Use the same setup as the supported MHZ19, just connect the MHZ14 instead. It works just as well.
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Since the crypto mining with the Awair Element isn’t possible anymore at planetwatch, you can get them very cheap. In Germany you can get a used awair element for ~ 50 €. Sometimes unused Elements for ~ 100 €.
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I have Netatmo, AirThings Wav Plus and AirThings View Plus.
For CO2 they all show similar values, so it’s probably quite accurate.
But for other measurements (Radon, VOC) the tow AirThings, which have been sitting side by side for weeks, show quite different values, sometimes differing by more than 100%.
They all depend upon the cloud, which is a pain, not only because of the latency (10 minutes).
I can hardly recommend any of them, but since there are hardly any alternatives for ready made products, there’s not really a way around them 
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I just ordered an Airthings View Plus - don’t they support BLE + Home Assistant? Airthings BLE - Home Assistant
Yes Airthings does Support BLE, but I did not get it to work properly - please tell when you get it to work
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Maybe we have similar issues - I suspect my bluetooth adapter on my HAOS box is too old or something, or the range is too far.
I ended up buying an esp32 device and using the airthings_ble integration instead: AirThings BLE Sensors — ESPHome - working great!
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do you now get the data in real time or is there still a 10 minute delay?
I discovered another device yesterday: airQ https://en.air-q.com/
they have a lot of (replacable) sensors, but are quite expensive
I did not find a HomeAssistant integration, but they have an API so integration should be possible
Impressive. Looks like a high-quality product (and variants). Quite pricey though…
Here’s the data sheet for those that want to see it: https://support.air-q.com/downloads/air-Q_Specs_de+en.pdf.
What’s nice is that they provide a local API and pushing your data to the cloud is optional. Unfortunately, it seems you need the science variant of the product. This is the top of the range version, which has the most sensors to which additional sensors can be added. It’s also the most expensive.
The air-Q Science Option enables access to the API of the air-Q. Access to the air-Q API is aimed at advanced users with programming experience who want to exploit the functionality of the air-Q to a greater extent. This allows very special configurations to be passed to the device for further communication paths (e.g. HTTP POST to a server or MQTT to a broker).
EDIT: It’s actually a bit unclear. The API docs says that API access is available for the following devices (but except for the science version it’s not the names used on the main site).
- air-Q science
- air-Q Select
- air-Q industry
The data sheet makes it seem like the webserver runs on all versions (under the communication section).
Another edit:
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@bjornb, I have the same question. Does anyone have experience with the Tuya CO2 sensors from AliExpress/AliBaba? I’m considering buying one and comparing it to my Itho Daalderop CO2 sensors, which are very expensive…
@bjornb, the following may answer your question? The quality of the CO2 “guestimations” seems very poor: Notes on Tuya Air Quality Sensors (Electronics, Home Automation) — Kaspars Dambis
FYI, here is the USDA health hazard data sheet for CO2 (with symptoms for threshold exposure levels below vs average outside air levels of ~420 ppm (0.04%)):
5,000 ppm (0.5%) OSHA Permissible Exposure Limit (PEL) and ACGIH Threshold Limit
Value (TLV) for 8-hour exposure
10,000 ppm (1.0%) Typically no effects, possible drowsiness
15,000 ppm (1.5%) Mild respiratory stimulation for some people
30,000 ppm (3.0%) Moderate respiratory stimulation, increased heart rate and blood
pressure, ACGIH TLV-Short Term
40,000 ppm (4.0%) Immediately Dangerous to Life or Health (IDLH)
50,000 ppm (5.0%) Strong respiratory stimulation, dizziness, confusion, headache, shortness
of breath
80,000 ppm (8.0%) Dimmed sight, sweating, tremor, unconsciousness, and possible death
(Our lungs require diffusion gradients between blood and air sacs for both uptake of O2 and expelling CO2 - as @chayerd noted poor room ventilation will typically affect CO2 gradients and physiology long before depleted O2 levels have an effect on us).
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I can recommend Sensirion sensors. I bought a scd41 co2 sensor on aliexxpres, fairly cheaply. And came across an open source project by emariete with ready-made firmware, flashable via the website. All you have to do is connect 4 wires from an esp32 to the co2 sensor. The great thing is that it can communicate with homeassistant via mqtt or the Sensirion integration introduced in the latest version of homeassistant. With a ttgo t-display you also have a screen!
You can also buy a ready made one if you do’nt like diy.
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Qq: Are all dual-channel sensors self-calibrating?
I noticed that the SDC30 SCD30 CO₂, Temperature and Relative Humidity Sensor — ESPHome is also a dual-channel sensor, and yet the documentation says it still needs calibration.
It makes sense that dual channel NDIR sensors should not require calibration, but in that case what makes the T6615 special compared to the SDC30?
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Where are you finding this for $30? I can’t seem to find it anywhere under $100 
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Wow! Prices have gone up. The best price I can find now seems to be the eval kit for $80: Redirect Notice which comes with 2 sensors. Not great if you only want one, but comes with USB serial adapter for testing that is handy.
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I don’t undestand what is exact purpose of second channel in SCD30. Yes the manual and data sheet explain that it has to be exposed to fresh air for the ASC. The Telaire 6615 second channel is used only as reference for calibration and the unit don’t need to be exposed to ~400ppm. That is the exact reason why I purchased this model. It’s been a year and my 2 sensors work fine.
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I purchased mine from Digi-Key Canada
2 units for 124 $ CDN
Thanks for the find! That’s not too bad.
Agree. If the sensor is in a location that is usually exposed occasionally to outside air, the SCD30 is fine. But my T6615 based sensors can go anywhere, and that’s a huge win.
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