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1.27 mi | ASHBURN 20147

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Returns
Eligible for Return, Refund or Replacement within 30 days of receipt
Returnable Yes
Resolutions Eligible for refund or replacement
Return Window 30 days from delivery
Refund Timelines Typically, an advance refund will be issued within 24 hours of a drop-off or pick-up. For returns that require physical verification, refund issuance may take up to 30 days after drop-off or pick up. Where an advance refund is issued, we will re-charge your payment method if we do not receive the correct item in original condition. See details here.
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SAF Aranet4 Home: Wireless Indoor Air Quality Monitor for Office or School (CO2, Temperature, Humidity and More) Portable, Battery Powered, E-Ink Screen, App for Configuration & Data History

$168.00
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Purchase options and add-ons

Color White
Brand SAF
Product Dimensions 2.76"W x 2.76"H
Item Weight 104 Grams
Battery Description Alkaline

About this item

  • BREATHE EASILY: Aranet4 CO2 meter measures CO2 levels, temperature, relative humidity, and atmospheric pressure in real-time, empowering you to make informed decisions for healthy ventilation. No wonder it's the top-rated indoor air quality monitor in Amazon's CO2 monitor segment!
  • CABLE-FREE: The power-efficient e-ink display guarantees an extended battery life of up to 4 years for this wireless air quality monitor, ensuring worry-free monitoring without the hassle of cables and cords.
  • EASY-TO-USE: The color coding, prominent CO2 number on the display, and optional buzzer of this air quality meter alert you when the CO2 concentration becomes too high.
  • FREE & INTERACTIVE APP: A smartphone application for viewing and analyzing up to 90 days of historical data from your indoor air quality meter, complete with user-friendly graphs.
  • PREMIUM QUALITY: Aranet4 carbon dioxide detectors use nondispersive infrared sensor (NDIR) technology for the most precise and reliable CO2 measurements. Made in the European Union.
  • ENJOY THE HEALTH BENEFITS: Air quality monitor indoor use helps people take better care of the atmosphere around them, leading to improved focus, mood, and overall well-being.

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Product details

  • Language ‏ : ‎ Spanish, English
  • Product Dimensions ‏ : ‎ 0.94 x 2.76 x 2.76 inches; 3.67 ounces
  • Item model number ‏ : ‎ TDSPC003.001
  • Batteries ‏ : ‎ 2 AA batteries required. (included)
  • Date First Available ‏ : ‎ July 18, 2019
  • Manufacturer ‏ : ‎ SAF Tehnika
  • ASIN ‏ : ‎ B07YY7BH2W
  • Customer Reviews:

Product Description

Improve your well-being!

What we breathe makes a big difference in how we feel. This is why air quality monitors have become so amazingly popular. The Aranet4 is a specialized sensor providing a wealth of health-centric data to you so you can make informed decisions about ventilation and where to spend your time.

Take care of your air!

CO2, CO2 monitor, carbon dioxide

Carbon Dioxide

This odorless gas is harmless in small quantities. However, increased concentrations negatively impact productivity, health, and indoor air quality.

Humidity

Temperature

Humans operate best under specific conditions. Studies show that maintaining a range of 68-76 °F (21-22 °C) is ideal within homes, offices, etc.

Temperature

Relative Humidity

Finding the correct balance of moisture (30-60%) in an indoor environment is key to ensuring human comfort.

Pressure

Atmospheric Pressure

Atmospheric pressure affects human well-being, impacting breathing, blood pressure, and ear pressure, especially during altitude changes.

Air quality, ari quality monitor, air quality monitoring, co2, co2 monitoring

Free app

  • It allows you to see the measurement history going back 90 days or see CO2 measurement in real-time.
  • Allows you to see the readings you had during the night or while you were away from home.
  • Makes it easy to track progress, when implementing changes in your home ventilation, so you can find the best solutions for your home and make smarter decisions.
  • Makes it easy to change various settings for your Aranet device.
  • You can turn on the buzzer and change the warning thresholds to custom settings.

Why do I need monitor CO2 concentration?

High CO2 levels can negatively affect your well-being, comfort, and productivity. For example, if CO2 levels reach 1000 ppm, your cognitive abilities drop by 15%. At 1400 ppm and above, they decrease by a staggering 50%.

