Construction:
Housing
The fan shall be constructed of heavy gauge powder coated steel for aesthetics. Fan scroll
and discharge duct shall be continuously welded to prevent grease leakage. Fan shall include
integral hinges at the base to allow the fan to swing away for easy cleaning of the duct in
compliance with NFPA-96. Hinges shall be designed to limit the amount of travel, preventing
damage to the fan or roof. The hinged section of the fan shall be provided with heavy gauge,
oversized handles welded in place to allow safe, fast and easy opening.
Base
The base shall be constructed of heavy gauge powder coated steel with pre-punched mounting
holes for fasteners. Base corners shall be welded to provide strength and support for
hinging and cleaning and to prevent leakage into the building.
Wheel
The fan wheel shall be centrifugal backward inclined and non-overloading. Wheels shall be
balanced in two planes and done in accordance with AMCA standard 204-96, Balance Quality
and Vibration Levels for Fans. The wheel blades shall be aerodynamically designed to minimize
turbulence, increase efficiency and reduce noise. The wheel shall be heavy gauge welded steel.
In the event that balancing weights are required they shall be riveted or welded to the blades
or wheel. The wheel inlet shall overlap the fan base inlet for maximum performance and
efficiency. The wheel shall be firmly attached to the motor shaft with set screws.
Motor & Motor Compartment
Motors shall be heavy duty ball bearing type, mounted out of the airstream and furnished at
the specified voltage, phase and enclosure. Motor mounting plate shall be constructed of heavy
gauge steel and isolated from the fan structure with vibration isolators. The motor compartment
shall be cooled by outside air drawn through louvers in the motor cover. The motor compartment
shall be of a two-piece construction with the top cap being completely removable to provide
unobstructed access to the motor and drives. The fan shall have a tilt open top cover assembly
that allows the wheel to be tilted back for easy access during cleaning and maintenance. The
tilt open top cover assembly shall have latch locks to secure the assembly to the housing.
Shaft and Bearings
Shafts shall be precision ground and polished. Heavy duty, per-lubricated bearings shall be
selected for a minimum life (L50) life in excess of 200,000 hours of operation at cataloged
operating speed. They shall be designed and individually tested specifically for use in air
handling applications.
Belts & Drives
Belts shall be oil and heat resistant, non-static type. Drives shall be cast type, precision
machined and keyed and secured attached to the fan and motor shafts. Drives shall be sized
for a minimum of 150% of the installed motor horsepower. Fan operating speed shall be factory
set using adjustable pitch motor pulleys.
Grease Spout
The grease drain is fully welded and centered in the discharge scoop, a removable grease
trough is attached to the scoop to collect grease.
Safety Disconnect Switch
A safety disconnect switch shall be standard on all CBRE units with open drip proof motors.
Switches shall be installed in a NEMA3R enclosure and mounted to exterior of the fan for
easy access.
Product: Fan shall be model CBRE as manufactured by CaptiveAire Systems.
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