As I am getting strange readings. At a certain time at night humidty drops to 0% but temperature also is falling. But them it goes from 0% to 100% when the temperature is rising?
I think I have sorted it out, so I thought I would share.
I put the sensor si7021 into a plastic housing (sonoff smart box). I removed one of the cable glands to allow for ‘humidty’ to enter, and also for temperature to penetrate through the plastic quicker.
The next thing I am going to do. Is to coil up the short sensor cable into the box, so the sensor plug is more secure and drier inside. The box was then screwed to the greenhouse framework, in the shade of the sun.
The 2 temperature / humidty graphs, show readings for the outside and also just inside the greenhouse. This shows the 2 lines roughly follow each other.