how to clean ac coils

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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

5 Best AC Coil Cleaners to Keep Your Unit in Top-Notch Condition

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

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.

On the other hand, DWD2 Clean AIR AC Evaporator Coil Cleaner & Refresher which is available in quantities of 8 and 12 ounces would be the ideal choice for removing lint and dirt from RV condenser coils.

5 Best AC Coil Cleaners to Keep Your Unit in Top-Notch Condition

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.

Another reason you should evaluate the contents is because different detergents vary in their effectiveness in removing specific contaminants. As an illustration, Rectorseal Foam-A-Coil Coil Cleaner is outstanding in eliminating oil and grease whereas DWD2 Clean AIR AC Evaporator Coil Cleaner & Refresher excels at getting rid of odor and mold for up to a year.

Manufacturer

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.

Versatility

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

5 Best AC Coil Cleaners to Keep Your Unit in Top-Notch Condition

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.

Additional tips

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.