How to Clean an Outside Air Conditioner Unit—Without Paying a Pro

Feb 21, 2024

Spring is the perfect time for an AC tune-up, before the heat of the Bay Area summer sets in. Your outdoor air conditioning unit has been standing up to the elements throughout the colder months, collecting dirt and debris around its cooling fins and condenser coils, acting like a fuzzy wool blanket that prevents the heat from escaping. A dirty condenser unit reduces the overall energy efficiency of your system and can cause your AC unit to overheat and shut down.

What Does an Air Conditioner Condenser Do?

The A/C condenser helps your system dissipate heat more efficiently, much like the radiator in a vehicle. It releases heat that the pressurized refrigerant absorbs from your indoor air. The condenser unit is an important part of your AC unit's refrigeration cycle

As the refrigerant in your system absorbs heat, it turns into a gas. The compressor pressurizes the refrigerant and sends it to the condenser coils in the outside unit. A condenser fan blows air over these outdoor coils to release heat energy to the outside air. As the refrigerant cools, it returns to a liquid state. The cooler refrigerant travels back to the evaporator and removes the heat and humidity from the inside of your home, and the process continues.

Unfortunately, if your outdoor unit is clogged and impedes airflow, it’s harder for the refrigerant to release the heat. Not only will it take longer for the air conditioner to cool your home, but you’ll also see higher utility bills. A lack of proper airflow around the outdoor condenser coils can lead to system failure — usually on one of the hottest days of the year.

How To Clean an Outside Air Conditioner Unit

Regular cleaning and maintenance can keep your outdoor AC unit working efficiently throughout the summer. DIY condenser unit maintenance is an easy task with the right tools and know-how. Following are some of the tools and general steps for cleaning your outdoor AC unit — refer to your manufacturer’s manual for specifics related to your model.

To clean your outside air conditioner unit, you’ll need the following tools:

  • Air conditioner coil cleaner (follow your air conditioner manufacturer’s recommendations when selecting a cleaning agent)

  • Vacuum cleaner with soft-brush attachment

  • Water hose with sprayer

  • Work clothes, gloves, and eye protection

  • A fin comb

Then, follow these general steps, according to the manufacturer’s instructions:

Step 1: Turn the thermostat to “off.”

Step 2: Find the electrical disconnect (a metal box) near your outside unit, usually located on an exterior wall. Open the electrical disconnect and find the switch that turns off the air conditioner. This may be a pullout switch or a circuit breaker shutoff. Simply pull the plug out or flip the switch to the “off” position.

Step 3: Use gloved hands to remove any large pieces of debris on or around the outdoor unit.

Step 4: Carefully vacuum the condenser fins with a soft-brush attachment. Be careful not to bend the fins — if any are bent, straighten them with a fin comb.

Step 5: Gently spray the unit with your hose to clean off loose debris like grass and leaves.

Step 7: Spray the outside of the unit with the coil cleaner, and wait 10 to 15 minutes. The cleaner will foam and bond with the dirt on the coils, making it easy to rinse away.

Step 8: Rinse off the coil cleaner with the hose.

Do this task at least once a year — ideally in the spring — and check it throughout the summer, rinsing it off as needed.

Want To Keep Your Air Conditioner Energy Efficient?

Cleaning the air conditioner’s outside unit is just one of many tasks that need to be done to maintain your system’s energy efficiency.

To keep your air conditioner clean and energy efficient all season long, schedule professional AC maintenance every spring, which includes cleaning the outdoor condenser unit. Sign up for our HVAC maintenance plan, and we’ll come out like clockwork each spring. You’ll never have to remember to schedule your seasonal tune-ups again.

Once a certified HVAC technician has performed maintenance, you probably won’t have to worry about cleaning your outdoor unit again for another few months. Still, it’s a good idea to supplement professional HVAC tune-ups with some DIY maintenance of your own. Check the outdoor unit for debris after periods of high winds or storms. Maintain a plant-free zone of 18 inches around the unit for optimal airflow.

Check out our maintenance checklist to see everything we do during an AC tune-up and safety inspection. This includes cleaning your indoor and outdoor units. Schedule your $88 air conditioner tune-up today!

Service Champions is known for friendly, on-time heating and air conditioning service throughout the East Bay, South Bay, and Sacramento areas. Contact us for AC maintenance, including a thorough tune-up and 21-point cleaning.

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