Inside the home is the air handler, and within this unit resides the evaporator coil. This coil absorbs the heat from the air within the home, sending cooler air out in its place. These coils are partially protected by air conditioning filters, which should be replaced ever 30-90 days. But despite filtering, dirt and debris from the air flowing over the coils does land on the coil. It is important to clean off this dirt to keep the evaporator coil cleaners functioning properly, and ensure proper cooling of the building.