Ventilation collection:
https://3dsky.org/collection/shared/5333943 

CORONA + VRAY (2013)
FBX CORONA + VRAY (2009)

Ventilation system for ceilings.
The set includes an assembled ceiling made up of several ready-made modules and a set of individual elements for assembling various options.
The model features 3 types of exhausts, a duct system, air conditioners, and a fire protection system.
The set uses 6 types of materials that can be applied to any element.
The dimensions of the rectangular ducts are 200 x 150, 300 x 200, 400 x 300 mm.
The diameters of the round ducts are 200, 315 mm.
The main parts of the details can be edited using Edit Poly and adjusted to the required sizes.

Other sets:
https://3dsky.org/users/solomon5555/models