This master should be used by designers working on Port of Portland construction projects and by designers working for PDX tenants (“Tenants”). Usage notes highlight a few specific editing choices, however the entire section should be evaluated and edited to fit specific project needs.

SECTION 233300 - AIR DUCT ACCESSORIES

PART 1 - GENERAL

1.1  DESCRIPTION

  1. This section describes medium and low pressure HVAC duct accessories, sealants and tapes, flexible connectors, combination fire/smoke dampers, access doors, spin-in fittings, extractors, drain pans, back draft dampers, and airflow measuring stations.

1.2  RELATED WORK SPECIFIED ELSEWHERE

  1. Section 230719, HVAC Insulation
  2. Section 230900, Instrumentation and Controls of HVAC Systems
  3. Section 233113, Low Pressure Ductwork
  4. Section 233114, Medium Pressure Ductwork

1.3  REFERENCES

  1. NFPA: National Fire Protection Association
  2. NFPA 90A: Standard for the Installation of Air-Conditioning and Ventilating Systems
  3. SMACNA: Sheet Metal and Air Conditioning Contractors' National Association, Inc.
  4. SMACNA HVAC Duct Construction Standards - Metal and Flexible

1.4  SUBMITTALS

  1. For systems, equipment, and components specified herein, submit product/material data; shop drawings; operation and maintenance data; as-constructed data; installation, startup, and testing manuals; operation and maintenance manuals; and as-constructed drawings.
  2. Include the manufacturer’s installation instructions.

Use only if Commissioning Section 019100 is included in the project manual.

  1. For systems, equipment, and components specified herein, submit commissioning plans and schedules; checkout, startup, operational, functional and final acceptance test plans, procedures, checklists, and reports; systems manuals; and operation and maintenance training plans.

1.5  QUALITY ASSURANCE

  1. Work shall be performed by qualified, experienced mechanics in accordance with SMACNA and these specifications.
  2. Install entire ductwork system, including materials and installation, in accordance with NFPA90A.
  3. Flexible connectors, flexible equipment connections, tapes and sealants shall be listed as UL 181, Class I air duct; flame spread rating shall not exceed 25 and smoke developed rating shall not exceed 50.

PART 2 - PRODUCTS

2.1  MEDIUM PRESSURE HVAC DUCT ACCESSORIES

  1. Acceptable Manufacturers: As indicated, or equal.
  2. Duct Sealer: Duro Dyne, EC900, S-2; 3M, United, or equal.
  3. Duct Tape: Duro Dyne, FT-2, Hardcast, Nashua, United; or equal.
  4. Tape and Adhesive/Activator System for Sheet Metal: Hardcast, or equal.
  5. Flexible Connector:
  6. Acceptable Manufacturers: Kinetics, Model KNM-100B, or equal.
  7. Description: One pound per square foot density, barium sulphate load vinyl material with fiberglass reinforcing.
  8. Access Doors:
  9. Acceptable Manufacturers: United Sheet Metal APR or ASR; Metco; Semco; Cesco; Ruskin; NailorHart, or equal.
  10. Description: Round, oval or rectangular to match duct, single wall to open against positive duct pressure, fastened with spring clips, pressure seal gasket, fastened with chain. Double wall access doors similar except provide insulated frame and insulated door.
  11. Bell Mouth Fittings: Round or flat oval, radius of 0.20 D minimum.

