Passive refresh
I’ve bought and installed that Heat Dissipation for Raspberry.
Active refresh
I’ve installed a little fan, which is powered in continue by 3.3V of Raspberry.
To report out the temperature level inside the case, I’ve two LEDS (one green and one red), which are set on or off, controlled by a BASH script below, with GPIO Pins, as a function of measured temperature.
The surveillance of the temperature is run every minutes by Cron :
* * * * * bash /path/to/script/LED_Temp.sh > /dev/null
Fritzing of the wiring :