You can move duct segments, duct fittings, and HVAC MvParts using Location grips, as shown next.
Example of a Location grip for a duct segment.
If the object is connected to a system, you can move connected objects in the current XY plane to maintain connectivity. The following illustrations show how location grips are used to move duct objects.
Top view of a duct run
Location grip used to move the duct branch to the adjacent room.
Duct branch moved to the new location
If a duct segment is not connected to another object, you can change its angle and length using the Start or End grip.
The Start and End grips change the XYZ location of the start point or endpoint of the segment. This makes them particularly useful when initially designing duct runs because you can use them to easily connect a segment to an existing run.