How To Clean AC Evaporator Coils Inside House

If your air conditioner is performing inefficiently or has stopped working altogether, dirty evaporator coils are a possible cause.

But to keep your coils clean, you do not need to spend much money or get expert services. Instead, you can clean them yourself by combining a gentle cleanser and lukewarm water in a plastic container or a lawn sprayer. 

Allow a couple of minutes for the liquid to seep in and dislodge the dust and grime on the coils. After that, respray as required after wiping away any unsettled residue with a light brush or sponge.

How can you know if the process you’re following is safe and when it’s time to seek professional advice? 

Well, here’s a detailed guide that explains it all. Read on ahead as we answer how evaporator coils work, why they are essential, and how to clean them at home.

Where is the Evaporator Coil Located? 

An A-frame or pyramid-shaped arrangement of copper coils makes up an HVAC evaporator coil for a centralized AC system.

It is usually found near the indoor air handling unit of your air conditioner and is hidden under a metal cover in the section of your air conditioner located inside your home. 

Furthermore, this metal casing carrying the unit’s evaporator coils is usually hidden in a closet, loft, or other out-of-the-way location.

How to Clean the AC Evaporator Coils Inside your House?

The most straightforward approach to keeping the coils clean is using clean air filters in central air conditioners.

This is because the majority of the tiny particles that may create problems for your AC will be captured by the air filter. 

So, to keep your coils working efficiently, wash and change your air filters regularly. 

Additionally, while you could perhaps hire a professional HVAC specialist for cleaning AC evaporator coils for you, here are a few simple tips if you wish to do it yourself: 

  • Step 1: Switch off the HVAC system at the thermostat
  • Step 2: While cleaning, wear safety gear to keep the debris, pet dander, and other allergens out of your eyes 
  • Step 3: Loosen the screws securing the access panel so you can examine the evaporator coils
  • Step 4: Wipe the surface clean with a delicate washcloth to remove finer contaminants 
  • Step 5: If there are tenacious particles or if you generally want to guarantee vigorous cleaning, use a self-rising material explicitly made for this cleansing operation. However, make sure the brand you choose is designed exclusively for cleaning AC coils located within the indoor unit and is appropriate for plastic elements.

Repeat these steps every two to three months or even every month if you want a truly effective and helpful system.

Problems when the Evaporator and Condenser Coils Get Dirty 

Although you might think a bit of dirt is innocuous, the reverse is true regarding air conditioners. 

If your air conditioner’s evaporator and condenser coils are unclean, you’re likely to have several problems. This includes:

1. Ice Buildup on the Coil

When a coil is extremely unclean, it cannot capture the warm air blown over it. Additionally, the coil can frost up if there isn’t any warm air to counterbalance the refrigerant. 

This can prove harmful because if your coil becomes frozen when your air conditioning unit is running, it will burden your unit and may result in significant damage. 

If your coil is iced, your air conditioner’s compressor coil is especially susceptible to harm because it might heat up and burn out.

2. Increased Wear on the System

Since dirty evaporator coils make cooling your home more complex, your HVAC system will have to work harder and longer to adjust. As a result, you’ll have to pay a lot more for cooling as your unit will use more power than usual. 

Eventually, your system may also collapse.

3. Lowered Cooling Capacity

If your AC seems not to be running as well as it did at the beginning of the cooling season, it’s likely that dirty evaporator coils are at fault. 

In extreme circumstances, the dirty coils can cause ice or frost to form on the refrigerant pipes and the coil itself. So, even though you can switch off your air conditioner to allow the coils to defrost, you should also have a specialist come over and investigate the problem.

4. Lowered Heat Transfer

ACs remove humidity from the air and recycles filtered air that makes your house feel pleasant. However, indoor humidity cannot be controlled as effectively when filthy evaporator coils are used. 

5. Higher Energy Consumption

Dirt will make your air conditioner function ineffectively. You may feel as though your AC is continually running and still not making your room cool. 

When your air conditioner has to run for more extended periods, it naturally consumes more energy. Unfortunately, this implies you’ll have to pay extra to keep your house cool, and the harshest summer months could become a significant financial burden.

6. Higher Temperatures and Operating Pressures

Your home’s thermostat keeps track of the temperature and alerts your air conditioning unit when it’s time to turn on. 

Easy, right? 

However, a filthy evaporator coil might be a substantial issue because it is designed to work in cycles. It continues to function, attempting to fulfil its designated function, wearing itself down. So, the longer the rounds last, the filthier the coil becomes. 

If this continues too long, the system’s life will be cut short.

Benefits of Getting Evaporator Coils Cleaned

Evaporator coils that are dirty force your air conditioning unit to work harder, which raises your energy cost.

Thus, one advantage of keeping coils clean is that your property will cool faster when the coils are clean. However, this is not the only benefit. 

Other advantages include:

Improved Transfer of Heat

Dirt and grime accumulating on the evaporator coils or air handler of HVAC systems inevitably reduce heat transfer, requiring more power to maintain the required temperature. Particles on the coils thus hinder the performance and airflow.


The second benefit of cleansing evaporator coils is that it saves money. This is partly due to increased heat exchange. This is because less energy is used to regulate the temperature. 

Additionally, you can save money by investing in expert coil maintenance regularly. Not to forget, clean coils also reduce the likelihood of mechanical malfunction and save money on repair costs.

Decreased risk of System Failure

Dirty coils reduce the transfer efficiency even in the best-case scenario. And in the worst-case scenario, continuous evaporator coil overheating might destroy system components and cause the entire unit to collapse. 

