1.In the Floor Plan or 3D window, use any construction elements (e.g. Wall, Slab, Object, MEP element) to model a custom MEP part.
2.If your custom MEP element requires one or more connections, you must use the MEP Connection object as part of your element. This is available from the MEP Library:
3.From the 3D window: Use File > Libraries and Objects > Save Selection As > MEP Part
4.Enter a File Name and destination for the object.
5.Choose a subtype from the Type drop-down list:
Note: The available subtypes depend on the number and type of MEP Connection objects contained in the custom object. If it has only a single connection, the equipment and in-line subtypes (which require multiple collinear connections) are not available here.
6.Click Save. The new MEP object is accessible from the tool settings of the chosen subtype.