What is the NDIR sensor and why is it preferred over other types of sensors?

Because it provides a higher precision than regular electrochemical sensors because CO2 is uniquely detectable with no interference from other gasses. Besides that the lifespan of the NDIR sensor is much longer and less recalibration is needed.

Why is Aranet4 considered the gold standard in CO2 monitoring?

Aranet4 excels with multi-sensor accuracy, real-time alerts, app connectivity, and user-friendly design, highly praised by numerous satisfied customers.

Wireless and portable – take your Aranet4 wherever you go!

Indoor air quality

Aranet4 HOME is easy and fun to use. You can move it between rooms in your house, take it to hotels during business trips, or monitor the air quality in classrooms, conference rooms, museums, parties, concerts, and so many other places. Bring Aranet4 HOME with you wherever you go!

Looking for specific info?

Customer reviews

4.7 out of 5 stars
4.7 out of 5
1,301 global ratings

Customers say

Customers like the portability, accuracy, readability, and quality of the humidity meter. For example, they mention it's very compact, easy to read, and well made. That said, some disagree on value.

AI-generated from the text of customer reviews

Select to learn more
AccuracyAlignmentEase of useAir qualityQualityPortabilityReadabilityValue
99 customers mention "Accuracy"71 positive28 negative

Customers like the accuracy of the humidity meter. They mention the app works well, they have no issues with the device, and it's overall very good. The iPhone app works great with Home Assistant, and the sensor connects to Bluetooth easily. Overall, customers say it'd be a very useful tool for health.

"The aranet4 is such an excellent monitor, and really is the best bang for your buck in an accurate and easy to use monitor...." Read more

"...The app is simple and does the job...." Read more

"...It also works great with Home Assistant, which has made it really nice to correlate CO2 levels in concert with other smart devices and sensors to..." Read more

"...Fresh air is HIGH in CO2 ??? It actually said it is double what my original meter reads. Very disappointing, waste of money.""..." Read more

54 customers mention "Alignment"51 positive3 negative

Customers are satisfied with the alignment of the humidity meter. They mention that it is very precise with the CO2 measurements, and the calibration seems to be good. The measurements are consistently accurate, and it is nice to correlate CO2 levels in concert with other smart devices. It is also incredibly handy to check the CO 2ppm on flights.

"This thing is synonymous with accuracy. It's pricey. But definitely well made. Solid...." Read more

"...an excellent monitor, and really is the best bang for your buck in an accurate and easy to use monitor...." Read more

"...also works great with Home Assistant, which has made it really nice to correlate CO2 levels in concert with other smart devices and sensors to get a..." Read more

"...After calibration, it measures very accurately, and I'm happy with my purchase all around. However, I'd say calibration is mandatory...." Read more

54 customers mention "Ease of use"54 positive0 negative

Customers find the humidity meter easy to use. They say it's intuitive, simple, and works as expected. Customers also say the app has a great user interface and it'll extend the device's usability. They mention it'd be easy to set up and monitor CO2 levels in their home.

"...this monitor in the main living area of our house and it's every easy to monitor when the C02 is accumulating and we need to crack a window or turn..." Read more

"...The color coding on the device makes it super easy to understand when the air quality is getting bad, and the buzzer is a neat feature too, although..." Read more

"...It is easy to use. If you download their app to your phone, you can easily download the data it collects...." Read more

"...What I Love:--It's incredibly easy to set up, and easy to use.--The battery life has been great...." Read more

51 customers mention "Air quality"46 positive5 negative

Customers find the humidity meter very useful to know the indoor air quality and to see how different things change it. They say it helps maintain productivity by ensuring good air quality. They also say it keeps a record of the air quality data and that it's reassuring to test air quality when family member was in the hospital. Overall, customers say the humidity monitor is a helpful analytical tool that helps them live a better life and get more fresh air.

"...The app is simple and does the job. It keeps a record of the air quality data, so I’ve started geeking out on comparing the air quality in different..." Read more

"...It's just an incredible sensor to have -- you can pocket it or bring it somewhere in a backpack and still have CO2 measurements, where most sensors..." Read more

"...Overall, it is a handy little device and I recommend it if you need it for it's designed purpose...." Read more

"...astonishing to see how bad (or occasionally good) the air quality is in certain spaces...." Read more

44 customers mention "Quality"32 positive12 negative

Customers generally like the quality of the humidity meter. They say it's well-made, reliable, and durable. They also say it makes them aware of the quality and durability of their surrounding air quality. Customers also mention that the craftsmanship is top notch, and it has survived a plane trip and constant use. Overall, customers find the product to be impressive, highly portable, and easy to read.

