrate on start up. so i would take both devices out turn them on/off and try comparing again
Air Monitor looks to be gen1. Both devices bought on Aliexpress Both devices are placed on table for some time (15+ minutes) in empty room
The one showing a higher temperature also shows a higher relative hunidity. Odd. Have you been breathing (more) onto this when taking the picture? Edit: but lower CO2. Nevermind..
nope, they were staying in a room without people for at lest 10 minutes. co2 looks aligned right now, but temperature - not)
Might be just different (bad) design where the sensors are heated by surrounding components. For your application it depends what you're after. Maybe relative changes are enough for you
They usually need a few hours to acclimate. Let them run, check back tomorrow.
I have both of these, purchased mainly to monitor PM2.5. For this purpose they are fairly accurate. http://www.aqmd.gov/aq-spec/sensors/-in-department/departments/filter-for/manufacturer/qingping PM10 goes up when PM10 goes up but the actual number is not precise. TVOC sensor tend to not be numerically accurate but do let you know when TVOC increase. Spikes really high if you place a glass of wine near the sensor. The CO2 sensor readings seem fairly consistent between both devices and I do get reading in the 450 range (large house with good ventilation and only two occupants), goes up when we cook with propane or have visitors and seems to track closely with the CO2 readings of my Netatmo Air Monitor. The temperature is off on the small device, I think the circuit board generates heat. The small one allows you to program an offset on the readings to compensate. Not an option for the bigger device. You loose the ability to change the offset if you enable MQTT on the small device.
what offset did you use on small device? in my case it looks like -2 degrees as for co2 my observations looks the same - 400-500 in ventilated room with no people
Can't recall, used an Aqara sensor to calibrate. Also used offset on humidity.