Speciﬁcations, Direct Drive, GB Belt Drive

Speciﬁcations

Centrifugal Downblast Roof Exhaust Fans

H-G — Direct Drive

Model H-G spun aluminum exhaust fans shall be centrifugal direct driven type. The fan wheel shall be centrifugal backward inclined, constructed of aluminum and 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 drawn from high strength aluminum and connected to a heavy gauge steel internal frame with integral bracing and a birdscreen.

Motors shall be heavy duty ball bearing type, carefully matched to the fan load, and furnished mounted to the steel drive assembly at the specified voltage, phase, and enclosure. Motors or drive assembly shall be mounted on vibration isolators. Fresh air for motor cooling shall be drawn into the motor compartment through a large space between the fan shroud and motor cover. Motors shall be readily accessible for maintenance.

A disconnect shall be NEMA rated and factory installed with wiring included from the fan motor to a junction box installed within the motor compartment. A conduit chase shall be provided through the base to the motor compartment for ease of electrical wiring.

All fans shall bear the AMCA Certified Ratings Seal for sound and air performance.

Each fan shall bear a permanently affixed manufacturer’s engraved nameplate constructed of aluminum and containing the model number and individual serial number for future identification.

Fans shall meet all Greenheck wind load standards and shall contain the following third party certifications.

•Licensed P.E. calculations shall be available for fan per ASCE 7-02 Minimum Design Loads for Buildings and Other Structures for exposure class C, 60 foot building height, and a type II building.

•Fan shall be tested in accordance with ASTM E330-02. Structural Performance of Exterior Windows, Doors, Skylights, and Curtain Walls by Uniform Static Air Pressure Difference at the ASCE 7-02 calculated design load.

•Licensed P.E. calculations for attachment of fan to curb shall be available for ASCE 7-02 determined design pressure.

•All calculations and testing shall be done by a state licensed P.E., and a certified test lab.

Fans shall be Greenheck model H-G manufactured by Greenheck Fan Corporation in Schofield Wisconsin.

H-GB — Belt Drive

Model H-GB spun aluminum exhaust fans shall be centrifugal belt driven type. The fan wheel shall be centrifugal backward inclined, constructed of aluminum and 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 drawn from high strength aluminum and connected to a heavy gauge steel internal frame with integral bracing and a birdscreen.

Motors shall be heavy-duty ball bearing type, carefully matched to the fan load, and furnished mounted to the steel drive frame at the speciﬁ ed voltage, phase, and enclosure. Drive frame assembly shall be constructed of heavy gauge steel with engineered forms for added strength. Motors and drives shall be mounted on vibration isolators with no metal to metal contact, out of the airstream. Fresh air for motor cooling shall be drawn into the motor compartment through a large space between the fan shroud and the motor cover. Motors and drives shall be readily accessible for maintenance.

Precision ground and polished fan shafts shall be mounted in pillow block ball bearings. Bearings shall be selected for a minimum (L10) life in excess of 100,000 hours (L50 average of 500,000 hrs) at maximum cataloged operating speed. 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 ﬁ nal system balancing. A disconnect switch shall be NEMA rated and factory installed with wiring included from the fan motor to a junction box installed within the motor compartment. A conduit chase shall be provided through the base to the motor compartment for ease of electrical wiring.

All fans shall bear the AMCA Certified Ratings Seal for sound and air performance.

Each fan shall bear a permanently afﬁ xed manufacturer’s engraved metal nameplate containing the model number and individual serial number for future identiﬁ cation.

Fans shall meet all Greenheck wind load standards and shall contain the following third party certiﬁ cations.

•Licensed P.E. calculations shall be available for fan per ASCE 7-02 Minimum Design Loads for Buildings and Other Structures for exposure class C, 60 foot building height, and a type II building.

•Fan shall be tested in accordance with ASTM E330-02. Structural Performance of Exterior Windows, Doors, Skylights and Curtain Walls by Uniform Static Air Pressure Difference at the ASCE 7-02 calculated design pressure.

•Licensed P.E. calculations for attachment of fan to curb shall be available for ASCE 7-02 determined design pressure.

•All calculations and testing shall be done by a state licensed P.E., and a certiﬁ ed test lab.

Fans shall be Greenheck models H-GB and H-GB-HP, manufactured by Greenheck Fan Corporation in Schoﬁ eld, Wisconsin.