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How to Spray Down and Clean Central Air Conditioner Unit Coils

Jason is a DIY-er. If it ain't broke, don't fix it. If it is, do it yourself!


Cleaning your central air conditioner is very important for your health and safety. If you have hot summer months and your central air conditioner is dirty, it will work harder and raise your utility bill quite a bit. In this article, I will explain some simple, yet effective methods for cleaning your air conditioner and making it operate more efficiently.

Dirty Air Condenser Unit

Dirty Air Condenser Unit

What Is the Condensing Unit or "Air Conditioner"?

Let's start with the outside condensing unit. A condensing unit comprises a compressor and a condenser coil. An air conditioner works to suck hot air out of a house. Indoor air circulates over the cooling coil and then cools the home.

How Does an Air Condenser Unit Get Dirty?

Air condensers have small fins around them that suck up all kinds of debris while running. It will accumulate dust, dirt, leaves, little pieces of grass cuttings, etc. This part of the air conditioner must be cleaned at least once a month for your air conditioner to operate effectively.

Intimidated by These Steps?

I'm not a licensed HVAC technician—just a DIY-er. If at any point in this process you're concerned my steps exceed your skill level, call your local technician. Better safe than sorry, and central AC ain't cheap!

Rinse the Detergent Off Your Condensor

Rinse the Detergent Off Your Condensor

How to Clean the Outdoor Condenser

  1. Start by shutting off the quick disconnect to the unit.
  2. After you've confirmed all power has ceased to the unit, spray the aluminum fins with a mild detergent like Palmolive, or even laundry soap.
  3. Mix water and the detergent in a spray bottle 50/50, and give the fins a good soaking. Let the mixture soak into the fins for five minutes or so.
  4. Take your garden sprayer and spray the fins out at a 45-degree angle.
  5. Spray until you are sure you have gotten all the dirt and grime out, or until the water runs clear.
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How to Clean the Evaporator Coils

Now that the outside condenser coil is cleaned, we need to clean the evaporator coil. The evaporator coil is also known as the "A" coil of our air conditioner. The evaporator coil is located inside the home above the furnace and main duct. Here's how to clean it.

  1. Make sure all power is off to the air conditioning unit and furnace.
  2. Find the panel that covers the evaporator coil—it is usually covered with foil tape. Remove the foil tape, and the screws holding on the panel. Once removed, you will see the evaporator coils.
  3. Start by using a shop vacuum to suck up all the dust and lint off of them.
  4. Next spray your solution of detergent and water all over the evaporator coils. Let them soak for awhile, then rinse. I suggest doing this gradually so your drip pan does not overflow so much. There will be some overflow, but not to worry.
  5. Once cleaned make sure the drip pan is free of debris, and put a little household bleach in the pan, and down the drain hose. This keeps mold from forming in the pan and pipe and blocking them.
  6. Replace the panel, screw and tape it back up.

We are finished with the evaporator coils!

Cleaning the air intake is a must.

Cleaning the air intake is a must.

How to Clean the Air Intake on a Condenser

You're probably wondering where the air intake on your air conditioner system is located. It's actually located along the base of your wall somewhere in your home (close to the evaporator!) Just look around for it, it should be easy to find.

This vent needs to be removed and cleaned with a small broom or shop vacuum.

  1. Vacuum all the dust and lint off of it.
  2. Then, take it outside and clean it with soap and water using a toothbrush or another small bristled brush.
  3. Let it dry.
  4. While it's drying, replace the filter with a new one. No sense in breathing musty air after cleaning the whole system!
  5. Let everything dry for at least 30 minutes.


Restore power and enjoy all the money you will save! Your air conditioner should now operate more efficiently.

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.

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