I’ve had no fan problems on my Librem 13, but apparently other people have.
You might check these forum threads:
CPU fan stuck at high speed sometimes
Fan full blast after sleep, coreboot and Intel ME
Librem 13 v3 - Fan spin up at wake
Good luck. 
I’ve had no fan problems on my Librem 13, but apparently other people have.
You might check these forum threads:
CPU fan stuck at high speed sometimes
Fan full blast after sleep, coreboot and Intel ME
Librem 13 v3 - Fan spin up at wake
Good luck.