What effect does a dirty prefilter have on the cooling system?

Within a cooling system, the prefilter plays a crucial role in ensuring that air quality is maintained and that the system operates effectively. When the prefilter becomes dirty, it can restrict airflow entering the system. This restriction leads to a situation where the cooling coil does not receive adequate airflow to perform its function effectively.

As the airflow decreases, the temperature of the cooling coil can drop significantly, potentially causing the moisture in the air that passes over the coil to freeze. This results in frost buildup on the cooling coil itself. When frost accumulates, it can further impede airflow, creating a cycle that exacerbates the issue and may ultimately lead to reduced cooling performance or even system failure.

In contrast to this correct choice, asserting that a dirty prefilter improves efficiency would contradict the fundamental principle of good airflow being necessary for optimal operation. Similarly, while excessive buildup might lead to overheating due to restricted airflow, the direct consequence is more accurately related to frost formation. Making maintenance easier does not occur with a dirty prefilter, as maintenance issues tend to increase with neglect.