Which statement describes when an air purge should be performed?

• A. After every use to clear the line.
• B. Before charging a new or relocated line to ensure a steady stream.
• C. Only when there is visible air bubbles at the nozzle.
• D. During nighttime maintenance.

Answer: (B)

Purging air before charging a line is done to remove trapped air so the line fills evenly and produces a steady, uninterrupted stream. When a new or relocated line is installed, air pockets can remain along the length; if you charge with these pockets, you’ll get inconsistent flow, sputtering, or pressure fluctuations. By using a purge process, you vent the air out until a smooth flow of liquid emerges, indicating the line is free of air and ready for normal operation. Purging after every use isn’t necessary and wastes time, waiting for visible bubbles is reactive and can leave air in the system, and nighttime maintenance isn’t related to the actual charging step. So the correct practice is to purge before charging a new or relocated line to ensure a steady stream.