An AC unit has a working principle that is based on transfer of heat from the inside to the outside environment. This process of exchanging heat is done through the AC coils. Learning how to clean these coils can significantly increase the service life of your AC. Two main types of coils are used in air conditioning units:
This coil is normally placed on the outdoor component of the AC unit. It is made up of aluminum and structurally covers the AC compressor. A fan is usually fixed inside the system to help in moving air across the condenser coils. These types of coils are usually affected by debris from outdoor activities such as lawn mowing and other sources such as trees and dust.
This coil is fixed inside the air conditioning unit at the junction of the main duct which is located above the furnace. Evaporator coils are responsible for changing the state of the refrigerant from liquid to gaseous.
The entire process of air conditioning is based on the refrigerant cycle and change of state. From the evaporator coils, the refrigerant is changed to gas which is then pushed through the compressor. The compressor puts the gas under high pressure thereby increasing its temperature and then releasing it to the condenser coils. At the condenser coil level, the refrigerant is changed from hot gas back into liquid that goes all the way to the evaporator coil.
Coils become dirty with time and this can affect the working cycle of the AC. The compressor can fail and this can cause the AC to glide to a halt. This means regularly cleaning your coils not only increases the lifespan of the system but also its efficiency.
Steps in Cleaning the Coils
Before venturing into the coil cleaning task, ensure you have the necessary equipment which includes a soft brush, grass shears, fin comb, coil cleaner, pry bar and carpenter’s level.
Start by removing the weeds, trailing plants, and grass around the condenser. Then use the coil cleaner to clean and remove dirt around the condenser coils. Use a soft brush to clean the fins and remove any dirt that may have collected there. The fin comb should be used to straighten the fins. Using the carpenter’s level, check whether the level of the condenser unit is horizontal or not. You can easily do this by checking the level of the concrete pad on which the condenser rests. If the condenser is not horizontal, use shims and the pry bar to ensure it is level.
These coils do not need regular cleaning like the condenser coils because they are not as exposed to the elements. They can just be cleaned once a year. To clean the evaporator coil, you need a different set of equipment including household bleach, a large hand mirror, a stiff brush and a screwdriver.
First, remove the foil wrapped insulation fixed at the front of plenum to get to the access plate. Using a screwdriver, remove this plate to access the evaporator coils. Use the stiff brush to clean the coils and make use of the mirror to help you see the dust. Ensure all parts of the coil are reached and pour the household bleach into the weep holes of the evaporator tray to help prevent a buildup of mold and fungus.
Ensure all parts are returned to their places after the entire cleaning process. Always exercise caution when doing the cleaning.