I think there may have been some discussion on this topic before however I could not track it down. I am not sure what year Montana went to the "Quiet Cool System" but it was in the 2012's. It is certainly something the new 2013 owners should check and anyone else who might have this system and are experiencing poor AC operation.
The AC uses two return air ducts located in the living area which supply return air to the AC unit, having been advised of a possible problem I decided to check mine out and here is what I found after removing each vent cover.
The pictures were taken with my Iphone4 and show the blocked duct leading from each vent to the AC unit. One picture from each side.
There is no way the AC can get sufficient air to operate properly and explains why mine was not half what I thought it should have been last March in Arizona.
This is yet another example of absolutely crappy workmanship and materials used in the construction of the Montana. I feel lucky to have discovered this prior to the end of my warranty period, but if I had not I would raise such a stink over this it would be heard all the way to Indiana. Yet another thing to be fixed before I can go away and enjoy my very expensive Montana.
I encourage all who have not checked their vents to do so, you may be surprised at what you find.
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