"...It's pricey. But definitely well made. Solid. The e-paper display is crystal clear, and ensures the battery lasts a VERY long time...." Read more

"...Totally worth the money and a reliable, trustworthy device for monitoring a really important aspect of our health." Read more

"...It seems pretty durable build-quality wise and easy to take on the go without worrying about it getting banged up...." Read more

"...packaging clearly retaped, amazon return barcode on packaging, manual ripped, and tool missing...." Read more

43 customers mention "Portability"43 positive0 negative

Customers like the portability of the humidity meter. They mention it's very compact, light, and useful in these troubled times. They also say it has excellent accuracy and is easy to take on the go.

"...Not TINY, but portable enough to take around and check various areas for CO2 levels. The biggest offender for me so far? My car with the AC on recirc." Read more

"...easy to set up, the battery life is excellent, and it's easy to bring with you anywhere. The app works well and is likewise a quick and easy setup...." Read more

"...I love that the Aranet4 is portable. I've taken it with me on trips, and it's kind of become my travel buddy...." Read more

"...It seems pretty durable build-quality wise and easy to take on the go without worrying about it getting banged up...." Read more

39 customers mention "Readability"29 positive10 negative

Customers find the humidity meter easy to read. They say the numbers are clear and legible from across the room. The e-paper display is incredibly clear and impressive. Customers also appreciate the attention to detail, from the hardware to the app. They enjoy using it and being able to see the readings in different environments.

"...It's pricey. But definitely well made. Solid. The e-paper display is crystal clear, and ensures the battery lasts a VERY long time...." Read more

"...So yeah, I’m really glad I got the Aranet4. It’s helped me understand my spaces better and take simple steps to improve the air quality around me...." Read more

"...The iOS app itself is perfunctory. It provides graphing, exporting data (as csv, including CO2, pressure, humidity, temperature, and date of sample)..." Read more

"...Unfortunately, this meter reads double what my other meter reads...." Read more

56 customers mention "Value"31 positive25 negative

Customers are mixed about the value of the humidity meter. Some mention it's worth the money, has a great app, and is fast to set up. However, some say it'd be better off with a different meter and a less useful app.

"The aranet4 is such an excellent monitor, and really is the best bang for your buck in an accurate and easy to use monitor...." Read more

"This thing is synonymous with accuracy. It's pricey. But definitely well made. Solid...." Read more

"...On the app side, Aranet4 provides a serviceable iOS app. The iOS app itself is perfunctory...." Read more

"...You’re paying for quality and accuracy." Read more

Great device, compact with nice app
5 Stars
Great device, compact with nice app
Initially bought to evaluate if we wanted to switch our range from gas to induction. But then started measuring home office (surprisingly bad), kids room, flights (yikes!), etc.The refresh rate is maddeningly slow, but I guess that’s the price we pay for long battery life.It’s a winner. Wish it measured CO too.
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Top reviews from the United States

Neil Fusillo
5.0 out of 5 stars Nice little device with a lot of battery life.
Reviewed in the United States on June 29, 2024
Verified Purchase
This thing is synonymous with accuracy. It's pricey. But definitely well made. Solid. The e-paper display is crystal clear, and ensures the battery lasts a VERY long time. Not TINY, but portable enough to take around and check various areas for CO2 levels. The biggest offender for me so far? My car with the AC on recirc.
3 people found this helpful
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Raphael Wiggomo
5.0 out of 5 stars Excellent C02 Monitor
Reviewed in the United States on December 30, 2023
Verified Purchase
The aranet4 is such an excellent monitor, and really is the best bang for your buck in an accurate and easy to use monitor. We have used this in all the rooms of our home to measure air flow and how quickly C02 builds up - especially useful in the kitchen during various cooking processes and in the bedrooms overnight - but we have also brought it to work to measure the C02 and get an idea of the air flow in various offices as well. It's easy to set up, the battery life is excellent, and it's easy to bring with you anywhere. The app works well and is likewise a quick and easy setup. We keep this monitor in the main living area of our house and it's every easy to monitor when the C02 is accumulating and we need to crack a window or turn on an exhaust fan. It's been illuminating. This item is also very accurate, and more so than others and cheaper version. Totally worth the money and a reliable, trustworthy device for monitoring a really important aspect of our health.
18 people found this helpful
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nicholas
5.0 out of 5 stars A Breath of Fresh Insight: Monitoring Air Quality Effortlessly
Reviewed in the United States on October 29, 2023
Verified Purchase
I got the SAF Aranet4 Home mainly because I was curious about why I'd get so groggy in one particular room of my house. This little gadget was easy to set up right out of the box and it immediately started giving me the lowdown on my air quality. Turns out, the CO2 levels in that room were off the charts sometimes - no wonder I felt like I was in a brain fog half the time.

