Due to the tight spacing between the coil fins, surface moisture from the cooling process, and the amount of air that flows across them, dirt, dust, debris and other pollutants can build up on the coil surfaces. Over time, this buildup reduces the system’s ability to transfer heat into and out of the home, thus reducing your system’s ability to provide summer cooling. In more extreme cases, dirty coils can also hinder or block the airflow that is so important to the entire process. This can result in having a less comfortable home and rising utility bills due to the lost energy efficiency. Even worse, dirty coils make the system work harder than intended and can result in shorter system life and potentially expensive repair bills. In short, the cleaner the air conditioning coil, the more efficient the system will operate.