Holds a Master’s degree in Engineering and is keen on her own home’s climate. Sometimes we think that Carolina owns every single product she writes about – that’s how profound and insightful her reviews always are.
For 8 years, Richard had been working as an HVAC specialist and AC unit installer since his student years. Now, he’s our main consultant on every technical aspect that may arise during our tests and research.
Last updated: January 17, 2021
House Weather is reader-supported. We may earn a commission through products purchased using links on this page. Learn more about our process here
As air passes through your AC before it is distributed into your space, dust and airborne particles are trapped in the components which include coils. This is why it is important to invest in the best AC coil cleaner that would improve the performance of your AC, prolong its lifespan and prevent accumulation of grime, debris and pathogens.
We reviewed 15 cleaning products of different types to give you a variety of options that would match your budget and needs. We later narrowed down to five AC coil cleaners that have been rated highly for their efficiency, durability, capacity and competitive pricing. Nu-Calgon Evaporator Power topped our list of recommendations because it is a versatile product that is effective in cleaning fan blades, drain lines and condenser fins as well as removing mold on evaporators. It holds one gallon of no-foam alkaline liquid that is concentrated. Owners also like the pleasant scent and the resultant renewed look of their air conditioners.
Before buying the best AC coil cleaner, you should consider the type of product since they come in form of spray or concentrated liquid that are either foaming or non-foam. Secondly, check the volume to choose the right quantity for you. Thirdly, determine what the AC coil cleaner is based on to avoid acid-based options that could corrode and damage your appliance. Lastly, find out the country of origin for quick shipping, quality control and convenient replacement. Our review includes a buying guide that expounds on these key factors, a comparison table and in-depth reviews of the features of each product.
Our Editor’s Choice is the bestselling coil cleaner for AC on Amazon. Nu-Calgon Evaporator Power is a green-colored alkaline based cleaner made of sodium xylenesulfonate and 2-butoxyethanol.
It comes in a bottle that holds one gallon of the no-foam concentrated liquid that should be diluted before use. The recommended ratio of cleaner to water is 1:3. After applying it, you can either let the dirt drain away through normal condensation or rinse it off with water in a spray bottle. The instructions advise users to wear protective clothing and eyewear during this process.
Nu-Calgon Evaporator Power is designed to clean indoor evaporator coils, pan and drain lines. It is a biodegradable cleaner that is approved by USDA.
You can use a spray bottle although a wand sprayer would be more effective in dispensing the coil cleaner in the innermost parts of an evaporator box.
Buyers have used it to clean their split AC systems and to eliminate odor from mold and mildew. Others who used it as an indoor AC coil cleaner noticed a drop in temperature as their appliances became more efficient in cooling. They also like the refreshing lemon scent.
A number of customers found this AC evaporator coil cleaner weak and ineffective. The manufacturer advises users to brush off caked dirt and lint on coils and treating the surface with Cal-Shield if you choose to rinse. Otherwise, this is a no-rinse product that utilizes condensed humidity from ambient air to flush away dirt and dust.
DWD2 Clean AIR AC Evaporator Coil Cleaner & Refresher is a gun spray foam detergent that doubles up as a cleaner and a refresher for automotive.
The foam uses a safe formulation that is non-toxic, non-corrosive and biodegradable. This is advantageous because you can apply it on other materials other than metal and there is no danger of inhaling harmful substances or emitting any fumes. A patented delivery system distributes the foam within the core of an evaporator for even cleaning. For best results, inject the foam between the blower fan and evaporator so it can be forced through the evaporator fins to deep clean any inhabiting mold.
Mold specialists endorse it as the best AC evaporator coil cleaner with proven capability to eliminate odor-causing mold and bacteria for an entire year.
The foaming AC cleaner is available in two different sizes of 12 and 8 ounces and you can also choose between unscented and a citrus scent.
You will need to drill a hole where you will inject the foam but the instructions feature colored illustrations that are clear to understand. We wish they could be as clear on what this product is based on. Otherwise, we appreciate the customer support for assisting buyers by marking the install location for this automotive evaporator cleaner. All you need to do is to send an under the dash picture of your car.
Some users may find the cost quiet high but DWD2 Clean AIR AC Evaporator Coil Cleaner & Refresher is a worthy investment that excels at removing mold and musty odor.
With this cleaner, you don’t have to remove the coils because it forms excellent foam that seeps into them to lift off grease, grime and muck embedded between the aluminum fins.