I love that the Aranet4 is portable. I've taken it with me on trips, and it's kind of become my travel buddy. It’s wild to see the CO2 levels on airplanes and in hotel rooms. The color coding on the device makes it super easy to understand when the air quality is getting bad, and the buzzer is a neat feature too, although I turned it off after a while because it startled my cat.

The app is simple and does the job. It keeps a record of the air quality data, so I’ve started geeking out on comparing the air quality in different places I go. The e-ink display is clear, and the battery just keeps going - haven’t had to charge it yet!

The Aranet4 is not just a fancy gadget; it’s been a real eye-opener for me. It made me realize how the air quality around us can affect how we feel. Now, instead of guessing, I know when to crack open a window to get some fresh air in. It’s pretty satisfying to see the CO2 levels drop and feel that mental clarity kick in. Honestly, in these COVID times, it’s comforting to have a better grasp on the air I’m breathing, especially in new or unfamiliar places.

So yeah, I’m really glad I got the Aranet4. It’s helped me understand my spaces better and take simple steps to improve the air quality around me. Plus, it’s kind of fun having this little gadget with me, measuring the unseen world of air quality wherever I go.

Update: have lent the device to several friends now to test their apartments, and they've all found ways to improve their air quality!
56 people found this helpful
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dome
5.0 out of 5 stars Unknown accuracy but at least consistent
Reviewed in the United States on January 30, 2024
Verified Purchase
The refresh rate on the screen is a few minutes, but this has been fine for my uses. I've taken this little guy on public transit, hotels, and various other places--it's easy to just throw in my bag and take it with me. It seems pretty durable build-quality wise and easy to take on the go without worrying about it getting banged up.

I'm not sure how accurate it is since I don't have any other instruments to measure CO2, but it's at least consistent and I can see the numbers rise in situations I would expect it to.

It also works great with Home Assistant, which has made it really nice to correlate CO2 levels in concert with other smart devices and sensors to get a better picture/correlation to what helps/hurts CO2 levels in a room.
3 people found this helpful
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Lucas Nicodemus
5.0 out of 5 stars After manual calibration, this is a very awesome battery-powered CO2 sensor
Reviewed in the United States on April 14, 2022
Verified Purchase
I've owned several CO2 sensors. In particular, I've had 2 Awair Glow units, 1 first-generation Awair unit, 1 second-generation Awair unit, and a TIM10 CO2 sensor. Of these sensors, the TIM10 is my "gold standard" sensor, but it has the very, very annoying property of requiring AC power. Aranet4 promised to be a battery-powered CO2 sensor that could output data to an app. It delivers, but it requires calibration out-of-the-box, in my opinion.

Measured against known good sensors (particularly my TIM10), my Aranet4 sensor read about 75ppm higher than the environmental level out-of-the-box. The app warns you that performing calibration will permanently erase the factory calibration data, which is somewhat scary, but I did it anyway. In order to validate that the calibration was successful, I had my trusted TIM10 sensor outdoors, connected to AC power, out of the sun, with the Aranet4 directly next to it, on a substantially windy day with extremely good air quality (as measured by PM2.5 and PM10 presence from AirNow and Purple Air). The floor, outdoors, in this configuration, as read by the TIM10 unit, was 380ppm of CO2. Before calibration, in the same environment, Aranet4 reported 480ppm. After calibration, Aranet4 reported within 15ppm of TIM10, which I considered a success, particularly given the rarity of having such a low reading. All of the Awair units bottom out at 400ppm.

