Fills
Cooling Tower Spares
Fills
Fill is what actually does the cooling in a tower. It increases water surface area and contact time with air. For wet cooling towers, there are 2 main types plus variations:
1. Film Fill
Water spreads into a thin film across vertical sheets. Maximum surface area, maximum efficiency.
Material: Usually PVC, sometimes ABS for high temp Types:
Cross-fluted: Sheets with angled corrugations. Most common. Good balance of performance vs fouling.
Vertical-fluted: Straighter channels. Lower pressure drop, better for dirty water.
Offset fluted: Higher efficiency, but clogs easier. Best for: Clean to moderately clean water, HVAC, power plants
Pros: Highest thermal performance, compact tower Cons: Clogs easily with debris, algae, scale. Needs good water quality. Max inlet temp ∼55°C for PVC Typical surface area: 150-250 m²/m³ of fill volume
2. Splash Fill
Water hits horizontal bars and breaks into droplets. Air flows around the drops. Material: PVC, PP, wood, or polypropylene grids Types:
Splash bars: Simple horizontal grids. Old school, very robust. Splash decks: Molded grids that create more droplet breakup Best for: Dirty water, refineries, steel mills, water with fibers/solids
Pros: Handles bad water, easy to clean, high temp tolerance up to 80°CCons: Needs 30-50% more volume than film fill for same duty. Higher pumping head. Typical surface area: 30-50 m²/m³ of fill volume3. Specialty / Hybrid Fill
3. Trickle fill
Combination of film and splash. Water trickles down surfaces and drips. Middle ground for moderate water quality. Ceramic/Concrete: Rare now. Use d for extremely high temp or fire resistance. Heavy and expensive.
Quick Selection Guide Water Quality Best Fill Temp Limit Clean, treated Film fill, cross-fluted55°C PVC, 80°C CPVC Moderate TSS, biological Low-fouling film55°C PVC Dirty, high TSS, fibers Splash fill80°C PP Seawater PP splash or CPVC film 80°CMaterial notes: PVC is standard and cheap. CPVC handles hotter water but costs 2-3x more. PP is best for chemicals and high temp, but lower structural strength. Running dirty water through film fill will clog it in months. Running clean water through splash fill means you built an oversized tower.
