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HomeMy WebLinkAbout23 34 16 Centrifugal HVAC FansBEARDSLEY DESIGN ASSOCIATES CORNELL – NCP CENTRIFUGAL HVAC FANS STANDARD SPECIFICATIONS 23 34 16 – PAGE 1 OF 5 MARCH 29, 2013 SECTION 233416 -- CENTRIFUGAL HVAC FANS PART 1 GENERAL 1.1 SUBMITTALS A. Product Data: Provide the following: 1. Include rated capacities, furnished specialties, and accessories for each fan. 2. Certified fan performance curves with system operating conditions indicated. 3. Certified fan sound-power ratings. 4. Motor ratings and electrical characteristics, plus motor and electrical accessories. 5. Material thickness and finishes, including color charts. 6. Dampers, including housings, linkages, and operators. 7. Vibration Isolators 8. Operation and Maintenance Data: For centrifugal fans to include in emergency, operation, and maintenance manuals. PART 2 PRODUCTS 2.1 PERFORMANCE REQUIREMENTS A. AMCA Compliance: 1. Comply with AMCA performance requirements and bear the AMCA- Certified Ratings Seal. 2. Operating Limits: Classify according to AMCA 99. B. Electrical Components, Devices, and Accessories: Listed and labeled as defined in NFPA 70, by a qualified testing agency, and marked for intended location and application. 2.2 INLINE CENTRIFUGAL FANS (BELT DRIVE) A. Basis-of-Design Product: Subject to compliance with requirements, provide Loren Cook Model SQI or a comparable product by one of the following: 1. Chicago Blower Corporation. 2. Cincinnati Fan. 3. New York Blower Company (The). B. Description: 1. Factory-fabricated, -assembled, -tested, and -finished, belt-driven centrifugal fans consisting of housing, wheel, fan shaft, bearings, motor, drive assembly, and support structure. 2. Deliver fans as factory-assembled units, to the extent allowable by shipping limitations. 3. Factory-installed and -wired disconnect switch. C. Disconnect Switches: BEARDSLEY DESIGN ASSOCIATES CORNELL – NCP CENTRIFUGAL HVAC FANS STANDARD SPECIFICATIONS 23 34 16 – PAGE 2 OF 5 MARCH 29, 2013 1. NEMA rated: 1 2. Positive electrical shut-off. D. Housings: 1. Formed panels to make curved-scroll housings with shaped cutoff. 2. Panel Bracing: Steel angle- or channel-iron member supports for mounting and supporting fan scroll, wheel, motor, and accessories. 3. Horizontally split, bolted-flange housing. 4. Spun inlet cone with flange. 5. Outlet flange. 6. Constructed of steel and coated with permatector. 7. Housing and bearing supports shall be constructed of welded steel members to prevent vibration and to rigidly support the shaft and bearing assembly balancing up to a minimum of 10 horsepower. E. Housing Supports and Drive Frame: 1. Housing supports are constructed of structural steel with formed flanges. 2. Drive frame is welded steel which supports the shaft and bearings and reinforcement for the housing. 3. Pivoting motor plate with adjusting screws to make belt tensioning operations. 4. Prepunched mounting holes for installation. 5. Drive frame is coated with Permatector. F. Backward-Inclined Wheels: 1. Non-overloading, backward inclined centrifugal wheel. 2. Constructed of aluminum. 3. Single-width-single-inlet construction with curved inlet flange, backplate, and fastened to shaft with set screws. 4. Welded or riveted to flange and backplate; cast-iron or cast-steel hub riveted to backplate. 5. Statically and dynamically balanced. 6. The wheel cone and fan inlet will be matched and shall have precise running tolerances for maximum performance and operating efficiency. G. Grease-Lubricated Shaft Bearings: 1. Self-aligning, pillow-block-type, tapered roller bearings with double- locking collars and two-piece, cast-iron housing. 2. Ball-Bearing Rating Life: L50 at 200,000 hours. H. Belt Drives: 1. Factory mounted, with adjustable alignment and belt tensioning. 2. Fan Pulleys: Cast iron or cast steel with split, tapered bushing; dynamically balanced at factory. Keyed and securely attached to wheel and motor shafts. 3. Motor Pulleys: Adjustable pitch for use with motors through 5 hp; fixed pitch for use with larger motors. Select pulley so pitch adjustment is at the middle of adjustment range at fan design conditions. 4. Belts: Oil resistant, nonsparking, and nonstatic; matched sets for multiple belt drives. 5. Readily accessible for maintenance. BEARDSLEY DESIGN ASSOCIATES CORNELL – NCP CENTRIFUGAL HVAC FANS STANDARD SPECIFICATIONS 23 34 16 – PAGE 3 OF 5 MARCH 29, 2013 6. Belt Guards: Fabricate to comply with OSHA and SMACNA requirements of diamond-mesh wire screen welded to steel angle frame or equivalent, prime coated. Secure to fan or fan supports without short circuiting vibration isolation. Include provisions for adjustment of belt tension, lubrication, and use of tachometer with guard in place. 7. Motor Mount: Adjustable for belt tensioning. I. Motors: 1. Motor enclosures: Open dripoff. 2. Motors are permanently lubricated, sealed, heavy duty ball bearing type furnished at the specific voltage, phase, and enclosure. J. Accessories: 1. Access for Inspection, Cleaning, and Maintenance: Comply with requirements in ASHRAE 62.1. 2. Companion Flanges: Rolled flanges for duct connections of same material as housing. 