Following calibration, for the last few weeks, I've kept an eye on Aranet4 and TIM10 when they've been in the same room. There's approximately a 10-15ppm disagreement between TIM10 and Aranet4, which I consider a very acceptable deviation given that Aranet4 is battery powered, and TIM10 is AC powered.

On the app side, Aranet4 provides a serviceable iOS app. The iOS app itself is perfunctory. It provides graphing, exporting data (as csv, including CO2, pressure, humidity, temperature, and date of sample), and basic reporting features. It doesn't support dark mode, though, as an example of its perfunctory nature. The app developers didn't consider the performance impacts that storing all of the data would have on the graphing component, though, so the app gets laggier the more data the sensor measures. You're also only going to get a week of data for historical measurement.

Other details are worth mentioning beyond the sensor accuracy and app integration, though. E-ink, as a display type, is just awesome. It looks very nice, aesthetically. Each refresh blanks the screen temporarily, though. Keep this in mind, if you decrease the measurement interval (you can measure as frequently as once per minute). Also, there's no backlight, which is why the battery life is good, but keep this in mind too, if you want to see it in the dark.

I've taken this sensor on an airplane, and it works great there too. It's just an incredible sensor to have -- you can pocket it or bring it somewhere in a backpack and still have CO2 measurements, where most sensors can't go. For travel, or just in general, it's a great device to have. After calibration, it measures very accurately, and I'm happy with my purchase all around. However, I'd say calibration is mandatory.

I've included a screenshot of a graph made from the CSV, as well as the CSV data from the unit itself.
Customer image
Lucas Nicodemus
5.0 out of 5 stars After manual calibration, this is a very awesome battery-powered CO2 sensor
Reviewed in the United States on April 14, 2022
I've owned several CO2 sensors. In particular, I've had 2 Awair Glow units, 1 first-generation Awair unit, 1 second-generation Awair unit, and a TIM10 CO2 sensor. Of these sensors, the TIM10 is my "gold standard" sensor, but it has the very, very annoying property of requiring AC power. Aranet4 promised to be a battery-powered CO2 sensor that could output data to an app. It delivers, but it requires calibration out-of-the-box, in my opinion.

Measured against known good sensors (particularly my TIM10), my Aranet4 sensor read about 75ppm higher than the environmental level out-of-the-box. The app warns you that performing calibration will permanently erase the factory calibration data, which is somewhat scary, but I did it anyway. In order to validate that the calibration was successful, I had my trusted TIM10 sensor outdoors, connected to AC power, out of the sun, with the Aranet4 directly next to it, on a substantially windy day with extremely good air quality (as measured by PM2.5 and PM10 presence from AirNow and Purple Air). The floor, outdoors, in this configuration, as read by the TIM10 unit, was 380ppm of CO2. Before calibration, in the same environment, Aranet4 reported 480ppm. After calibration, Aranet4 reported within 15ppm of TIM10, which I considered a success, particularly given the rarity of having such a low reading. All of the Awair units bottom out at 400ppm.

Following calibration, for the last few weeks, I've kept an eye on Aranet4 and TIM10 when they've been in the same room. There's approximately a 10-15ppm disagreement between TIM10 and Aranet4, which I consider a very acceptable deviation given that Aranet4 is battery powered, and TIM10 is AC powered.

On the app side, Aranet4 provides a serviceable iOS app. The iOS app itself is perfunctory. It provides graphing, exporting data (as csv, including CO2, pressure, humidity, temperature, and date of sample), and basic reporting features. It doesn't support dark mode, though, as an example of its perfunctory nature. The app developers didn't consider the performance impacts that storing all of the data would have on the graphing component, though, so the app gets laggier the more data the sensor measures. You're also only going to get a week of data for historical measurement.

Other details are worth mentioning beyond the sensor accuracy and app integration, though. E-ink, as a display type, is just awesome. It looks very nice, aesthetically. Each refresh blanks the screen temporarily, though. Keep this in mind, if you decrease the measurement interval (you can measure as frequently as once per minute). Also, there's no backlight, which is why the battery life is good, but keep this in mind too, if you want to see it in the dark.

