I just purchased a 2014 impact travel trailer. It has a 15000btu ac. The toy hauler and the bedroom have minimal air coming out of the vents even when they are all the way open and the vents on main...
My TT has ducts that can be directed and a straight downflow that can be open or closed. Is it possible that your ducts in the main area are closed but the straight down flow is open meaning very little cool air is getting to the far rooms?