DHT22

Hi, I am trying to play with the DHT22 temperature and humidity sensor; I installed the DHT sensor library and tried to run the example "DHTtester".

It seems to work fine, but I have a doubt on how the sensor measures the temperature: if I put a hand in front of the sensor (touching-or almost touching it) the "heat index" rises quite rapidly to 36.something degrees (Celsius), while the "temperature" grows very slowly and after a long time still indicates 30.something degrees. Is it a malfunctioning of the sensor, or is it somewhat related to how the sensor measures the temperature (for example a kind of average from all the directions)?

Thanks in advance! :slight_smile:

What’s a “heat index” in this context? The sensor doesn’t provide such a value as far as I know.

The sensor measures the ambient air temperature. I’m surprised that it even reaches 30°C by just holding the hand in front of the sensor. If you touch the sensor it will need some time to heat the air inside it to the same temperature as your fingers have (which is probably considerably below 36 degrees as that’s the healthy body’s core temperature).