In short: efficiency will go down (electric bill will go up), the evaporator coils might freeze up, and the life of the unit will be diminished.
Signs that your AC coils need cleaning include reduced cooling efficiency, longer cooling times, and higher energy bills. If you notice these issues, it's time to clean the coils.
This is totally cleanable. Try using a brush with a commercial coil cleaner or make one at home. You only need detergent and warm water. Mix them together and spray evenly on your evaporator coils. Leave it on for 5-10 minutes and then wipe off with a piece of cloth. Repeat the process and you should be good to go.
The AC coil cleaning cost is around $100 to $400 as of 2024, according to Homeguide (for an evaporator coil), and up to $700 to remove and clean the coil. Cleaning the condenser coil costs $75 to $230.
How Long Must I Wait After Coil Cleaning Before Turning On The Air Conditioner? Before using the air conditioner, make sure it is totally dry. After cleaning the coils, wait 30 to 60 minutes before turning on the air conditioner.
Homeowner: A new evaporator coil replacement costs $630 to $1,700 if it is still under warranty. Homeowner: An indoor AC coil replacement costs $1,230 to $3,700 if it is no longer under warranty.
Considering the extended system lifespan, sustained energy efficiency, lower operating costs, better comfort and reduced potential for extensive repair work, AC coil cleaning is a cost-effective way to care for your system.
Accessing Evaporator Coils
The evaporator coil of a split-system A/C is located inside the air handler, which is typically found in the utility closet, garage, basement or attic. There should be a removable access panel on the air handler that exposes the evaporator coil.
Dirty evaporator coil
Normally, the condensation drains outside and doesn't cause any problems. However, if your evaporator coil is dirty, then condensation can mix with the dirt to create mold, which would explain the musty smell.
The most obvious sign of a dirty evaporator coil is an overall drop in system pressure. As long as you know what constitutes a normal pressure for your system, you should be able to tell if the current pressure is below that level. If it is, a dirty evaporator coil is probably your culprit.
Replacing just the evaporator coil can lead to problems. A common rule of thumb in the industry is if your AC unit is over 8 years old, it may be more beneficial to replace the entire unit rather than a single component.
Brush Off Loose Debris: Using a soft brush or a specialized furnace coil brush, gently brush away any loose dirt or debris from the coils. Be gentle to avoid bending the fins or damaging the coils. Vacuum the Coils: Attach a soft brush to your vacuum cleaner and carefully vacuum the coils.
AC coil cleaning costs $100 to $400 on average, depending on the coil type, location, accessibility, and dirt buildup. Evaporator coil cleaning costs $100 to $400 to clean the coil in-place or $400 to $700 to remove and clean the coil. Condenser coil cleaning costs $75 to $230.
Dirty AC coils become insulated rather than able to release heat the system extracts from the air. The system will therefore struggle to cool your home. Indoor air can become more humid too, as the system won't be able to extract as much moisture, making things extremely uncomfortable in the summer.
First, check your filters and coils for dirt and debris that may be impeding airflow. Once you've cleaned the filters and coils, run the air conditioner with just the fan so that the ice accumulation can melt off. If the AC still doesn't blow cold air, it could be that refrigerant levels are too low.
While Dawn dish soap is a versatile cleaning agent, it's not recommended for cleaning AC coils due to its chemical composition. Household cleaners like Dawn may not effectively remove stubborn buildup and could potentially harm the coils or other components of the system.
Mix a simple detergent and warm water in a spray bottle or garden sprayer. Spray the solution onto the evaporator coils and give it a few minutes to soak in and loosen the dirt and debris. Wipe away any loosened material with a soft brush or cloth and reapply as needed.
Afterwards, fill the second spray bottle with a half-and-half mixture of white vinegar and distilled water. Use this bottle to spray the solution onto the evaporator coil.