Oilers/Plant Tenders (HHC) Civil Service Practice Exam

Aftercoolers are typically added to air compressor installations to achieve what function?

1. Increase efficiency

2. Condense moisture from compressed air

3. Reduce vibration

4. Enhance air delivery speed

The correct answer is: Condense moisture from compressed air

Aftercoolers are essential components in air compressor systems, primarily serving the function of condensing moisture from compressed air. When air is compressed, it heats up, and as it cools, moisture in the air can condense. If this moisture is not removed, it can lead to several issues, such as corrosion in piping and tools, impaired performance of downstream equipment, and reduced air quality. By using aftercoolers, the temperature of the compressed air is significantly reduced, which promotes the condensation of moisture. This moisture can then be drained away, ensuring that the compressed air remains dry and free from excess humidity. In this way, aftercoolers play a critical role in maintaining the quality of the compressed air and protecting the integrity of the entire system. While enhancing efficiency and reducing vibration may also play a role in the overall function of air compressors, these are secondary benefits compared to the vital task of moisture condensation. Enhancing air delivery speed is more related to the design and operation of the compressor rather than the function specifically of an aftercooler. Therefore, the primary purpose of aftercoolers is to condense moisture from compressed air, making the option of moisture condensation the most appropriate choice.