theyosh
commented
1 year ago This is a bit a known issue. They are not that stable.
There is a somewhat power management option where you can shutdown the sensor after readout. This requires an extra GPIO pin which is powering the DHT sensor: https://theyosh.github.io/TerrariumPI/hardware/#power-saving
But I am not sure if the sensor needs two seconds to get the first readout. Because the timeout after powering up is 1 second. So that could be to short.
So mostly I advise the BME280 sensor. It uses I2C and it for me pretty stable for now at least 5 years.
cjhudlin
Setup:
Describe the bug AM2303 / DHT22 sensor randomly drops out and is hard to get back
To Reproduce / Installation steps Random
Expected behavior work consistantly
Additional context Sometimes the AM2302 sensor drops out ramdomly. this is a common issue with these sensors, and i have replaced the sensor recently but still get the same issue. doing some reading, ive heard some mention that the sensor goes into a "halted" state when too many requests are being read from the sensor. maybe the sensor polling could be adjusted from its standard 2 seconds to maybe 2.5, with a 2.5 timeout instead of 0.5, or using a different library. usually the only way to fix this is to disconnet the sensor power for a minute or so, and it comes back, but this doesnt always work and the PI itself must be restarted, restarting docker isnt enough.
in the meantime, if there is another sensor that can output temp and humidity up to 100% that is cheaply available, ill probably use that instead!