Sensirion hygrometer SHT4x test report
Sensirion Hygrometer SHT4x: I tested seven sensors for three weeks in seven closet humidors. References: Bodveda Butler, built-in humidor sensor and synthetic hair hygrometer. The Sensirion works via Bluetooth and is the company's latest model. It is said to display the RH accurately to +/- 1%. Read this article to find out how the comparison test turned out and whether this sensor is worth buying.
The set-up
Note: The Boveda sensors always showed the same values. After the test phase, I removed them all from the humidors to check them. The result: The app always shows the same values as in the humidors. The Boveda Butler is no longer available to buy. In the meantime, there have been several iOs updates without the app getting an update. Reading tip: Zigarren.Zone has reported on this.
I initially bought a Sensirion SHT4x sensor to test at zigarren-online.ch. After a few hours, I found the measurement results so interesting that I bought 6 more Sensirion SHT4x hygrometers. I decided to carry out a test.
The set-up:
- 7 Cabinet humidors
- In every cabinet humidor:
- 1 x Boveda Butler (I could have saved myself, see note above)
- 1 x synthetic hair hygrometer from the DIY store
- 1 x Sensirion SHT4x
- 1 x built-in sensor
- Test period: 20.11.21 - 11.12.21, between 09.00 am and 10.00 am
- The lounge was aired for 10 minutes between 07:00 and 08:00 on the days of the fair (balcony doors were open)
- The cupboards were opened from time to time during the day after measuring to take out or put in cigars. The door was open for about 30 seconds. They were not opened at all for days.
Super simple Sensirion hygrometer detection in the app
The app recognises the sensors very easily. It's a really great solution!
The Sensirion hygrometer measurement results
I was in the lounge for 15 control days during this time. You are welcome to download the PDF with the detailed measurements:
The Sensirion app
There is a QR code on the back of the sensor that will take you to the download of the app for iOs and Android. I have provided the direct links to the two operating systems at the bottom of the resources on the topic.
The app is simple and intuitive to use. You can pair multiple sensors. It works via Bluetooth. To quote „Big Bang Theory“: „Everything is better with Bluetooth.“
Conclusion
The Sensirion hygrometer is a great tool that I am happy to recommend. If you look at the PDF with the measurements, you can see how it constantly measures and displays humidity and temperature. It is amazingly cheap: only CHF 39.00. I have not seen this latest model from Sensirion in any other shop, status as of December 2021, except at zigarren-online.ch.
For the quick readers, just to be on the safe side Note: The Boveda sensors always showed the same values. After the test phase, I removed them all from the humidors to check them. The result: The app always shows the same values as in the humidors. The Boveda Butler is no longer available to buy. In the meantime, there have been several iOs updates without the app getting an update. Reading tip: Zigarren.Zone has reported on this.
The synthetic hair hygrometer shows changes from time to time, as does the internal sensor of the cabinet humidors.
In the PDF you will occasionally see „Ventilated to ...“. This means that I wanted a certain humidity value. If the humidity was too high, I left the door open a crack. That worked very well. Cuban cigars in particular like it when the humidity is around 69% (otherwise the draw resistance may be too strong). I have two cabinets with only Cuban cigars. In two cabinets, the proportion of Cuba is lower.
„Calibrated“ means: I set the internal hygrometers and the synthetic hair hygrometers to the value of the Sensirion. Worked reasonably well. I had to repeat the calibration several times.
Three areas are highlighted in colour in the app: Yellow / Green / Blue. I have not yet seen how I can colour my desired measuring range (68% - 72%) green. I assume that this is not possible. It's not necessary, it would be purely cosmetic.
Further down in the resources section you will find various links, including iOs and Android download of the app. Thank you for reading my test.
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Direct comparison. I have now packed 2 sht4.x and 2 sht3.x with a 72 Boveda in an l&l box. Let's wait 24 hours
Uh-oh. Boveda will swell up and implode ?? Good test, can't wait to see the result.
Test after 48h with 72 Boveda
Sensor 1 SHT3.X 74.54 %
Sensor 2 SHT3.X 74,37%
Sensor 3 SHT4.X 70,06%
Sensor 4 SHT4.X 69.99%
I will repeat the test under better conditions. I tested in the living room. The sensors were exposed to different temperatures there. I'll soon put everything in the cellar, where the temperatures should be more constant.
Tiptop. That says it all. The new ones are better ??☃️?❄️?
Correction: So far it says that the old ones have a drift;)
Great report. I have been using these sensors for a very long time and am very satisfied. I don't use the Bluetooth function so that the battery lasts longer. What I find a pity is that you can't calibrate this sensor and that you have a drift every year. I always calibrate it with bovedas and label it with the drift value. (... +4%)
Thank you very much. How long have you been using the SHT4x? As far as I know, this is a new model? But I could be wrong. https://www.sensirion.com/de/umweltsensoren/feuchtesensoren/smartgadget-sht4x/
Hello everyone, yes, the SHT4x has only recently come onto the market. Before that, the SHT3x was in use everywhere. ?
I use the SHT3.1 What is the difference to the new model?
Even more precise, even more economical in terms of power consumption. This will probably help you, then you can perhaps compare it with the old junk you are still using? ... fun ... ? Here: https://www.sensirion.com/de/umweltsensoren/feuchtesensoren/smartgadget-sht4x/
Thanks, then I'll probably convert... But you still can't calibrate them???
No. You don't have to.
Do they have no drift??? Only time will tell...
Unfortunately it doesn't say anything, stupid, I know. I'll copy an answer from INSTA that zigarren-online.ch gave to such a question: „It is no longer stated on the product itself for the 4x version. With the 31, however, it was 0.03% per year, so I don't think that could have any worse influence on the 4x. „
The drift actually takes place and is significantly higher than the 0.03 % on the one I now have an adhesive on it with -2.5% (approx. 1.5 years old)
Holy cow. That's a lot, of course.
Yes, quite a drift. But it's good that we've talked about it, I'll have to compare the ones from the L&L cans. Certainly also exciting
I have now ordered 2 of them.