Rooftop A/C units remove moisture from indoor air. That water should drain to the roof and run off outside, not drip through the ceiling assembly.
Check for ice first
If the coil is frozen, water may drip inside as ice melts. Turn cooling off and run fan-only until thawed. Then correct filters, return-air blockage, closed vents or freeze-sensor problems. See RV AC freezes up.
Clear roof drain paths safely
Debris on the roof can block condensate channels. Use safe roof access only if your RV roof is rated for it. Avoid pressure washers and sharp tools near coils or plastic pans.
Check the air divider and roof gasket
If humid return air leaks into the cold supply side, condensation can form where it should not. A loose, over-compressed or under-compressed roof gasket can also let water enter during rain or A/C operation.
Tools, difficulty and likely cost
- Difficulty: Beginner for filters/thawing; intermediate/pro for roof access and gasket diagnosis.
- Useful tools: Towels, flashlight, soft brush, torque guidance from the A/C manual.
- Cost range: Filter/ice fixes are low-cost; gasket or pan repair depends on roof access and unit type.
Related RV Solver pages
- RV AC freezes up
- A/C airflow and icing guide
- A/C running but not cooling
- How to find an RV roof leak
- RV water damage warning signs
FAQ
Is dripping always a roof leak?
No. It may be condensation, ice melt or a blocked drain path rather than rainwater.
Can I tighten the A/C bolts?
Only to the manufacturer's specification. Overtightening can crush the gasket and make leaks worse.
Why does it drip only in humid weather?
High humidity increases condensate and makes airflow or plenum leaks more obvious.