If the inlet filter is dirty or moist, what action is required?

• A. Wipe with towel
• B. Ignore and continue
• C. Replace filter
• D. Rinse with water

Answer: (C)

Keep the inlet filtration clean and dry because it protects the system from particulates and moisture that can cause damage or decreased performance. When the inlet filter is dirty or wet, it can’t reliably trap contaminants or maintain proper airflow, and moisture can promote microbial growth and filter collapse. Replacing the filter is the correct action because new media restores the designed filtration rating, ensures a proper seal, and prevents contaminated air from entering. Wiping, rinsing, or ignoring won’t restore performance: wiping may push dirt around, rinsing introduces more moisture and doesn’t guarantee removal of all particulates, and ignoring the issue risks system damage.