Originally Posted by
plaster100665541
From the view above this happened when the ductwork is “other air”. From what I learned in Revit is “other air” is used to connect major systems like Return to Exhaust. It doesn’t work as a standalone system like trying to make it “outdoor air”. If you take the other air and change it to supply or return it will show in the section. We ran into this same problem not only horizontal but when we took the ductwork vertical in a shaft, on floor plans where this ductwork passed through would not show until we changed it to supply. I’m not saying this is your problem, just something to check.