Cleaning Your Outdoor AC Unit

AC condenser unit in front of brick wall
Cleaning an outside AC unit can keep your heating and cooling system running efficiently while extending its lifespan. At Aire Serv, we know many homeowners want to know how to clean an outside AC unit not only in an effort to improve efficiency, but to save money as well. If you're the do-it-yourself type who would rather tackle the job yourself than hire a professional, we have a few tips we think you'll find useful!

How Often Should You Clean the Outside Unit of AC System?

For most homeowners twice yearly is sufficient, once before the summer season sets in and you'll be cooling your home, and once during fall before cold temperatures set in and it's time to switch to heat mode.

What Tools/Supplies Will You Need When Cleaning an Outside AC Unit?

In most cases the following tools are all you'll need:

  • Garden hose
  • Shop vacuum
  • Screwdriver
  • Rags
  • Replacement filter
  • Pipe cleaner or soft-bristled brush
  • Fin comb


In addition to cleaning your unit, you'll want to remove any leaves, branches, sticks or other debris that may be around or on your outdoor AC unit. It's also important to keep in mind that plants or shrubs should be kept a reasonable distance away from the unit so you enjoy better air flow, and therefore improved efficiency. From pine needles and leaves to gum balls, pine cones and tall weeds or other plants/objects, make sure the space surrounding your unit and the unit itself is clear and clean. You'll also want to take a look to determine whether your AC unit is sitting level.

Now You're Ready to Clean!

  • One essential note: Make sure the power to your outside unit is turned off before you begin cleaning.
  • For any debris you couldn't clear away from the unit, a wet/dry vacuum with soft-bristled attachment can capture any dust, dirt, or other small debris from your unit and within the fins.
  • If you notice fins are bent, a fin comb or even a butter knife or other thin object is effective for straightening them back to their original position.
  • Locate the AC filter and remove it, washing with a strong spray from the garden hose if you have the reusable type. If your filter is one that's made of fiber or cardboard, buy a new one to replace the dirty one.
  • The panel that includes the vent openings is normally the top access panel, which you'll want to remove by taking out screws. Carefully place the access panel aside.
  • Take a look at the condenser coils inspecting for dust, dirt, debris and other build-up that can impact operation. A shop vac is great for vacuuming away debris, and once you've removed as much as possible with the vacuum simply rinse with the garden hose to clean away any remaining debris. Be careful when vacuuming to ensure you don't damage or bend coils or fins.
  • A wet rag is all that's necessary in most cases to clean fan blades. Check the fan vents and vacuum or wipe away any build-up of debris.
  • Now you're ready to replace the access panel. Simply screw it back in place, and turn the power to your unit back on.

Cleaning an outside AC unit isn't all that challenging, but the time and effort spent will be well worth it considering enhanced energy efficiency and the comfort your family will enjoy whether summer or winter.

At Aire Serv, our home comfort designers know how to clean an outside AC unit! If you prefer not to handle this project on your own, give us a call today.