The Replace Family tool enables you to replace all instances of a device family in a project with a different device family. The alternative method is to right-click a symbol that uses the unwanted family, select Device ID, and specify a different family, then repeat for the remaining devices.
From the Tasks or ribbon area, select Review/Revise > *Replace > Replace Family
Select Search > Replace Symbol
* is used to denote a menu selection that is not necessary in some versions or platforms.