I've taken this sensor on an airplane, and it works great there too. It's just an incredible sensor to have -- you can pocket it or bring it somewhere in a backpack and still have CO2 measurements, where most sensors can't go. For travel, or just in general, it's a great device to have. After calibration, it measures very accurately, and I'm happy with my purchase all around. However, I'd say calibration is mandatory.

I've included a screenshot of a graph made from the CSV, as well as the CSV data from the unit itself.
Images in this review
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140 people found this helpful
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Top reviews from other countries

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Meep
5.0 out of 5 stars Extremely valuable data from a compact device!
Reviewed in Canada on April 30, 2024
Verified Purchase
I love my Aranet4 so much! I love being able to see exactly how much CO² is in a given space and adjust accordingly.

Monitoring my CO² has helped me reduce headaches at home, and helps me determine if a public space has good air circulation or not.

I payed with Afterpay so I could afford my Aranet4. I also used the Karma app to monitor the cost and purchased it when there was a flash sale.
Customer image
Meep
5.0 out of 5 stars Extremely valuable data from a compact device!
Reviewed in Canada on April 30, 2024
I love my Aranet4 so much! I love being able to see exactly how much CO² is in a given space and adjust accordingly.

Monitoring my CO² has helped me reduce headaches at home, and helps me determine if a public space has good air circulation or not.

I payed with Afterpay so I could afford my Aranet4. I also used the Karma app to monitor the cost and purchased it when there was a flash sale.
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Customer image
2 people found this helpful
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AAJiménez
5.0 out of 5 stars Precisó y útil.
Reviewed in Mexico on July 20, 2022
Verified Purchase
Es fácil de usar y muy preciso.
One person found this helpful
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Fredera
5.0 out of 5 stars Very good quality of sensor and connection to HA
Reviewed in Belgium on June 7, 2024
Verified Purchase
Although this sensor is not the cheapest one it is so easy to setup, you can use the designated app but it also immediately connects to Home Assistant Smart home.
Very stable connection, CO2 reading seems to be very correct, it has battery which last a long time.

Worth it's money.
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brabs
4.0 out of 5 stars Great for getting reference data on CO2 + T&H. HOWEVER, Delivery via Chronopost was awful
Reviewed in France on May 7, 2024
Verified Purchase
Really happy with the product itself
GOOD: It is quite expensive but, at least, you are getting professional quality sensors for CO2, Temperature and Humidity.

BAD: This was apparently imported from the UK (awkward as the company is in EU...) and the delivery in France via Chronopost was awful: this EUR 200+ device was just dropped into the common mailbox for the building for any resident to pick up! no phone call / no ring on the door bell. Got lucky that I had a friend in the building picking it up for me...
A unpleasing experience quite rare with Amazon who usually are spotless in their selection of delivery partner.
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Pusemuckel
5.0 out of 5 stars Handlicher CO2 Sensor mit sehr guter App
Reviewed in Germany on February 11, 2024
Verified Purchase
Der CO2 Sensor ist gut und sicher verpackt. Macht einen wertigen Eindruck und sieht gut aus.
Dank der Verwendung normaler Batterien und seiner geringen Größe kann man ihn einfach mal in ein anderes Zimmer stellen oder mitnehmen. Viele andere vergleichbare Geräte haben einen kurzzeitigen Akkubetrieb oder erfordern einen Netzanschluss.

Die Bluetooth-Verbindung mit der zugehörigen App ging schnell und einfach. Die Verbindung ist stabil. Kein Re-Connect erforderlich wenn man zB außer Reichweite war.

Die Anzeige am Gerät ist gut ablesbar. Meist schaue ich aber über die App, da hier auch der zeitliche Verlauf angezeigt wird.
In der c‘t 27/2023 war ein Bericht über CO2 Messgeräte und der Aranet4 hat mich trotz des hohen Preises mein Interesse gefunden. Das hat sich im Betrieb bestätigt.

Mit dem Gerät und der App bin ich sehr zufrieden.

Was negativ zu erwähnen ist, ist die starke Preiserhöhung um €30 wohl zum Februar 2024. Ende Januar hab ich noch €179 bezahlt, aktuell kostet er €209.

Versand kommt schnell aus Lettland (EU) mit €10 VK.
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