Why Dust on Filters Matters
When the primary filter of an air-handling unit (AHU) collects dust, air resistance rises and fan efficiency drops. Scale on the heat exchanger increases thermal resistance and, over time, corrodes pipes until they leak. Scale in the water-spray system clogs nozzles and hurts heat exchange.
Filter Types and Easier Upkeep
Primary filters use metal mesh, ceramic rings, glass fiber, coarse foam or synthetic fiber in a frame; non-woven fabric is now common. They need manual cleaning, so a traveling roll filter โ whose medium self-cleans in an oil bath โ reduces labor. A simple maintenance kit with an extra solution tank or acid-proof pump is cheap to add.
Cleaning Method
- Most primary filters are removable; rinse with plain water.
- For oily dust, water alone fails โ use a detergent wash (Dichen).
- Wet the filter, let it dry, spray the solution, wait 3โ5 minutes, then rinse until clean.
Common Mistake
Operators sometimes skip maintenance or even remove the filter, letting dust settle on coil fins and sharply cutting cooling and airflow. Regular cleaning keeps the unit within design conditions.