Nu-Coil Air Conditioner Condenser Coil Cleaner is available in a gallon of professional grade concentrated liquid that should be diluted in a ratio of 3 parts of the liquid for every 10 parts of water, or according to the amount of foam and your cleaning needs. Wait for a minimum of 10 minutes for the solution to foam. Although rinsing is not required, the manufacturer recommends light rinsing to remove any additional particles that might remain after normal condensation.
The locally-manufactured detergent is designed for external air conditioning coils. Nu-Coil Air Conditioner Condenser Coil Cleaner revamps condenser and evaporator coils as well as mechanical surfaces and permanent air filters made of metal.
A gallon is equivalent to 128 fluid ounces, so you can expect several applications that will last you for a while before you need to replace this outdoor AC coil cleaner which can also be safely used for indoor coils. A couple of buyers were disappointed to receive half of the liquid, but that seems a rare case.
Rectorseal Foam-A-Coil Coil Cleaner is a biodegradable detergent that comes in a gallon of gun concentrated foam liquid that provides several cleaning sessions when you dilute it. It is a powerful alkaline-based AC cleaner that successfully gets rid of oil and grease in evaporator and condenser coils and electronic and permanent air filters.
This is one of the best AC condenser coil cleaners for outdoor appliances because it does not strip off ICP black painted coils since it is not acidic-based. You can use it on aluminum, copper and ABS plastic components without corroding them. However, it takes more work to clean thick debris which is why some owners find its performance satisfactory.
In case this coil cleaner does not foam as several users report, remember that the ratio differs according to the amount of dirt you need to clean. One part of the cleaner should be mixed with 3 or 4 parts of water if there is plenty of gunk and grime and 6 to 10 parts of water for regular maintenance cleaning. Owners recommend using a low-pressure hose instead of a power sprayer when cleaning condenser coils to avoid damaging the fins. Another helpful tip that would make this product to foam is to put water in the pump sprayer, and then add the coil cleaner. Above all, resist the urge to exceed the recommended ratio of cleaner to water because it may damage the coils over time.
Lundmark Coil Cleen removes dirt and grime in AC coils, condensers and fins to increase the lifespan of your fan motor by reducing its workload. Buyers also use it to clean radiators and oil coolers and to eliminate the musty smell of evaporators in car ACs.
The no-foam coil cleaner spray is alkaline-based. It comes in a bottle with a volume of 32 ounces, and you can opt for an alternative quantity of one gallon.
Lundmark Coil Cleen is an affordable product that will provide great value for money by lowering your energy bills, keeping your air conditioner in peak performance and reducing the noise.
It is easy to use and the manufacturer has uploaded a helpful video on YouTube to walk you through the process. This is not a leave-in product so you need to rinse it afterwards. After spraying it on the surface, remember to allow some time for the gunk to loosen.
Buyers who recommend this product as the best rated ac coil cleaner like the improved air flow, shiny effects and its ability to quickly get rid of gunk, dirt and leaves trapped in their fan blades and AC coils. However, some of the users find the smell a bit strong.
What we liked:
2 volume options
Short cleaning time
Made in USA
What could be better:
Things to Consider
If you are shopping for the best coil cleaner for AC that will ensure you have clean healthy air and low utility bills, then you have come to the right place. Our comprehensive guide explains everything you need to know before making your purchase, including the most important features to look for. We have also added a brief FAQ segment where we discuss the most suitable products for mini-split systems and the safety precautions you should observe.
Why it’s essential to clean your air conditioner evaporator
Air conditioners trap debris, dirt and other harmful contaminants that can cause odor, allergies and other ailments.
A clogged AC prevents proper air circulation. This makes the system to overwork and overheat, and may damage the motor and fan compressor, affect heat transfer by the evaporator and cause refrigerant leakage, or block the drain pipe with sediments.
Investing in the best AC condenser coil cleaner is a worthwhile investment that will save you money on both AC repairs and energy costs. This is because the coil becomes 5 percent less efficient each time it collects 1/100th of an inch of dirt. According to the US Department of Energy, an inefficient AC system that struggles to draw heat will raise your utility bills by approximately 30 percent.
Regular maintenance with the best AC evaporator coil cleaner will promote circulation of clean air, keep your cooling system in top performance, extend its longevity by lessening wear and tear, and save you money on energy bills and repair. Lastly, your air conditioner will be much quieter.
