Primary Pre-Filters‌

Primary pre-filters serve as the first line of defense in air purification systems, primarily capturing large particles ≥5μm (such as dust, pollen, and hair) to protect downstream medium- and high-efficiency filters, extending their lifespan. Their core functions include:

• ‌Coarse Filtration‌: Made from materials like non-woven fabric, nylon mesh, or metal mesh, with filtration efficiency of 30%-90% (for 5μm particles).
• ‌System Protection‌: Reduces load on medium/high-efficiency filters, lowering maintenance costs.

‌Types & Structure‌

1. ‌By Filtration Grade‌
   • ‌G1-G4‌: European standard EN779 classification, with G4 achieving 70%-90% efficiency (5μm).
2. ‌By Filter Material‌
   • ‌Reusable‌: Metal mesh or nylon mesh (e.g., aluminum-frame pre-filters).
   • ‌Disposable‌: Non-woven fabric or synthetic fiber (e.g., flat panel pre-filters).
3. ‌By Design‌
   • ‌Flat Panel‌: Low cost, suitable for HVAC systems.
   • ‌Pleated‌: Larger filtration area, higher dust holding capacity.
   • ‌Pocket‌: Higher efficiency, ideal for pre-filtration stages.

‌Key Parameters & Selection‌

‌Installation & Maintenance‌

1. ‌Installation Notes‌
   • Match system airflow (recommended velocity: 1-3 m/s).
   • Check sealing (e.g., double-lip seal design).
2. ‌Maintenance Schedule‌
   • Commercial spaces: 3-6 months; industrial: 1-3 months.
   • Replacement criteria: Pressure drop reaches 2-3× initial resistance or visible dust accumulation.

‌Typical Applications‌

• ‌HVAC Systems‌: Pre-filtration for downstream protection.
• ‌Cleanrooms‌: Air return filtration or pre-stage for HEPA filters.
• ‌Industrial‌: Air compressor or gas turbine intake pre-filtration.