PERFORMANCE REQUIREMENTS Fan Performance Ratings: [Project site elevation- based] [Sea level elevation-based]. Electrical Components, Devices, and Accessories: Listed and labeled as defined in NFPA 70. CENTRIFUGAL ROOF VENTILATORS Description: Belt- Driven, filtered supply, centrifugal roof ventilators, for flow of clean air for Heating, Ventilating, and Air-Conditioning (HVAC) applications. Basis of Design Product: Twin City Fan & Blower, Model LPSF. Permanently attach nameplate displaying serial number and unit information. Fan Capacities, Characteristics, and Configuration: Refer to Drawing schedule. Specifier: Select steel option in following paragraph for all cases except spark-resistant construction. Fan Wheel: Double width, double inlet fan wheels, constructed of galvanized steel, backward inclined, single thickness blades, continuously welded into rim and back plate. Statically and dynamically balance wheel. Fan Shaft: AISI 1040 or 1045 hot rolled steel, accurately turned, ground, polished, and ring gauged. Apply petroleum based rust prevention coating. Bearings: Manufacturer's standard field-lubricated ball or roller bearings, based on fan size. Minimum L-50 Bearing Life: 200,000 hours at maximum operating speed, in accordance with ABMA 9 for ball bearings, or ABMA 11 for roller bearings. Louvered Penthouse: Provide louvered penthouse ventilator enclosure. Units through size 32 ship assembled and size 36 is shipped knocked down to 38 feet of deck space. Unit sizes 21 and larger require contract haul. Fabricate unit of extruded aluminum louvers on welded aluminum structural frame, and reinforced, pitched, removable, aluminum hood. Fabricate unit top cover of 0.050 inch [1.3 mm] aluminum, with cross-break and reinforcement. Miter cut corners and continuously weld seams. Fabricate unit louvers of 0.081 inch [2.1 mm] aluminum. Provide internal reinforcement and bracing. Fabricate unit base of 0.080 inch [2.0 mm] aluminum. Provide louvered, top-hinged side access panel to allow entry without removing top hood. Specifier: The standard filter is removable, washable aluminum wire mesh. An optional filter is throw-away fiberglass. Filters: Provide [2 inch (51 mm) thick aluminum mesh removable, washable] [fiberglass filters, and rigid support rack. Belt Drives:
PERFORMANCE REQUIREMENTS Fan Performance Ratings: [Project site elevation- based] [Sea level elevation-based]. Electrical Components, Devices, and Accessories: Listed and labeled as defined in NFPA 70. CENTRIFUGAL ROOF VENTILATORS Description: Belt- Driven, filtered supply, centrifugal roof ventilators, for flow of clean air for Heating, Ventilating, and Air-Conditioning (HVAC) applications. Basis of Design Product: Twin City Fan & Blower, Model LPSF. Permanently attach nameplate displaying serial number and unit information. Fan Capacities, Characteristics, and Configuration: Refer to Drawing schedule. Specifier: Select steel option in following paragraph for all cases except spark-resistant construction. Fan Wheel: Double width, double inlet fan wheels, constructed of galvanized steel, backward inclined, single thickness blades, continuously welded into rim and back plate. Statically and dynamically balance wheel. Fan Shaft: AISI 1040 or 1045 hot rolled steel, accurately turned, ground, polished, and ring gauged. Apply petroleum based rust prevention coating. Bearings: Manufacturer's standard field-lubricated ball or roller bearings, based on fan size. Minimum L-50 Bearing Life: 200,000 hours at maximum operating speed, in accordance with ABMA 9 for ball bearings, or ABMA 11 for roller bearings. Louvered Penthouse: Provide louvered penthouse ventilator enclosure. Units through size 32 ship assembled and size 36 is shipped knocked down to 38 feet of deck space. Unit sizes 21 and larger require contract haul. Fabricate unit of extruded aluminum louvers on welded aluminum structural frame, and reinforced, pitched, removable, aluminum hood. Fabricate unit top cover of 0.050 inch [1.3 mm] aluminum, with cross-break and reinforcement. Miter cut corners and continuously weld seams. Fabricate unit louvers of 0.081 inch [2.1 mm] aluminum. Provide internal reinforcement and bracing. Fabricate unit base of 0.080 inch [2.0 mm] aluminum. Provide louvered, top-hinged side access panel to allow entry without removing top hood. Specifier: The standard filter is removable, washable aluminum wire mesh. An optional filter is throw-away fiberglass. Filters: Provide [2 inch (51 mm) thick aluminum mesh removable, washable] [fiberglass filters, and rigid support rack. Belt Drives: