Hi @blsalvio its a bug, it’s depend of the type of your family instance and the detail level asked, but maybe you can build your duct fittings geometry with the workaround of @Kulkul and then get the face, or you can get the shape of duct fitting by Rhino inside…
Cheers
Revit/Dynamo Geometry - Duct fittings - 1/4 doughnut Revit vs 4/4 doughnut Dynamo (Torus)
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