How to powerwash
You can powerwash if you do Ctrl + Alt + Shift + R
on
the sign-in page. The Chromebook will ask you to reboot, and then once it
reboots the dialog for powerwashing will come up.
It is not recommended to powerwash a device that is running a test image, as this will remove rsync and other tools needed for deploying.
Note: Powerwashing is not available on managed devices.