Air quality sensor for CO2 and Radon?

[trallan (karl)]

I want to keep track of my indoor air quality. Does anyone know of a decent CO2 and Radon sensor that uses zigbee or wifi connectivity?

[orange-assistant (the real one)]

This looks like a possible candidate:

AirThings Wave Plus tracks radon (24h and long term), airborne chemicals, CO2, temperature, atmospheric pressure and humidity.

AirThings BLE Sensors

Can be integrated to HA via wifi using a esphome node configured as bluetooth proxy

Bluetooth Proxy

[dproffer (David Proffer)]

I am only familiar with the CO2 half of your monitoring. However in that domain, I searched of a long while to find a reliable sensor and I had to go to a BLE based device to find something that delivered accurate and useful data. For anything dealing with important health monitoring, IMHO you want something that has a vendor that stands behind the device’s measures and unless you are qualified in the health science of the sensors domain, you don’t was a ‘homebrew’ device.

So long winded route to my recommendation, the ARANET4 device. I have two for two plus years and they are very good. Good hunting!

Cheap Zigbee CO2 sensors any good?

The world of sensors and the quality of the data they provide is a real wild west! I’ve spend too much time and money trying to ‘get a good solution’ in many sensor domains, and I am pretty sure I continue to be far from a solution. That said, at my current state (read that as drawer full of devices). For CO2, I am using the Aranet4 bluetooth units, link below. They are pricey, but on my rant, they defend their solutions with at least some research. For temperature and humidity, I have stayed…

[trallan (karl)]

“Can be integrated to HA via wifi using a esphome node configured as bluetooth proxy”

Not familiar with esp. What does this even mean?

[trallan (karl)]

Yeah isn’t it weird that there aren’t more options?

I found this Tuya that measures CO2 but im not sure how reliable it is.

https://www.amazon.de/Quality-Monitor-Formaldehyde-Temperature-Humidity/dp/B0BS6K3T6Q

I already have. Bluetooth on my NUC that I use for HA. Would it be possible to connect bt sensors directly to that somehow? Also bt might not reach the area I want to measure either.

[orange-assistant (the real one)]

@trallan

Not familiar with esp. What does this even mean?

This means while the sensor suggested is not zigbee or wifi as requested (but bluetooth) it can still be easily integrated into HA with the help of a $5 esp32

ESPHome Bluetooth Proxies

Bluetooth technology has a limited range. Home Assistant can expand its Bluetooth reach by communicating with Bluetooth devices through Bluetooth proxy devices powered by ESPHome.

ESPHome Bluetooth Proxies

@trallan

Also bt might not reach the area I want to measure either.

Dang If only something like a bluetooth proxy would exist

[trallan (karl)]

Ah ok, but I already have Intel Bluetooth I think, that won’t work? This eap thing connects over usb?

[orange-assistant (the real one)]

@trallan

Ah ok, but I already have Intel Bluetooth I think, that won’t work?

Maybe - maybe not… might not reach the area like you said

On the other hand no idea if HA supports that AirThing or if support is only available in esphome

@trallan

This eap thing connects over usb?

This esp typically connects over wifi but ethernet is also available

[trallan (karl)]

Alright, thanks. Then I might look into using bt instead. Just a bit annoying to add a new thing to connect and everything. Maybe I will just get a dumb sensor instead. Seem to cost around 30 dollars.

[trallan (karl)]

I just found a used airthings sensor so I bought it. Gonna see if I can get it working with HA. If not, its still fine I guess. I just want to check that my ventilation is working, I might do that and then just resell it. Though it would be nice to increase my vent for example if a high CO2 is detected. But I currently don’t have any data.

But yes, esp is proably requirerd: Integrate Airthings Wave Plus with Home Assistant using ESPHome

[dproffer (David Proffer)]

Yes, the bluetooth distance thing is something you need to factor in. There are some pretty handy and relatively easy ways to extend your bluetooth ‘envelope’. I use this project to get good coverage around the house:

https://docs.openmqttgateway.com/

To the Tuya sensor that you cited, I think the issue with this one and most of the low cost units is that they use a ‘derived’ CO2 (and I think for their other VOC reading as well). Back to my rant about getting reading that are of high quality, from my research, this method does not yield very useful and accurate reading. Unfortunately, to get a sensor that directly reads CO2, the price of the device goes up. As you see with the Aranet4 device, pricey. And again, look for vendors that back their product with research. My other rant/finding is on the number of measurements you get from a device per ‘period of time’. For radon, I am thinking that several reading per hour would be acceptable, as as I understand the source of the pollutant is your house and soil, the requirement to ‘change’ the air in a space is at a lower rate. However, for CO2, this gas is generated at a much faster rate by human breathing, stoves, heaters and such. So you need a device that will generate CO2 measurement a number of time per minute, this is where I found most zigbee devices to fail. They often do not publish reading very often in order to maintain a long battery life in the device, this results in reading rates that are not useful to alert on high CO2 levels and start air exchange. The Airnet4 device generates reading at a rate where you can see people enter and leave a room, see a stove or heater turn on within a minute of the even occurring. Even with the Aranet4’s higher reading rate, the battery life of my two device have been well over 1 year between battery changes. The other handy feature of this bluetooth device, is if you travel, you can take it with you and get a sense of the air exchange in hotels and airplanes . Good hunting!

[billatq (William)]

You can get the MH-Z19 NDIR sensor fairly inexpensively these days and it works great with ESPHome. The biggest issue with a lot of gas sensors is that they require periodic recalibration. This can either be done manually or by having time where they are exposed to outdoor CO2.

Radon is harder. I use a BLE with a RadonEye.