... impeller 3. Plastic fan 556x167 fan blade for 5HP heat pump water heater,22' fan Outer Diameter: 556mmHeight:167mmShaft hole ... axial flow fan blade products, with low noise, large air volume, anti-vibration, good balance effect, the pressure ... material, durability and other characteristics, it is air conditioner, air energy heatpump water heater, exhaust ventilation equipment, refrigerators/fridge and ...