Fan Filter Unit (FFU)

Fan Filter Unit (FFU) is a self-contained modular air purification terminal unit, the core air supply component of all local and full-room cleanroom systems. It integrates blower motor, primary pre-filter, high-efficiency HEPA filter and airflow equalization diffuser in one compact cabinet. FFU draws air from upper plenum, removes micro-particles, bacteria and contaminants through double-stage filtration, and discharges steady vertical laminar airflow downward to the working area. Multiple FFUs combined on ceiling grids can form full laminar flow ceilings; single or grouped units can be installed inside clean booths, laminar flow workbenches and sterile stations, flexibly creating Class 100~100,000 (ISO5~ISO8) dust-free environments without large central AHU renovation.

Main Structure & Material Breakdown

1. Outer Cabinet Housing

Three mainstream material options for different working conditions:

• Galvanized steel cabinet: Standard general type, electrostatic anti-rust coating, cost-effective for electronics, ordinary clean workshops

• Aluminum alloy cabinet: Lightweight, low vibration, good heat dissipation, low noise performance

• SUS304 / SUS316L stainless steel cabinet: For hospital OR, pharmaceutical sterile zones, labs with frequent alcohol/chlorine disinfection, anti-corrosion and easy wiping sterilization

  All cabinets adopt fully folded seamless forming, internal noise-absorbing cotton to reduce operation noise; bottom mounting frame matches universal cleanroom T-bar ceiling grid for fast suspended installation.

2. Blower & Motor Assembly (Core Power Part)

Two motor types for selection:

1. EC Energy-Saving Brushless Motor (Recommended Premium Model)

   External rotor centrifugal fan, stepless speed regulation, 30%~50% lower power consumption than traditional AC motors; support centralized group control via RS485 communication, remote speed adjustment, real-time operation status monitoring, ultra-low noise ≤50dB(A) at rated airflow, long service life ≥50,000 hours.

2. Multi-Speed AC Motor (Economical Model)

   3/5 speed adjustable mechanical control, simple circuit, low maintenance cost, suitable for small-scale clean booths and temporary production lines.

   Built-in airflow straightening guide vanes eliminate turbulent flow, guarantee even wind speed across filter outlet surface.

3. Double-Stage Filtration System

1. Primary Pre-filter (Top intake side)

   MERV5~MERV8 washable polypropylene fiber pre-filter, intercepts large dust to protect rear HEPA filter, extend HEPA service life, quick room-side replacement without lifting FFU down from ceiling.

2. HEPA Final Filter (Bottom outlet side)

   Mini-pleat ultra-fine glass fiber media, two sealing solutions:

   • EPDM rubber frame seal: For medium cleanliness ISO7~ISO8 clean zones

   • Gel trough gel-seal design: Zero air bypass leakage, for ISO5-Class100 high-standard sterile environments (pharmacy, operating room)

     Efficiency grades:

   • H13: ≥99.99% filtration efficiency for 0.3μm particles

   • H14: ≥99.995% filtration efficiency for 0.3μm particles (GMP/FDA cGMP mandatory standard)

     Optional ULPA U15~U19 filter for ultra-high purity semiconductor labs.

4. Air Equalization Diffuser Plate

Perforated aluminum alloy diffuser installed under HEPA filter, breaks concentrated airflow into evenly distributed vertical laminar flow, controls uniform wind speed 0.3~0.45m/s across entire working surface, eliminates airflow dead zones and vortexes inside clean space.

5. Control System Options

• Local single unit control: Knob stepless speed regulator / 3-speed manual switch

• Centralized group control: PLC touch screen + RS485 bus linkage, unified start/stop, speed grouping, filter clogging alarm, fault feedback

• Optional differential pressure monitoring port to track filter resistance change, remind scheduled filter replacement