How to Clean AC Coils: A Step-by-Step Guide for Homeowners

Maintaining your home’s HVAC system is crucial for optimal performance and longevity. An essential part of this is cleaning the AC evaporator coils. These coils play a pivotal role in the cooling process, and neglecting them can lead to inefficiencies, increased energy costs, and potential breakdowns.

In this comprehensive guide, HVAC.com explores everything you need to know about AC evaporator coils, from understanding their function to how to clean AC coils.

What Are AC Evaporator Coils and How Do They Work?

The evaporator coils are a vital component of your air conditioning system, responsible for absorbing heat from the indoor air. They are located within your indoor air handler or furnace cabinet.

As warm air from your home circulates through the cooling system from the return ducts, it passes over the evaporator coils. Refrigerant within the coils absorbs heat from the air, and cooler air is circulated back into your home.

The Problem with Dirty Evaporator Coils

Over time, dust, dirt, and debris accumulate on the evaporator coils. This grime reduces the coil’s available surface area for heat exchange, and their ability to absorb heat from the air diminishes.

This reduction in heat absorption leads to an inefficient cooling process, causing the system to work harder to achieve the desired indoor temperature. As a result, the air conditioner must consume more energy to do its job, leading to higher utility bills.

Over time, this added strain on the system may contribute to premature wear and tear of components. Operating your air conditioner with dirty evaporator coils can potentially lead to more frequent breakdowns and the need for costly AC repairs.

How Often Should AC Evaporator Coils Be Cleaned?

Experts recommend cleaning AC evaporator coils at least once a year to prevent the buildup of dirt and debris. However, homes in dusty or high-pollen areas may require more frequent coil cleaning. It’s a good idea to take care of this maintenance task in the spring, before you start using your air conditioner regularly.

Regular visual inspections can also provide cues for how much to clean AC coils – if the coils appear visibly dirty or if you notice a decline in your system’s performance, it’s advisable to initiate the cleaning process promptly.

How to Clean Air Conditioner Coils in 9 Steps

Now that you understand the importance of cleaning AC evaporator coils, here’s a step-by-step guide on how to clean indoor AC coils.

Step 1: Gather Your Tools

Ensure you have the necessary tools on hand, including a coil cleaner or mild detergent solution, a soft-bristled brush, a wet/dry vacuum with a soft brush attachment, and gloves.

Step 2: Turn Off the AC’s Power

Shut off power to the air conditioning system at the circuit breaker to ensure your safety while cleaning the coils.

Step 3: Access the Coils

Most indoor units have an access panel that can be removed to reveal the evaporator coils. Consult your unit’s manual to locate and open this panel if needed.

Step 4: Brush Away Surface Debris

Use the vacuum and brush to gently remove any visible dirt or debris on the coils. Be careful not to use excess pressure, as doing so could damage the coils.

Step 5: Apply Coil Cleaner

If the coils are coated with tough grime that isn’t fully removed by the vacuum, spray them with a coil cleaner or a mild detergent and warm water solution. Use the brush to gently remove this buildup, then rinse the coils.

Step 6: Vacuum Away Residue

Use a wet/dry vacuum with a soft brush attachment to remove any remaining residue. This ensures a thorough cleaning without damaging the coils.

Step 7: Clean the Drip Pan

The drip pan located below the coils should also be cleaned, as it can accumulate debris from dirty coils. Use the vacuum to remove any matter, then flush the pan with clean water.

Step 8: Allow the Coils to Dry

If you had to use a coil cleaning solution to remove tough debris, make sure to allow time for the coils to dry. The evaporator coils must be fully dry before restarting the air conditioner.

Step 9: Power Up the Air Conditioner

Once the coils are clean and dry, reassemble the access panel and turn the power back on. Monitor your AC’s performance to ensure it’s running smoothly.

Professional Maintenance for Evaporator Coil Cleaning

While DIY is an option for how to clean AC coils, some homeowners may prefer leaving the task to the professionals. During a routine HVAC maintenance visit, technicians inspect and clean the evaporator coils, along with other essential components.

If you’re unsure about performing the task yourself or if your system requires more than a basic cleaning, it’s best to enlist the services of a qualified HVAC contractor.