How to clean the coils of an air conditioner yourself with a brush, shop vac and garden hose.

It’s easy to forget how much work your central air conditioner does everyday, and few appliances in your home run more than your AC. Yet, despite the heavy workload asked of your AC, few of us keep up with the necessary maintenance of our AC systems.

One important and easy-to-DIY maintenance item is cleaning your AC’s outdoor condenser coil. This post walks through the simple process of cleaning the coils of your AC. All you need for this projecte is a bench brush, a shop vac with a brush attachment, some dishwashing detergent and a garden hose.

#DIY #HVAC

Keeping the condenser coil of your central AC unit clean is super important.

The condenser coil unit of your AC is the box that sits outside and receives the warmed refrigerant from the inside part of your AC (evaporator coil) after it cools the air within your HVAC system.

The job of the condenser is to compress the refrigerant from its warmed gas state back into a cool liquid and release heat from the refrigerant into the environment.

This heat release (transfer) occurs in the condenser coils which act like a radiator, releasing heat into the air passed through the coils by the condenser fan. The process depends on a large volume of airflow across the condenser coils and therefore clean, unobstructed condenser coils.

To keep your AC functioning efficiently, quietly and at the lowest cost, the condenser coils need to be cleaned periodically. Most manufacturers recommend condenser coil cleaning at least annually.

As you’ll see shortly, my condenser coils are way overdue for cleaning. Several large cottonwood trees near our home release their seed fiber each spring, quickly creating a solid layer over the surface of our condenser coils.

The good news is that AC condenser coil cleaning is easy and only requires a few simple tools. Here are a few do’s and don’ts for cleaning your AC condenser coil.

AC Condenser Coil Cleaning Do’s:

Always turn off the power to the AC condenser unit before cleaning!
Do use a soft bench brush to remove heavy debris.
Do use a shop vacuum with a soft brush attachment to remove fine dust between the coil fins.
Do use a light mist from a garden hose to wash and rinse the condenser coils.
Do use a mild detergent like dish soap and a bench brush to degrease and wash the coils and fins.
Do use care when re-assembling the condenser grills to avoid pressing on and flattening the coil fins.

AC Condenser Coil Cleaning Don’ts:

Don’t service or clean your AC with the power on!
Don’t use high pressure water or a power washer to clean condenser coils – the high pressure. water can easily bend and flatten the delicate coil fins of the condenser.
Don’t use stiff brushes or tools that can damage and flatten condenser coil fins.
Don’t use flammable solvents, cleaners or fuels to clean condenser coils.

Overview | AC Condenser Coil Cleaning

Project Goal: Clean the condenser coils of your central AC system yourself.

Difficulty: Beginner

Time: 1 Hour

AC Condenser Coil Cleaning Cost: $10

Steps:

Gather Tools and Supplies.
Remove Condenser Grills.
Brush any heavy debris off of exterior to the condenser coil.
Vacuum the surface of the coils with a brush attachment.
Rinse, wash and then rinse the condenser coils with a garden hose and dish soap.
Reassemble the grills, restore power to the condenser.

Supplies List | AC Condenser Coil Cleaning

Dawn Dishwashing Soap

Tools List | AC Condenser Coil Cleaning

Steps | AC Condenser Coil Cleaning

Gather Tools and Supplies.

Gather shop vac, brush attachment, cordless driver/drill, bit set (many use a 5/16" nut driver bit), bench brush, bucket, dish soap, garden hose and sprayer attachment. Turn the power off to the AC condenser, either at the outside breaker or at the panel in the house.

Clean your AC coils with bench brush, shop vac, garden hose.

Remove Condenser Grills.

Using your tool of choice, remove the screws holding the side grills of the condenser, then remove the grills using care not to damage the thin coil fins of the condenser coil. Use the bench brush to clean the grills and set them aside.

Remove the condenser grills by removing the screws holding them in place.

Condenser grill being removed for cleaning after removing the mounting screws.

Brush the condenser grills clean using the bench brush.

Brush any heavy debris off of exterior to the condenser coil.

Using a soft bristle bench brush, gently brush the surface of the condenser coil clean. Brush in the direction of the coil fins - usually up and down.

Clean the surface of the condenser coil using a soft bench brush.

Brush the entire surface of the condenser coil to remove surface debris.

AC condenser coil surface contaminated with cottonwood seed fibers after the spring bloom.

Brush all four sides of the condenser coil clean.

Vacuum the surface of the coils with a brush attachment.

Using a shop vacuum with a soft brush attachment, carefully vacuum the entire condenser coil surface. Move the brush in the direction of the coil fins (usually up and down).

Shop vac with brush attachment cleaning the surface of an AC outdoor condenser coils.

Move vacuum brush in the same direction of the coil fins while cleaning.

Rinse, wash and then rinse the condenser coils with a garden hose and dish soap.

Use a garden hose with a gentle spray attachment to rinse the condenser coils, starting from the top and working to the bottom. Then, using a soft, synthetic bristle bench brush or similar, apply soapy water to the surface of the coils working top to bottom. Finally, using the garden hose adjusted to a soft spray, rinse the coils from top to bottom until the soap has cleared from the coils.

Using a gentle garden hose spray, gently rinse the condenser coils.

Prepare soapy water to clean the coils using dish soap.

Apply soapy water to the AC condenser coils using a synthetic bristle bench brush.

Rinse the soapy water from the condenser coils using a gentle spray from a garden hose.

Reassemble the grills, restore power to the condenser.

After the cleaning process is complete, reassemble the grill covers on the condenser. The grills fit together and often overlap at the seams. My Bryant unit uses tabs on the bottom of the grills that lock onto the bottom edge of the condenser frame. Once the grill panels are assembled, install the sheet metal screws. After reassembly, turn on power to the condenser unit.

Repeat the cleaning process at least every year and possibly more frequently if you have heavy contaminants in your environment. Schedule the cleaning after tree and grass blooms and before peak cooling season for your location.