I recently purchased 3 Aqara Temperature and humidity sensors.
I put them into the fridge to test their accuracy. This is the result:
I think the result is pretty bad - you can clearly see that there is a temp difference of more than 1°C
That seems like a lot to me, or am I too eager? They were literaly lying right next to each other.
Anyone else with this problem?
There is an old saying which I wish I could remember where I first heard it.
“If you have one thermometer you know the temperature. If you have two or more you have confusion.” You need to spend really big money to buy thermometers that have very precise measurements and those need to be precisely calibrated.
Based on what Alex says, these seem to be performing within their published specifications, maybe just a tad worse.
If you do write a Rule, pay attention to what Jostein asked. Are they consistently off? For example, is Sensor3 always .5 lower than Sensor1 no matter where you are in the temperature range? Based on that graph I’m not so sure they are.
If being up to 1 degree off from each other is meaningful in your use case then you need to get more precise sensors or just pick one sensor. If not, just be sure you configure your hysteresis and remember when you look at the data that they have a range of uncertainty.