NCCER Millwright Practice Exam

Excessive buildup of dirt on the blades of a cooling fan can lead to what?

1. Reduced efficiency

2. Increased power consumption

3. Creation of vibrations

4. Overheating

The correct answer is: Creation of vibrations

When dirt builds up on the blades of a cooling fan, it disrupts the airflow that the fan is designed to create. This accumulation of debris can lead to an imbalance in the fan's operation. As the blades become heavier and the shapes altered by the dirt, the fan operates less effectively, which can cause it to experience increased vibrations. These vibrations occur because the fan struggles to spin smoothly and maintain consistent performance due to the uneven weight distribution and aerodynamics caused by the dirt. While reduced efficiency, increased power consumption, and overheating are related effects that could result from poor airflow or malfunctioning cooling systems, they are not the primary issue associated directly with the buildup of dirt on fan blades. The creation of vibrations is the most immediate and direct consequence of such an accumulation, making it the correct answer.