To View the iModel in 3D View

With the 3D View, you can view the plant model and choose objects to analyze.

Tip: You can select your default unit of measurement in User settings.

Zoom, Pan, and Walk through the model with on-screen or mouse controls or access saved spatial views of the model.

Follow these steps to view the iModel in 3D view.

In the Viewer, open the Views menu, and then choose 3D View.
The 3D View opens.
To open a view, do one of the following:

Click Spatial Views and select a spatial view from pop-up menu.

or
Use the Saved Views settings to create/load a saved view.

The selected view is applied in the 3D View.
Use , , and to rotate, pan, and zoom in/out respectively. Once your view is oriented and zoomed to your liking, you can filter the display to display only a certain category of objects then you can begin investigating them.
Click to expand the Categories menu. Choose HVAC from the menu.
The view is updated to only display HVAC objects.
Click to expand Measure Tools, then select Measure Distance, and then use the tools to investigate the displayed HVAC objects:
1. Using the mouse pointer, hover over a HVAC object.
  A flyover displays information about the object.
2. Click in the model to select the start point of the measurement.
3. Repeat steps to add more segments to the measurement.
  The total distance between selected measurement points appears in the view.