3. Galvanized frames with prepunched mounting holes. 4. Integral backdraft dampers. 5. Balanced for minimal resistance to flow. 6. Inlet Screens: For non ducted fans; grid screen of same material as housing. 7. Vibration isolators. 2.3 INLINE CENTRIFUGAL FANS (DIRECT DRIVE) A. Basis-of-Design Product: Subject to compliance with requirements, provide Loren Cook Model SQI or a comparable product by one of the following: 1. Chicago Blower Corporation. 2. Cincinnati Fan. 3. New York Blower Company (The). B. Description: 1. Factory-fabricated, -assembled, -tested, and -finished, direct-driven centrifugal fans consisting of housing, wheel, fan shaft, bearings, motor, drive assembly, and support structure. 2. Deliver fans as factory-assembled units, to the extent allowable by shipping limitations. 3. Factory-installed and -wired disconnect switch. C. Disconnect Switches: 1. NEMA rated: 1 2. Positive electrical shut-off. D. Housings: 1. Formed panels to make curved-scroll housings with shaped cutoff. 2. Panel Bracing: Steel angle- or channel-iron member supports for mounting and supporting fan scroll, wheel, motor, and accessories. 3. Horizontally split, bolted-flange housing. 4. Spun inlet cone with flange. BEARDSLEY DESIGN ASSOCIATES CORNELL – NCP CENTRIFUGAL HVAC FANS STANDARD SPECIFICATIONS 23 34 16 – PAGE 4 OF 5 MARCH 29, 2013 5. Outlet flange. 6. Constructed of steel and coated with permatector. 7. Housing and bearing supports shall be constructed of welded steel members to prevent vibration and to rigidly support the shaft and bearing assembly balancing up to a minimum of 10 horsepower. E. Housing Supports and Drive Frame: 1. Housing supports are constructed of structural steel with formed flanges. 2. Drive frame is welded steel which supports the shaft and bearings and reinforcement for the housing. 3. Prepunched mounting holes for installation. 4. Drive frame is coated with Permatector. F. Backward-Inclined Wheels: 1. Non-overloading, backward inclined centrifugal wheel. 2. Constructed of aluminum. 3. Single-width-single-inlet construction with curved inlet flange, backplate, and fastened to shaft with set screws. 4. Welded or riveted to flange and backplate; cast-iron or cast-steel hub riveted to backplate. 5. Statically and dynamically balanced. 6. The wheel cone and fan inlet will be matched and shall have precise running tolerances for maximum performance and operating efficiency. G. Motors: 1. Motors are permanently lubricated, sealed, heavy duty ball bearing type furnished at the specific voltage, phase, and enclosure. H. Accessories: 1. Access for Inspection, Cleaning, and Maintenance: Comply with requirements in ASHRAE 62.1. 2. Companion Flanges: Rolled flanges for duct connections of same material as housing. 3. Galvanized frames with prepunched mounting holes. 4. Integral backdraft dampers. 5. Balanced for minimal resistance to flow. 6. Inlet Screens: For non ducted fans; grid screen of same material as housing. 7. Vibration isolators. 8. Provide variable speed controller. PART 3 EXECUTION 3.1 INSTALLATION A. Install centrifugal fans level and plumb. B. Disassemble and reassemble units, as required for moving to the final location, according to manufacturer's written instructions. BEARDSLEY DESIGN ASSOCIATES CORNELL – NCP CENTRIFUGAL HVAC FANS STANDARD SPECIFICATIONS 23 34 16 – PAGE 5 OF 5 MARCH 29, 2013 C. Lift and support units with manufacturer's designated lifting or supporting points. D. Equipment Mounting: Install continuous-thread hanger rods and spring vibration hangers with vertical-limit stop of size required to support weight of centrifugal fans. E. Install units with clearances for service and maintenance. 3.2 FIELD QUALITY CONTROL A. Testing Agency: Engage a qualified testing agency to perform tests and inspections. B. Manufacturer's Field Service: Engage a factory-authorized service representative to test and inspect components, assemblies, and equipment installations, including connections. C. Perform the following tests and inspections[ with the assistance of a factory- authorized service representative]: 1. Verify that shipping, blocking, and bracing are removed. 2. Verify that unit is secure on mountings and supporting devices and that connections to ducts and electrical components are complete. Verify that proper thermal-overload protection is installed in motors, starters, and disconnect switches. 3. Verify that cleaning and adjusting are complete. 4. Disconnect fan drive from motor, verify proper motor rotation direction, and verify fan wheel free rotation and smooth bearing operation. Reconnect fan drive system, align and adjust belts, and install belt guards. 5. Adjust belt tension. 6. Adjust damper linkages for proper damper operation. 7. Verify lubrication for bearings and other moving parts. 8. Verify that manual and automatic volume control and fire and smoke dampers in connected ductwork systems are in fully open position. 9. See Division 23 Section "Testing, Adjusting, and Balancing For HVAC" for testing, adjusting, and balancing procedures. 10. Remove and replace malfunctioning units and retest as specified above. D. Prepare test and inspection reports. END OF SECTION 23 34 16