Cleaning a camper AC unit means cutting all power, removing the filter and rooftop shroud, then cleaning the coils and drain path.
A dirty rooftop air conditioner doesn’t just blow weak air — it works harder, cools slower, and can drip condensation inside your rig. The good news: a thorough cleaning takes about an hour with basic hand tools. The process comes down to cutting power, removing the filter and shroud, cleaning the coils, and clearing the drain path. Do that on a regular schedule, and your unit will run quieter and cooler all season.
Below is the full sequence, followed by what to use, what not to do, and how often to bother with it.
Before You Start: Shut Everything Down
Cut power completely before touching anything. RV guidance consistently says to disconnect shore power and turn off the breaker for the AC unit; for extra safety, some procedures also disconnect the DC battery and generator power.
You’ll need:
- Phillips screwdriver for shroud screws.
- Soft-bristle brush or coil brush for debris.
- Fin comb for bent aluminum fins.
- Foaming AC coil cleaner.
- Vacuum with brush attachment, shop rags, and towels.
Working with power connected risks electric shock and can damage the unit’s control board. Skip the temptation to “just loosen one screw” while it’s live.
Remove the Filter and Rooftop Shroud
Inside the camper, pull the return-air filter from the ceiling assembly. Washable foam filters can be cleaned with mild soap and water, then dried completely. Disposable pleated paper filters should be replaced rather than washed. Lippert advises soaking a filter for no more than 30 minutes if it’s heavily soiled.
Head up top and remove the shroud screws with a Phillips driver. Set the shroud aside on a towel — the plastic is brittle, and over-tightening those screws on reassembly is a common way to crack it. If your unit has a foam evaporator cover over the indoor coil, remove that too.
One pro tip worth stealing: photograph the freeze sensor before removing anything so you can return it to the same position later.
Clean the Coils, Fins, and Drain Path
With the shroud off, you’ll see the condenser coil (outdoor side) and, once the evaporator cover is removed, the indoor coil. Keystone RV’s official procedure: check for large debris, lay a towel inside the unit, straighten bent fins with a fin comb, then use compressed air or a vacuum to remove dust.
For deeper cleaning, use a foaming coil cleaner on the fins, let it sit per the label, then wipe with a damp cloth and shop rags. Lippert’s guidance is to use cold water with mild detergent for visible grime, and a one-to-one vinegar-water solution if you spot mold or mildew.
Two hard rules here:
- Never use a pressure washer. The aluminum fins bend easily and the water forces moisture into electrical components.
- Keep water away from the fan motor and wiring. Rinse gently and aim so water drains from the unit, not toward sensitive parts.
Finally, clear the drain pan and drain holes so condensate flows freely. A blocked drain is a leading cause of water dripping inside the camper, yet it’s the step most people skip. Camping World’s RV maintenance guide calls drain cleaning out as part of a complete service.
Reassemble, Restore Power, and Test
Let everything dry completely — coils, drain pan, and filter. Reinstalling a damp filter risks mold and restricted airflow. Reattach the evaporator cover, then the shroud, tightening screws snug but not hard. Restore power and run the unit for 10–15 minutes, checking for normal airflow, cooling, and any unusual rattles or vibrations.
A quiet, strong airflow confirms the cleaning worked. If airflow still seems weak, repeat the coil cleaning or inspect the fins for bends you may have missed.
| Part | Cleaning Method | Frequency |
|---|---|---|
| Air filter (washable) | Wash with mild soap, dry fully | Monthly for full-timers |
| Air filter (disposable) | Replace, never wash | Every 2–3 months |
| Coils and fins | Vacuum, coil cleaner, fin comb | When airflow drops or dirt is visible |
| Drain pan and holes | Clear debris, flush gently | Each coil cleaning |
| Shroud and gasket | Wipe with damp cloth | Each coil cleaning |
For full-time RVers, Camping World recommends inspecting and cleaning the filter at least once a month. Coil cleaning happens less often — whenever airflow drops, you see visible dirt, or the unit gets noisy. If you’re due for a replacement unit rather than another cleaning, our roundup of the best camper AC units compares top rooftop models side by side.
Common mistakes to avoid: washing a disposable filter, using high-pressure water on the fins, reinstalling damp parts, and skipping the drain path. The last one quietly traps condensate inside the unit and turns your ceiling into a drip source.
FAQs
How often should I clean my camper AC filter?
Full-time RVers should inspect and clean the filter at least once a month. Part-time users can stretch that to every few weeks of active use. Washable foam filters get cleaned with mild soap and water; disposable pleated filters get replaced every 2–3 months, never washed.
Can I use a pressure washer on the rooftop coils?
No. The aluminum fins are thin and bend under high pressure, which restricts airflow and kills cooling performance. High-pressure water can also force moisture into the fan motor and electrical components. Use low-pressure rinsing or a coil cleaner spray instead.
Why is water dripping inside my camper from the AC?
A blocked condensate drain is the most common cause. Debris and algae collect in the drain pan and holes, trapping water that backs up and overflows indoors. Clear the drain path during each coil cleaning to keep condensate flowing freely.
References & Sources
- Keystone RV. “Maintain Your RV’s Rooftop AC.” Official maintenance steps for shroud removal, fin combing, and reassembly.
- Lippert. “RV AC Maintenance.” Cleaning guidance for coils, filters, and mold treatment with vinegar solution.
- Camping World. “How to Maintain Your RV Air Conditioner.” Recommended monthly filter cleaning for full-time RVers.