I found the same thing with the AC unit in my 2016 Axis and used duct tape to secure that buffer piece and make sure it did not bleed air. Installing the four inch circular vent in the shroud of the Coleman (as Shown in previous threads) makes an incredible difference in air flow to the living area - as you would imagine based on davepetroski's observations. The small vents seem like a good idea to direct air cooling flow to different areas in the RV, but they block a lot of air from ever getting into the RV and the channels are right up next to the roof where they are heated by the sun.
__________________
|