Aranet4 Home: Smart Indoor Air Quality Monitor - CO2, Temperature, Humidity, Portable & Battery-Powered, E-Ink Screen, Free App Integration

I picked this up on somewhat of a whim, I read a number of online reviews and it was credited as a very good device but pricy. I have to say it's worth it though. The Bluetooth linking and data storing works really well, I can leave it in-situ for a day or two and then come back and pick up the data to show the trends. Battery life seems excellent (can't comment yet given it's designed to be months to a year) and the unit is ideal sized. I'll admit that it feels somewhat fragile, but then again do you really want to be slinging something like this around. No hesitation, glad I picked it up.

Was looking for a CO2 monitor for some time and this does the job nicely. Being portable means I can have it in my study while I work or move it to the bedroom while I sleep, readings correlate pretty well with when I'm feeling groggy from being in the same room too long without opening a window and it has helped me feel clearer headed. The eink display is pretty easy to read and should mean the battery doesnt drain too fast, It transmits its updates over BLE meaning homeassistant picked it up immediately without needing to be paired. App is straightforward and allows you to adjust a couple of settings as well as update the firmware. And it works locally so no accounts needed for the device or app.

Let's me see how much I need to open my window!

At the beginning I was quite sceptical about this mechanism but as one of our friends highly recommended to have one in our house so we decided to buy it. Very happy with my purchase. It shows the CO2 level, humidity and the room temperature. I started to sleep with open window as the CO2 level was quite high after a night. My quality of sleep improved, I feel more rested. No doubt that it’s very useful. Another interesting fact that we went to one of the castles in Scotland and we spotted the same mechanism in one of the rooms. Probably it proves that it can be trusted.

I've never seen an app for a connected device that's this good. - The app reliably takes only 3 seconds to sync sensor data with the device. Zero connection issues, no faffing about with toggling Bluetooth on/off, it just works, every time. - Easy to use and graphs for CO2, temperature, humidity, and atmospheric pressure. - Everything about the app interface is polished. Setup, firmware updates, regular usage, power-user features, you name it. - The sensor data can be trivially exported in a plain text format. Cons: - To update, the e-ink display needs to flash the entire screen black for a second, it's distracting if the device is within your field of view. - The display does not have any backlight, so to view it in a dark environment you need to either shine light at it or use the phone app.

The Aranet4 is a reliable and high-quality CO2 monitor that integrates seamlessly with Home Assistant, making it a great addition to any smart home setup. It features an E-Ink display, which is easy to read and energy-efficient, although it doesn't provide immediate updates, with readings refreshing every minute. The device updates over Bluetooth, ensuring that your data is always up-to-date without draining the battery quickly, but depending where the hub is located Bluetooth can can a limiting. The Aranet4 uses an NDIR (nondispersive infrared) sensor, which is crucial for accurate CO2 measurements. In a market flooded with cheap, fake alternatives, having a device with a genuine NDIR sensor is essential for reliable readings. While it's a bit on the expensive side, the device justifies the cost with its accuracy and robust build. The accompanying app is user-friendly and provides detailed insights and historical data, enhancing the overall experience. Highly recommended for those seeking precise CO2 monitoring. I include what sensors are passed to Home Assistant for those interested.

It is indeed like it says. I've been working from home the past three years and I've noticed that when I've kept windows closed, I get tired after a while. If I remember to open the windows, then the air gets better and I get less tired. This could be hours of me being tired and trying to push through, not knowing for sure why I'm having difficulties in concentrating. Instead of remembering to open windows or even knowing when to open them, this device's screen turns from black on white to white on black when there is too much CO2 and it is immediately noticeable. This repeatedly, every day, saves me from getting too tired to remember anything. CO2 doesn't smell or taste anything, but it makes you tired and difficult to concentrate. This reminds me and tells me to get rid of it and helps me stay functioning. Only thing I wish was that I would have bought it sooner. I think it is a must buy for anyone habiting a closed / non-ventilated space.

It's actually improved my health. I used to get a lot of brain fog, when I started using this I realised the CO2 levels are dangerously high all the time. I keep windows ajar throughout the house and my brain fog and fatigue have been relieved.