How to Clean Air Conditioner Coils

Is your air conditioner running, but your home still feels warm and muggy? Dirty coils might be the hidden culprit. Over time, dust, pollen, and debris can build up on your AC coils—causing your system to work harder and lose cooling power. This not only drives up your energy bills but can also shorten the life of your unit. 

The good news? Cleaning your air conditioner coils is a manageable task that can significantly boost your system’s efficiency. In this blog, we’ll walk you through the basics of what AC coils do, how to know when they’re dirty, how to clean them safely, and how to prevent future buildup. With a little help from Russett Southwest—or some well-informed DIY—you can keep your system running clean and cool all summer long.

What Are Air Conditioner Coils and Why They Matter

Your air conditioner relies on two key types of coils to keep your home cool: the evaporator coil and the condenser coil. Each plays an important role in the cooling process—and when either one gets dirty, your whole system can suffer.

The evaporator coil is located inside your home, usually near the air handler or furnace. It absorbs heat from the indoor air as refrigerant passes through it, effectively cooling the air before it’s circulated through your home. The condenser coil, located in the outdoor unit, releases that heat outside. As air blows over the coil, it helps the refrigerant shed heat and cycle back inside to cool again.

When dirt and debris build up on either coil, it acts like a blanket—reducing heat transfer and forcing your system to work harder. This not only decreases energy efficiency but can also lead to higher utility bills, poor indoor comfort, and unnecessary strain on your air conditioner.

That’s why keeping your coils clean is so important. It helps your AC run more efficiently, cool your home faster, and last longer—especially in Arizona’s demanding summer heat.

Signs Your Air Conditioner Coils Need Cleaning

Dirty coils don’t just sit quietly—they send out red flags that your AC isn’t working as well as it should. If you know what to look for, you can catch the issue early and clean the coils before it leads to bigger problems like system strain or a full breakdown.

Common Symptoms of Dirty Coils

• Weak airflow or reduced cooling performance
• Higher energy bills without a change in thermostat setting
• AC runs longer or struggles to cool the home evenly
• Ice buildup on the evaporator coil or refrigerant lines
• Musty odors or reduced indoor air quality
• Clicking or hissing sounds as the system fights to maintain performance

If you’re noticing any of these, dirty coils could be to blame—and cleaning them could make a big difference.

Causes of Coil Buildup

Dust and pollen circulating through the system, especially in high-desert environments like Arizona

• Clogged air filters that fail to catch debris before it reaches the coils
• Open windows and doors, which let unfiltered air and dirt inside
• Pet hair and dander, especially in homes with multiple animals
• Neglected maintenance, where dirt accumulates season after season

Routine cleaning and filter changes can help you avoid buildup and keep your system running efficiently.

How to Clean Air Conditioner Coils

Cleaning your air conditioner coils isn’t just for professionals—many homeowners can handle it themselves with a little preparation and the right tools. Whether you’re tackling the indoor evaporator coil or the outdoor condenser coil, it’s important to follow the proper steps to avoid damaging the system.

Tools You’ll Need

• Screwdriver: To remove the access panel or cover
• Soft brush or coil cleaning brush: To gently remove dust and dirt
• Spray bottle or foaming coil cleaner: Use water, mild detergent, or a no-rinse cleaner
• Wet/dry vacuum: For outdoor coil debris cleanup
• Fin comb (optional): To straighten bent coil fins
• Gloves and eye protection: For safety when working with cleaners

Step-by-Step Coil Cleaning Process

• Turn off the power to your air conditioner at the thermostat and breaker panel. Safety first!
• Access the coils by removing the cover from the indoor unit (for evaporator coils) or opening the outdoor condenser unit.
• Brush off loose dirt and debris with a soft brush or vacuum. Be gentle—coil fins are delicate.
• Apply coil cleaner evenly across the coils. Let it sit for the recommended time on the label.
• Rinse with water if using a rinse-required cleaner. For no-rinse products, let the cleaner foam up and drain off naturally.
• Clear out surrounding debris, like leaves, grass, or dust inside the condenser unit.
• Check for bent fins and use a fin comb to straighten them if needed.
• Reassemble the unit, restore power, and run the system to ensure it’s cooling properly.

Cleaning both your evaporator and condenser coils (at least once per year) can greatly improve airflow, reduce wear and tear, and restore cooling efficiency.

When to Call a Professional for Coil Cleaning

While some homeowners are comfortable handling basic AC maintenance, there are times when professional coil cleaning is the smarter and safer option. Air conditioners are complex systems, and working with internal components can pose risks—both to you and the equipment—if done incorrectly.

Here are a few situations where it’s best to bring in the pros:

• You’re not comfortable opening the unit or working near electrical components
• The coils are heavily clogged with dust, grease, or mold-like buildup
• You’ve noticed frozen coils, refrigerant issues, or poor airflow
• The system is running constantly or short cycling despite filter changes
• You want a full system tune-up, not just coil cleaning
• Your AC is under warranty, and DIY work might void the terms

A certified technician from Russett Southwest can clean your coils thoroughly, check for deeper issues, and improve your system’s efficiency without the guesswork. Professional cleaning also includes inspecting your refrigerant levels, fan motors, and overall system performance—something DIY cleaning can’t fully cover.

How to Prevent Dirty AC Coils in the Future

While cleaning your coils once a year is helpful, keeping them clean all year long starts with consistent preventative care. These simple maintenance habits can drastically reduce how quickly debris builds up—saving you time, money, and energy in the long run.

• Change your air filter regularly. Aim for every 1–3 months, depending on usage, pets, and allergies. A clean filter is your first defense against dust reaching your indoor coils.
• Keep the outdoor unit clear. Trim bushes, grass, and weeds around the condenser, and remove leaves or debris that could block airflow.
• Schedule annual professional maintenance. A yearly tune-up from Russett Southwest includes coil inspection and cleaning as part of a full-system checkup.
• Avoid running the AC with open windows or doors. This allows unfiltered air and outdoor particles to enter your system and collect on coils.
• Use high-efficiency or HEPA filters if you have pets, live in a dusty area, or suffer from allergies. These capture more particles before they reach the coils.
• Install a UV coil light system to reduce biological growth like mold or mildew on the evaporator coil.

Preventing coil buildup isn’t complicated—it just requires a few smart habits and seasonal attention to keep your AC running clean and cool.

Wrap-Up: Keep Your AC Coils Clean With Russett Southwest

Your air conditioner works hard to keep you comfortable—and clean coils are essential to making sure it runs efficiently and reliably. Whether it’s improving airflow, lowering energy bills, or extending your system’s lifespan, regular coil cleaning plays a big role in overall AC performance. While DIY cleaning is possible for many homeowners, sometimes it takes a professional touch to do the job right and spot issues you might miss.

If your AC is underperforming or it’s been a while since your last tune-up, let Russett Southwest help. Our expert technicians can clean your coils, optimize your system, and make sure your home stays cool and comfortable no matter how hot it gets outside.

Contact Russett Southwest today to schedule your coil cleaning or full AC maintenance service—your comfort depends on it!