At roof top level remove the shroud covering your a c unit.
Rv roof ac drain off roof.
There are no drain lines for the ac unit on the roof of the rv.
Turn off the air conditioner unit.
The moisture that is removed from inside the rv must be relocated to the roof of the rv where it usually evaporates.
This moisture then drops down to the drip pan and is supposed to drain out the drain holes on both sides of the underside of the roof ac.
The condensation drips down into a pan which has an outlet on the side of the base pan that lets the water run onto the roof.
If it is leaking inside you most likely have a clogged outlet which can be easily opened with a stiff wire probed in the drain outlet.
I would suggest taking off the exterior shroud and metal evaporator shield and cleaning the drip pan and checking the drain holes.
The reason for this gap is that on most roof top a c units the condensation drains out the bottom of the unit between the base of the air conditioner and the roof.
On very hot and humid days well over 35 of the energy used by the roof air conditioner is for moisture removal alone.
The fix is easy.
Which ideally should drain the water from the evaporator coil on the roof instead of inside of the rv.
For safety sake put a lock out tag on the switch or thermostat to warn others not to turn it on or better still disconnect the power to the rv.
Typically a few screws or nuts hold it in place.