Features to consider when choosing an AC coil cleaner
The following are the key features that define the best rated AC coil cleaners in the market. Learning about them and matching them to your specific needs will get you the right detergent for your appliance.
Type: concentrated or not?
Coil cleaners for ACs are available in watered down or concentrated formula. Concentrated cleaners require you to dilute them beforehand according to the amount of gunk. The ratio differs from one brand to another, but it is specified in the instructions that come with your coil cleaner. For example, Nu-Calgon Evaporator Power recommends 1:3 ratio of cleaner to water. For Rectorseal Foam-A-Coil Coil Cleaner, mix one part of the cleaner with 6 to 10 parts of water for routine maintenance and one part of cleaner for every 3 or 4 parts of water when deep cleaning. Concentrated AC coil cleaners are better at removing stubborn gunk since you can adjust the product to water ratio to match the level of cleaning needed. They also last longer because you only need a little amount per cleaning session.
Lundmark Coil Cleen and DWD2 Clean AIR AC Evaporator Coil Cleaner & Refresher are among the best indoor AC coil cleaners that come ready for use. Simply spray the detergent on the surface, wait for the recommended time, and then rinse it off or leave it in depending on the instructions. The spray models are effective at cleaning AC evaporator coils because you can pump the cleaner deeply into these hard-to-access components to remove embedded debris.
If it’s foaming
We have reviewed the best foaming AC cleaners as well as non-foam products. Contrary to popular thinking, too much foam does not necessarily translate to better cleaning. If anything, applying a lot of foam may prevent the detergent from reaching some surfaces. Having said that, a fair amount of foam plays a substantial cleaning role by extending the contact time between the cleaning agent and the surface. This allows the detergent to soak in, dissolve the caked debris and dislodge it.
Volume refers to the various container sizes available for AC coil cleaners. Since ACs installed outside trap a large amount of dust, leaves and dirt in the condenser coil fins, consider a bigger size for the best outdoor AC coil cleaner. Nu-Coil Air Conditioner Condenser Coil Cleaner and Rectorseal Foam-A-Coil Coil Cleaner would be great choices since they are both available in the size of one gallon. You may also need a large size if you use your air conditioner frequently or if it is cooling a sizeable amount of space.
The evaporator and condenser coils in air conditioners are generally made of copper while the delicate fins are made of aluminum. While acid-based cleaners can remove dirt buildup easily, they can cause chipping of paint or corrosion of coils due to their aggressive contents. The best indoor AC coil cleaners are alkaline-based products which provide a gentler and safer alternative. Nu-Calgon Evaporator Power is an alkaline based cleaner derived from sodium xylenesulfonate which is an organic solvent that dissolves oil and grease, and 2-butoxyethanol, a form of alcohol that gets rid of water soluble pollutants.
Instead of chlorinated solvents which are damaging to the environment, consider non-toxic, non-corrosive and biodegradable AC coil cleaners that do not produce any fumes to avoid inhaling harmful substances, particularly when shopping for the best indoor AC coil cleaner where ventilation may be limited. Look for brands that are registered by NSF International or certified by USDA (United States Department of Agriculture) because they meet the required healthy and safety standards, including safe usage near food production.
Establishing where your intended AC coil cleaner is made enables you to buy a product that meets the strict health and safety standards set by NSF International and USDA. These authorized bodies also evaluate the contents, cleaning procedure and the performance of the product before approving it. Coil cleaners manufactured in America usually meet these criteria, and there are other regulations in place to protect consumers from harmful purchases. Buying brands made locally is advantageous because of the quick delivery, accessible customer support and convenient replacement of the product.
Other packaging options
Having a variety of sizes to choose from accommodates a wider range of budgets and cleaning needs. DWD2 Clean AIR AC Evaporator Coil Cleaner & Refresher offers scented and unscented options and two different volumes. It avails packages of 12 and 8 ounces, and AC evaporator coil cleaners that are either unscented or with a citrus scent. Lundmark Coil Cleen is another best rated AC coil cleaner that is available in two different volumes of 32 ounces and one gallon.
Lastly, you might receive an extra sprayer with your coil cleaner for AC that distributes the detergent evenly to cover the entire surface.
As mentioned previously, the contents of the AC coil cleaner will determine the type of pollutants it can effectively remove. We can also look at versatility in terms of compatible appliances, place of installation and safe application on diverse material such as aluminum, copper and ABS plastic surfaces. Some products, especially no-rinse cleaners, are specifically designed to clean indoor AC evaporator coil, but there are still a variety of brands that are suitable for both evaporator and condenser coils as well as other surfaces. Rectorseal Foam-A-Coil Coil Cleaner and Nu-Coil Air Conditioner Condenser Coil Cleaner are multipurpose detergents that can be applied on external condenser and evaporator coils, mechanical surfaces and permanent metal air filters. Since most people clean AC coils once or twice a year, such versatile cleaners are economical because they provide a one-size-fits-all solution that helps you to maintain several appliances and components instead of buying separate cleaning agents.
A coil cleaner that also eliminates odor caused by mold and bacteria would be preferable especially for ACs installed in basements where these contaminants thrive due to the high humidity.
Ease of use
The best rated AC coil cleaners come with clear instructions on application, timing and the cleaning procedures. This enables you to know the correct portions to make a mixture with concentrated products, the best method to distribute the detergent, and the time you should allow it to work without damaging the surface. It also lets you know the type of pollutants it is best suited for.
AC coil cleaners that come ready for use upon purchase and self-rinsing models like Nu-Calgon Evaporator Power that use condensation to drain away the removed particles are convenient because they shorten the cleaning time and require less effort.
Other models come with an additional sprayer that makes it easy to dispense the detergent while some rotate at 360 degrees to distribute the detergent to every nook and cranny of the coils.
Cleaning your air filter regularly will protect your AC coils from buildup of dirt, debris and particulates.
Your condenser coil is more prone to dust, dirt, soot and foliage if it is installed near a street, a restaurant or an industry with toxic emissions.
For outdoor applications, spray water on the condenser coil before using an outdoor AC coil cleaner.
Do not leave alkaline-based coil cleaners on the surface for longer than the recommended period because although they are non-corrosive, extending that time may damage the external layers of the coil after a while. Shortening the stated waiting time is not advisable either because it does not allow the detergent sufficient time to penetrate through the muck and grime.
You can use a soft-bristled brush to scrub off some of the dirt prior to using an outdoor AC coil cleaner.
Experts recommend cleaning your AC coils annually although it wouldn’t hurt to perform the task twice a year. Ultimately, the frequency will depend on your usage, the age and location of the AC, and the amount of particulate buildup in the system. Carrying out routine maintenance with the best rated AC coil cleaner will increase the efficiency of your system and increase its lifespan. It will also prevent odor from mold and mildew and accumulation of harmful airborne particles.
Mini-split units are also known as ductless split systems. As the name suggests, they do not require ductwork to function. This makes them the most suitable appliances for spot cooling. Most of the products we have featured are alkaline-based, so they make the best AC evaporator coil cleaners for these systems because they do not emit fumes or a strong smell when used indoors. They include Nu-Calgon Evaporator Power.
Unplug the appliance before cleaning. Wear protective clothing and eyewear to shield you from splashes and sprays. Apply a thin layer of the coil cleaner for AC and rinse it off, if required, to avoid corrosion of the surface. Confirm the recommended ratio of cleaner to water for your specific product and the mode of application. For instance, For instance, owners caution against a power sprayer when cleaning condenser coils to avoid damaging bending or flattening the fins when applying Rectorseal Foam-A-Coil Coil Cleaner. Instead, they recommend using a low-pressure hose. When diluting a concentrated coil cleaner, always put water first in the sprayer and then add the cleaner to it.
Nu-Calgon Evaporator Power is authorized by USDA for adhering to health and safety requirements. The alkaline based indoor AC coil cleaner comes in a container that holds one gallon of the concentrated liquid with a lemon scent. The cleaner to water ratio of 1:3 ensures a small amount goes a long way.
DWD2 Clean AIR AC Evaporator Coil Cleaner & Refresher is a dual-functional product that eliminates mold and bacteria and keeps your car smelling fresh. It also features a citrus scent although you can opt for unscented version. You can also buy the detergent in two different sizes. Finally, the Company’s exemplary customer support staff will help you identify where to install this AC evaporator coil cleaner with a patented deep cleaning system.
Nu-Coil Air Conditioner Condenser Coil Cleaner is the best outdoor AC coil cleaner that also cleans permanent metal air filters and mechanical surfaces without damage. This is a foaming professional grade concentrated liquid that will clear grease, grime and muck while saving you time and effort since rinsing is optional.