My laptop is a Dell Inspiron 15R 5520 and for a while I have noticed that when it is on AC power, its fans will temporarily run at max for several minutes before returning to normal operation, and then repeat this action at irregular intervals throughout the duration of the computer's battery charging time. Also, this only seems to happen when I begin to charge my battery when it is low. When I check for signs of overheating, my laptop's exhaust is blowing cool air, while cpu temperatures register in the upper 40s to low 50s (celsius).
Oddly, my fans will never overspeed like this when I am on battery power, and I tried using i8kutils to get the fans under control when the computer is on AC, but the program turned the fans off, completely. It would, however, turn the fans back on and run them at their max speed whenever I entered a command for i8k to automatically control their speed, but this only lasted a second before the fans shut off again, as if something was conflicting with i8k. I ended up uninstalling the program.
The only other times my fans will run at max for prolonged periods is when I am in my BIOS settings; when I sit at the GRUB menu for a while, or when I restart my computer rather than shutting it down completely.
I am using the latest BIOS.
Any ideas as to why my fans do this?