Air conditioners are heavy. Removing the heavier chassis from its lightweight shell makes installation and maintenance much easier. All Chill models except the small-capacity, 5500 Btu CP05 feature a slide-out chassis.
Securely install the shell, then insert and affix the chassis according to directions. For a list of required tools as well as detailed instructions, please consult the Chill installation manual (PDF).
Yes, Chill can be installed in a window or thru-the-wall. Check the model specs to make sure your walls have the proper depth before you begin installation.