Caution - Keep an eye on Fantastic Vent Covers
A couple of years ago, I discovered our front vent cover completely open, the arm separated, and vent cracked as it was slammed back. I thought the storm the night before had caused the destruction. I could not remember if I had left the vent partially open or had closed it. I assumed the storm winds had "ripped" the vent cover up.
I now know that it was not the storm, but a malfunction in the raising/lowering system.
Last week on a trip I tried to raise the back vent but all that happened was the motor turning with no action. I tried to raise it manually but the handle only turned, so I figured something was worn and I would check it when we got back home. Today, dismantled the fan from inside and found that the raising handle was completely loose from the drive mechanism. It was worn, but now the vent cap could be raised by hand with nothing to keep it down. I was lucky that during the trip we didn't have rain with winds in a direction that would "pick up" the vent cover.
My suggestion is that we need to frequently make sure that the vents will open as they should. If they don't, then we need to make sure that the vent covers aren't loose. Because, if they are loose, a storm to blow open the vent and flood the trailer underneath it.