I am trying to run a CFD analysis on a HVAC model I made for a residential house to see if the air pressure and speed will adequately reach the ends of the HVAC layout. I have the converted my file to a step file so I can select faces as inlets and outlets but now it is saying under geometry that I have sheet bodies left and there are zero solid bodies. I tried to convert my step into a solid form and thought I did but am encountering the same problem. Can anyone help me? My title is HVAC Trial 3.