Prolonged Equipment Lifespan

An HVAC unit’s longevity is extended by proper maintenance and regular cleaning, which reduces the chance of constituent damage. HVAC systems that are maintained regularly and undergo annual inspections survive longer. 

Alternative Ways to Clean AC Evaporator Coils

Aside from the approach mentioned above, you can clean the filthy evaporator coils in your AC unit using the techniques listed below.

1. Using Compressed Air

Light accumulations of dirt and other substances can be eliminated by blowing them out of the coil with compressed air. This is done by placing the air nose near the bottom edge of the debris for any remaining stubborn particles. 

Additionally, guide it through the fins at a right angle or straight through if you’re utilizing high-pressure air. This way, your fins will not be damaged. 

Also, remember that grit, grime, and debris should not be blown into the indoor air handling unit, the duct network, or the living areas of your home. Instead, use a vacuum cleaner to collect the particles as they are eliminated if required.

2. Using a Brush

Brush cleaning evaporator coils can be a useful approach for eliminating modest dirt buildups. It allows for liquids or chemicals to be used and gives you more control over how much force is exerted on the fins and reels. 

This is useful as it removes the tougher-to-remove particles. However, hard-bristle brushes and cable brushes should be avoided since they can injure the fins.

3. Using Commercial Cleaners

Evaporator coils may be cleaned with various professional cleansers from various brands. The most prominent commercial cleaner is a foaming type that detoxifies and empties the unit’s drain pan. 

4. Using Mild Detergents and Water

Instead of a professional cleaner, you could also clean the coils with warm soapy water. Begin by combining lukewarm water and a mild cleaner in a squeeze bottle, handheld sprayer, or lawn sprayer.

Thereafter, spray the fluid and detergent solution on the evaporator coils and allow a few minutes for the solution to release the particles. Then, reapply and wipe out the loosened particles with a soft brush or cloth.

5. Heavy-Duty Cleaning

Intense solvents or heavy-duty cleaning procedures, such as a steam cleaner or a force washer, may be required if the evaporator coils are extremely unclean. 

The approach may also necessitate changes to your air conditioning system, such as coil replacement, refrigerant channel severing, reattachment, refrigerant channel vacuum replacement, and device refrigerant refilling.


If your central air conditioning unit isn’t operating as effectively as it should, the issue could be a congested evaporator coil. 

The evaporator coil, which is housed deep within the internal cabinet of your central AC or heat pump, can become blocked with dirt, debris, and junk over time. Mold, fungus, and slime can also sprout on the coil, causing your system to malfunction.

Thus, cleaning your AC coils thoroughly is essential for the proper functioning of your air conditioning unit and to avoid more severe damage. 


How do you clean indoor AC evaporator coils?

Cleaning indoor AC evaporator coils with a mild detergent and hose is ideal as it has a low chance of harming the evaporator coils compared to using chemicals. 

So, spray the mixture on the coils and let it remain for a few moments to dislodge the grime. Thereafter, reapply as needed after wiping away any unsettled material with a gentle cloth.

What is the difference between condenser coils and evaporator coils? 

The evaporator coil is a component of an AC system that cools indoor air by eliminating moisture and heat. 

On the other hand, the heat is transferred to the condenser coils, which disperse it outdoors. Thus, the evaporator coil functions with a condenser coil to conclude the heat exchange process that creates cool air, but both are different components.

What can I use to clean my evaporator coil?

To clean an evaporator coil, all you need is a soft bristle brush, a light dishwashing solution, warm distilled water, a spray bottle, and white vinegar. 

How to clean evaporator coils in split AC? 

While there are a variety of professionally available coil cleaning treatments, split air conditioner coils can be cleaned using a basic household detergent and water mixture. 

Additionally, a low-pressure sprayer should sprinkle the concoction onto the coil. Allow the coil to drain naturally or lightly rinse it with a garden hose. 

This procedure can be performed as many times as required.

How do I clean the inside of my air conditioner fins?

The best method is to clean the evaporator and condenser fins with an HVAC fin comb and an air conditioning fin comb. It is a tiny instrument with soft bristles used to clean your air conditioner’s external and internal fins with care.

What will happen if an evaporator coil gets dirty? 

A filthy coil can cause your air conditioner to stop working altogether. This can happen when condensation develops on the dust and freezes when the air conditioner runs. 

The accumulation of frost prevents heat transfer and results in the air conditioning system breaking down.

Can I use Simple Green to clean my AC evaporator coils?

Simple Green is a multi-purpose cleaner that can be employed to clean your air conditioner’s coil. 

To use it, spray your air conditioner with a hose, being careful not to get any water on the electrical circuits within the access panel. Thereafter, squirt the coils with Simple Green.

How often should AC evaporator coils be cleaned? 

When the AC coils get filthy, they’re supposed to be cleaned. The frequency depends on how frequently you change the filters and the level of dirt and debris in your home. 

Moreover, it is best to have an HVAC specialist inspect your entire ductwork system at least once per year. 

Does bleach harm evaporator coils?

Copper or aluminum are commonly used in evaporator coils. So, if your evaporator coil gets into contact with a corrosive agent like vinegar or bleach, it’ll rust! 

But if you still wish to use bleach to clean your AC evaporator coils, be very careful. It only takes ten minutes, and you must be confident that you can rinse efficiently. Any shortcuts taken or errors made can prove disastrous.

How long before I can turn on the AC after coil cleaning?

Wait at least five minutes after turning off the air conditioner if you’ve switched it off at the thermostat. You must give the compressor time to “decompress” after it has been turned off. Moreover, the motor will be stressed if you switch it on too quickly.