What Can I Use to Clean My Evaporator Coil?

Your evaporator coil is an essential component of your air conditioning system and keeping it clean is critical to keeping your home cool and comfortable.

Before beginning, unscrew and remove the evaporator coil access panel by unscrewing. Next, use a nylon scrub brush to remove any large chunks of dirt using short brush strokes to avoid bending and damage to aluminum fins.

1. Compressed Air

If the buildup on your evaporator coil is light enough, compressed air alone might suffice in cleaning it up. With your garden hose sprayer set to wide spray mode and starting on one side of the cabinet blowing clinging debris free from its fins with compressed air may suffice to get them looking their best again. Once most debris has been eliminated apply a light coating of cleaner (according to any instructions on the can), then soak your nylon brush before brushing the aluminum fins from top down starting at the top working downwards until all parts have been covered – taking great care not to scratching surfaces that might otherwise corroded areas where corrosion might exist before using compressed air for best results.

If there is some remaining dirt or grime, use your toothbrush to gently work away at any remaining gunk. For heavier buildup, soak a nylon brush in cleaner and use this to scrub off any remaining residue from the fins.

Nu-Calgon foaming coil cleaner is an excellent non-sudsing cleanser that quickly and safely liquifies grease and oil on contact, eliminating the need for rinse. Spray an adequate coating of cleaner onto the evaporator coil, allow it to set for 15 minutes, then repeat this step if necessary.

An effective alternative is mixing some detergent with water in a spray bottle and using this as an evaporator coil cleaning agent – this approach may prove just as efficient but is often less costly.

Before beginning, make sure you switch off AC power at the electrical breaker and wear rubber gloves to protect yourself from any cleaning solutions that might leak out. If your coil is heavily soiled, it would be wiser to hire a local heating and cooling company who specializes in HVAC services to complete this task properly. They have all of the knowledge and expertise needed to restore it back to original condition quickly while also offering other HVAC services as needed.

2. Commercial Cleaners

There are various commercial cleaners that can be used as effective evaporator coil cleaners, often found at your local hardware store. When applying this type of product, make sure to carefully follow its manufacturer’s instructions – usually spraying over coil and leaving for several minutes before rinsing with water is effective. It is also essential to wear eye protection when spraying these chemicals, and use a shop vac as recommended to collect dirt as it dislodges from coil.

Prior to working on a coil, it is essential that electricity be turned off. This will help avoid any potential damage to the blower motor and other electrical components of the unit. Furthermore, opening windows is recommended to help ventilate the room during this process and to help avoid carbon monoxide build-up within your home.

Dependent upon the severity of dirt build-up, it may be necessary to disassemble the fan assembly in order to gain access to its coils. This can be accomplished by unscrewing any screws holding it in place. Once complete, ensure all screws are put away safely in an easily retrievable location so they can be reattached later if required; also consider wrapping each of their screw holes with foam tape so as not to become dirty again in future use.

Once the coils have been cleaned, they can be reassembled and the air conditioning unit powered up again. As part of a good practice plan, cover panels and grilles removed during cleaning should also be reinstated as part of this step.

If your coils are covered with light dirt, compressed air is an effective solution for cleaning them off. Simply direct your compressor at an 90-degree angle over them so as to extract build-up without damage to fins or further embedding buildup into them through force of air pressure. Keeping the nozzle close by ensures no further embedded build-up in fins occurs as a result of powerful airflow force.

3. Mild Detergents and Water

Evaporator coils collect contaminants as they dehumidify indoor air, which if left alone can significantly diminish their ability to absorb humidity from the air and reduce efficiency. Some homeowners and HVAC companies attempt to clean evaporator coils quickly using compressed air, however this could create dust, dirt (and possibly mold) being spread around – something we strongly disagree with – this air should instead flow from cleaner side of coil towards dirtier one and vice versa.

Alternately, homeowners can spray their coils with non-sudsing mild detergent mixed with water for an efficient method to clean most buildup without damaging their delicate fins. If heavy dirt accumulations persists on a coil, a brush designed for coils (not ordinary household brushes which may damage fins) should be used to gently brush away dirt from its coil. For optimal results use a soft bristled brush designed specifically for coils (rather than using regular household ones that could bend fins) when cleaning them regularly.

Nu-Calgon makes an effective foaming no-rinse cleaner that’s suitable for metal and plastic drain pans; its foam is highly-rated. When using this approach, make sure the product is indoor-safe and does not contain acids which could damage copper used in evaporator coils and condenser coils.

To apply cleaner, remove the access panel, sweep away loose debris, wipe down coils, spray a moderate coating of cleaner onto them and leave for a few minutes before wiping with clean water to allow it to sit on them and foam up – breaking down grease or organic growth and draining down into drain pan. When finished rinsing off with clean water to finish drying.

Once your coil has been cleaned, reattach any parts that were removed during maintenance and install the access panel back on it. Switch on your AC at the thermostat, but wait to allow it to run until all surfaces surrounding your coil and system have completely dried before turning on your air conditioning unit.

4. Foaming Cleaners

Commercially produced cleaners exist that can help to easily and safely clean an evaporator coil without having to take it all apart. Aerosol cleaners make it simple and effortless to spray them directly onto the coils; foaming action works to dislodge dirt and grime from coil fins while being much safer than more toxic chemicals that require protective gear for use.

Before beginning to clean an evaporator coil, it is vitally important that all power be shut off – either by switching the breaker off or pressing down on the lever near the coil. Furthermore, turning off your air conditioner fan may help minimize dust entering your system during cleaning process.

Most coil cleaners recommended for outdoor coil cleaning are either acid or alkaline-based; however, neutral coil cleaners have also proven highly effective and safer to use than similar products. They typically feature an 8 pH scale pH and work by dissolving grease and oil deposits from coil surfaces. Such cleaners should generally be considered safer to use outdoors than most alternatives and therefore make an excellent choice for coil maintenance tasks.

Foaming cleaners can help get rid of stubborn grime on an AC coil by penetrating into crevices and other hard to reach areas. While foaming cleaners cannot replace thoroughly rinsing an AC coil, they’re an invaluable addition to your tool kit when trying to tackle hard-packed grime build-up.

Nu-Calgon Coil Cleaner and Lennox Evap Foam are two popular foaming coil cleaners. Both contain low amounts of acidity, can self-rinse when properly diluted and contain corrosion inhibitors; before applying them directly to a coil it’s wise to test them on some cheap plastic such as a drain pan line or water valve before doing so; if found unsafe for plastic use further diluting or using indoors is recommended.