Skip to Content
Serving West Austin & Surrounding Areas
Top

DIY Cleaning for Indoor Evaporator & Outdoor AC Condenser Coils

dirty coils
|

To clean the coils on your AC unit, you’ll need to know a few things about the coils; how to access them, how to handle them, and what tools you’ll need. Before beginning, we recommend gathering all the tools you’ll need throughout the process. As with any electrical equipment in your home, make sure the electricity is off. Do this by accessing the circuit breaking, the small metal box on the side of your house.

How To Access Your AC Coils
Your AC system has two types of coils: the evaporator coil and the condenser coil. Your evaporator coils are located inside the indoor air handler and the condenser coils are located in the outdoor unit.

The air handler housing your AC’s evaporator coils will be located in the attic, basement, garage, or inside a utility closet. It has a removable access panel, which can be opened with a screwdriver. The evaporator coil forms an “A” shape.

To access the condenser coils, remove the protective top and/or side panels using a cordless drill or a screwdriver. The condenser coils surround the entire AC unit.

“A” Shape Evaporator Coil

Outside Condenser Unit

Proper Handling of AC Coils
Your AC’s coils are located behind delicate metal strips called fins. When cleaning the coils, it’s very important not to touch the fins forcefully, as they are easily bent and damaged.

closeup of air conditioner metal fins

Closeup of AC Coil Fins

Recommended Tools For Cleaning AC Coils
Solvent AC coil cleaner or detergent soap
Screwdriver
Hose and spray nozzle
Soft-bristle brush
Air conditioner fin comb
Flashlight or headlamp
Compressed air
Water spray bottle
Rags

How to Clean AC Condenser Coils On the Outside Unit

1. Turn the AC unit off using the breaker switch
2. Remove the protective grilles
3. Remove any larger debris such as sticks and leaves that have collected at the bottom over time
4. Using a soft-bristle brush, clean the fins on the outside of your unit in an upward or downward motion – never side to side
5. Spray a foaming cleanser, soapy cleaning solution, or a solvent cleanser such as Simply Green on all four sides of the inside of the unit
6. Allow 5-15 minutes for the cleanser to soak the fins; do not touch the fins
7. Using a garden hose and spray nozzle, spray the unit from the inside outward at a downward angle, being careful to avoid too much pressure
8. Hose off the outside of the unit from the top down without directing any pressure back inside the unit
9. Inspect the fins for damage and use the fin comb to straighten any bent coil fins. To do this, insert the tines of the comb and move the tool up and down
10. Let the unit dry out
11. Reassemble the protective covers
12. Turn the system back on

Note if your AC’s fan assembly is located at the top of the unit, it may be difficult to open the condenser without risking electrical damage. We recommend contacting a professional who can help.
The process to cleaning the evaporator coils is similar to cleaning the condenser coils. The difference is how you rinse the coils off after washing them. Instead of using a hose, you’ll use a spray bottle instead.

How To Clean The AC Evaporator Coils Inside the House

1. Make sure the AC is off using the breaker switch
2. Remove the air handler cover and locate the A-shaped coil
3. Using a soft-bristle brush, clean the fins on the outside of your unit in an upward or downward motion – never side to side
4. Spray both sides of the coil with AC coil cleaner, soapy cleaning solution, or a solvent cleanser such as Simply Green
5. Allow 5-10 minutes for the cleanser to soak the fins; do not touch the fins
6. Using a spray bottle, rinse the coils
7. Gently dry the unit using clean rags or towels
8. Inspect the fins for damage and use the fin comb to straighten any bent coil fins. To do this, insert the tines of the comb and move the tool up and down
9. Reassemble the protective covers
10. Turn the system back on

Using Compressed Air To Clean the Inside AC Coils

If the evaporator coils don’t contain a lot of buildup, you can simply use compressed air to clean them by directing a steady stream of air in the opposite direction of normal airflow across the coil.

Why Do I Need to Clean My AC’s Coils

The AC coils play a vital role in AC performance and the cooling process. Maintaining clean coils greatly reduces wear and tear and prevents early system failure.
Naturally over the course of the year, dirt, lawn clippings, and other debris will collect on the outside condenser. When they do, your unit loses efficiency and has to work harder to keep up. This can ultimately lead to the AC forming ice, which can damage your compressor and other parts of your HVAC system.

While your air handler is far less exposed, it isn’t 100-percent protected from dust and other fine particles, even with regular filter changes. When the evaporator coils get dirty, your AC becomes much less effective at generating cold air and dehumidifying your home.

How Often Should I Clean My AC Coils

How often your AC coils will need cleaning will depend on several factors including how demanding your AC use is, how often you change your filters, and how much dirt, dust, and debris you have in and around your home, however, cleaning is generally recommended at least on a yearly basis.

You can reduce dirt buildup on the coils by changing your air filters and hosing your outside unit off regularly.

How Long Does It Take To Clean AC Coils

Between collecting your items, taking apart and re-assembly of the unit, cleaning and cleanup, you can expect the process to take at least 2-3 hours.

While you may enjoy a good DIY project, for many people cleaning the AC coils simply isn’t a worthwhile endeavor. Because it’s such a time-consuming and delicate process and won’t exactly produce the kinds of results your friends and family will admire, it’s hardly surprising most homeowners don’t want to give up their precious free time to clean their AC.

Additionally, there’s much more to AC maintenance than clean coils. Proper AC maintenance includes a thermostat check, drain line inspection and cleaning, electrical tests, and more. During a professional tune-up, we’ll also inspect your AC coils and remove debris from the outdoor unit. Check out our popular Maintenance Plans to receive professional coil cleaning annually, a $191-$307 value.