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Spun steel exhaust fans shall be centrifugal belt driven type. Fan wheel shall be centrifugal backward
inclined type. The wheel shall be constructed of steel and coated with a non-stick coating similar to Teflon®
as manufactured by Du Pont®. Wheel shall include a wheel cone carefully matched to the inlet cone for
precise running tolerances. Wheels shall be statically and dynamically balanced.
The fan housing shall be constructed of 16 gauge galvaneal steel with a rigid internal support structure and
shall be leakproof. The fan housing shall be constructed with a one piece windband with an integral rolled
bead for added strength and shall be joined to the curb cap with a continuously welded seam.
Fan’s windband shall have a clean out port, a 4-inch diameter hole on the outside of the fan’s windband
with a grease repellent compression rubber fit, allowing access to entire wheel for cleaning.
Motors shall be heavy duty ball bearing type, carefully matched to the fan load, and furnished at the
specified voltage, phase and enclosure. Drive frame assembly shall be constructed of heavy gauge
galvanized steel. Motors and drives shall be mounted on heavy duty true vibration isolators, out of the
airstream. Fresh air for motor cooling shall be drawn into the motor compartment through a ten square inch
tube free of discharge contaminants. Motors and drives shall be readily accessible for maintenance.
Precision ground and polished 1-inch minimum diameter fan shafts shall be mounted in cast pillow block
lubricatable ball bearings. Bearings shall be selected for a minimum L10 life in excess of 100,000 hours
(L50 average life of 500,000 hours) at maximum cataloged operating speed. Dual drives shall be sized for a
minimum of 150% of driven horsepower. Pulleys shall be of the cast type, keyed and securely attached to
the wheel and motor shafts.
Motor pulleys shall be adjustable for final system balancing. All fans shall have a dual belt and pulley
system. A NEMA-3R disconnect switch shall be factory installed and wired from the fan motor to a junction
box installed outside the motor compartment.
All fans shall bear the AMCA Certified Ratings Seal
for sound and air performance.
Each fan shall bear a permanently affixed
manufacturer’s engraved metal nameplate containing
the model number and individual serial number for
future identification.
Fans shall be Listed by Underwriters Laboratory for
UL/cUL 762 Listed for all electrical components and
grease removal.
Hinge kit shall be constructed of heavy gauge
hinges and shall include hold open cables for field
installation.
Grease trap shall include the drain connection. The
unit shall collect grease and water from the fan and
extract the grease from the water for ease of grease
disposal.
Fans shall be model USGF as manufactured by
Greenheck Fan Corporation in Schofield, Wisconsin.
Specifications