Dash AC

Does the end of the disconnected line have part of a broken off connector in it? Do you see any plastic jugs under the dash with a small nipple that would fit the disconnected hose? You could maybe try starting the MH and see if you can hear a vacuum leak under the dash.

Reno55 wrote:
We have a 1999 Winne 37' coach. The engine is a Ford V-10. My situation is when we run the AC, it blows through the defrost vents at the windshield. I have selected the different positions on the switch and no changes. I have checked the vaccum lines and they are all connected except one. The one apparently provides the vaccum from the engine runs from the control to under the dash towards the engine. I have looked for qute some time and unable to locate it. Any comments and suggestions are greatly appreciated.

I had the same problem with mine. Tried so many things. So many technicians looked at it, never could correct it. Then I received some advice from a gentleman on this forum named Doug. He suggested the fix to be a separate 12 volt vacuum pump (like they have on diesel engines) be added. I was skeptical, but bought the pump (wasn't expensive) connected to a 12 volt source, and a dashboard switch. Turned the switch on when using the a/c. Vents worked perfectly from that point forward. Never had another problem with it.

The damper "doors" are vacuum operated.
That loose hose likely IS your problem.
If you can't find where it goes, you need help from someone who knows.
Make some phone calls.....to RV dealers or Ford truck shops.