ProTerra® Metal Fan with BI-FLOW® Shutter
ProTerra® Fiberglass Fan with BI-FLOW® Shutter	Idler tensioner provides smoother operation and maintains constant optimum belt tension.
BI-FLOW® Shutter Open	BI-FLOW® Shutter Closed
ProTerra® Fiberglass Fan with Louvers	ProTerra® Fiberglass Light Restricting Fan
ProTerra® Louver Shutter in Gray	ProTerra® Louver Shutter in White
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Video BI-FLOW® Shutter Video (1.74Mb)

ProTerra® Metal and Fiberglass Fans with BI-FLOW® Shutters

Click here for information about our 54-inch model!

Top Performance Enhanced with a High-Efficiency Shutter

BI-FLOW® Shutter improves fan performance by minimizing obstructions during fan operation.

• Delivers up to 10% more air with 75% less opportunity for air to leak through compared to a traditional louver shutter.
• BI-FLOW Doors do not suffer the 12-15% loss of efficiency and air speed typical of dirty louver-style shutters, so air speed is maintained over time.
• The BI-FLOW Shutter consists of only two moving parts for greater reliability and easier cleaning.

ProTerra® Fiberglass Fans with Louvers

One-Piece Cone Improves Air Flow up to 14%; Efficiency up to 21%.

ProTerra® Fiberglass Cone Fan Features

• Corrosion-resistant, reinforced-fiberglass housing with aluminum motor mounts and a heavy cast-aluminum blade.
• Backed by ProTerra® Systems’ generous extended warranty including limited lifetime coverage for housing and blade, and a bonus year on motors. (See ProTerra® Full Written Warranty for complete warranty details.)
• High CFM and CFM/watt, even under high static pressure.
• Heavy-duty, cast iron, air-handler type bearings are self-aligning, pre-lubricated, and include a zerk fitting, as well as being shielded from moisture and dust.
• Grill simply snaps into impact-resistant, polyethylene, one-piece cone with no fasteners required.

ProTerra® Metal Fans with Louvers

Performance, Features and Value.

ProTerra® Metal Cone Fan Features

• Factory-assembled using heavy-gauge, galvanized steel panels with screw fasteners in a slant-wall style.
• Smaller fans have galvanized steel blades, while the 52-inch (132.1-cm) model has blades made of even heavier gauge galvanized steel.
• Automatic belt tensioning system uses an idler arm and pulley to maintain constant optimum belt tension on the fan’s easy-to-change belt.
• Heavy-duty, cast iron, air-handler type bearings are self-aligning, pre-lubricated, and include a zerk fitting, as well as being shielded from moisture and dust.

ProTerra® Louver Shutter

Available in White or Gray

• Belled shutter has a curved, aerodynamic frame with flexible louver edges to help seal the fan’s opening.
• Corrosion-proof vinyl construction with a rigid vinyl frame and fiberglass rod hinges for the louvers.
• Louvers are easy to replace and have a smooth, easy-care finish for low maintenance.