It wouldn’t be a drain issue. It sounds like cold air is blowing onto the ceiling. The ac is mounted on the roof and the cold air exits out the bottom into a circular ducted raceway. This raceway runs all the way to the front bedroom and picks up bedroom ac air and returns on the opposite side of the RV to the rear ac. Like a race track.
It sounds like you have cold air not being contained in the raceway where the air enters the RV.
Have you had this issue before? Did you leave a door or window open? When it is real humid and you leave a door or window open I have seen water build up on the output registers. Where are you camping?
You say it’s a new unit. Have the dealer look at it.
It does not sound like a water leak. Feel,the ceiling where you see this and see if it is cold.
2016 Siverback 33IK, Towed 40K+ miles
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