just looked at FR's specs for the 2306 and a YouTube tour of one and it doesn't have ducted a/c.
it has what's often called "BFC or Blast From the Center" a/c.
i saw no evidence, in the video, of any a/c duct vents on the ceiling.
ducted a/c usually has a flat/flush grill where the a/c is and numerous round ducts that have louvers and can be directed by rotating them.
you could post pics of what you're referring to as ceiling openings, to figure out what they are.
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