Does this only happen when you have been running the A/C? Or after wet weather? If after wet weather, the AC upper unit has a gasket between the unit and the roof. The unit is tightened to the roof via four bolts from inside the RV. To access the bolts, the lower unit inside the coach needs to be removed. Best case scenario tighten bolts and the leak stops. If leak does not stop replace the gasket. For bolt torque specs Check online for the units installation manual. If it happens when running the unit it could be plugged drain holes. Pull upper units cover inspect and clean. There are some good youtube videos on how to proceed under RV AC maintenance / RV AC leak / RV AC gasket.
Dusty & Mikki
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