2.2  LOW PRESSURE HVAC DUCT ACCESSORIES

  1. Acceptable Manufacturers: As indicated, or equal.
  2. Damper Regulators:
  3. Ventlok model numbers used; similar products by Young or Durodyne are acceptable.
  4. Dial Regulator: Concealed or exposed duct in unfinished spaces, blade lengths 18-inch and less, 3/8-inch, Ventlock 635 or 638 for insulated duct. For blade lengths 19 inches and more, similar except 1/2-inch shafts.
  5. Dial Regulator: Exposed duct finished space, 3/8-inch, Ventlock 640.
  6. Dial Regulator: Concealed, not accessible, blade lengths 18-inch and less, 3/8-inch Ventlock 666 regulator with 680 mitered gear assembly where right angle turn is necessary. Blade lengths 19 inches and more, similar except 1/2-inch shafts.
  7. End Bearings: For ducts rated to 1-inch W.G., open end, Ventlock 607. For ducts rated above 1-inch W.G., closed end, Ventlock 609. Exposed ductwork, finished spaces, Ventlock 609. Spring end bearings will not be allowed.
  8. Volume Damper Fabrication:
  9. Single blade dampers shall be reinforced or crimped for rigidity, with pivot rod extending through duct. Dampers over 12 inches high shall use multiple opposed blade damper. Single blade damper shall be no larger than 12 inches by 48 inches. Multiple blade damper factory fabricated, Ruskin MD-35.
  10. Construct mnimum gauge and duct in accordance with SMACNA “HVAC Duct Construction Standards - Metal and Flexible.”
  11. Splitter and butterfly dampers shall be fabricated of 18-gauge galvanized steel.
  12. Dampers shall be of length suitable to close branch ducts without damper flutter.
  13. Damper blade shall be aligned with handle and index pointer.
  14. Flexible Equipment Connections: 30 oz. Ventfabrics Ventglas or Duro Dyne Durolon neoprene coated fire retardant glass fabric.
  15. Extractors (EX): Gang operated blades, steel construction, blades at 1-inch centers, slide operator set 15 degrees into main trunk duct. Titus AG-45 with No. 1 operator; Carnes; Anemostat; Barber-Coleman; Nailor-Hart.
  16. Spin-In Fittings:
  17. Sheet Metal Duct: Straight pattern sheet metal spin-in fitting designed for connection to sheet metal ductwork, volume damper, and locking quadrant. Construct with spot welds or rivets. Button-punch fabrication prohibited.
  18. Fiberglass Duct: Straight pattern sheet metal spin-in fitting designed for connection to fiberglass ductwork volume damper, and locking quadrant. Construct with spot welds or rivets. Button-punch fabrication prohibited.
  19. Duct Sealer: United; Duro Dyne, S-2; 3M, EC900; Atlas, Multi-Purpose.
  20. Duct Tape for Sheet Metal: ARNO, C520; United; Duro Dyne; Nashua.
  21. Tape and Adhesive/Activator System for Sheet Metal: Hardcast.
  22. Turning Vane Assemblies:
  23. Sheet Metal Vanes: Multiple radius hollow vane air foil type 2-inch (small vane) or 41/2-inch (large vane) inside radius, galvanized steel construction.
  24. Runners: Push-on type.
  25. Acoustical Vanes: Multiple radius air foil type, perforated steel construction with fiberglass fill. AirSan Acoustiturn.
  26. Access Doors:
  27. Acceptable Manufacturers: Air Balance; Ruskin; Metco; Durodyne; Cesco; Nailor-Hart.
  28. Doors shall be complete with steel frame, steel door with backing plate, cam latches (two on units 14-inch by 14-inch and larger), hinge and gasketing. Doors on insulated or lined ducts shall be insulated.
  29. Size:

Duct Width or Duct Diameter / Net Access Door Opening
Up to 8" / 6" x 6"
9" to 12" / 8" x 8"
13" to 20" / 12" x 12"
21" to 30" / 16" x 14"
31" to 42" / 18" x 14"
Over 42" / Two 16" x 14"
  1. Backdraft Dampers:
  2. Acceptable Manufacturers: Air Balance; Ruskin; Cesco; Advanced Air; Nailor-Hart.
  3. Description: Gravity operated, vinyl edged, metal bladed backdraft dampers.
  4. Drip Pans: Provide Type 304 stainless steel drip pans for cooling coils.
  5. Louver Blank-Off Panels: At air intake or exhaust louvers which are only partially active area, blank off inactive area with sheet metal closure panels caulked airtight, secured to louver frame and insulated with 2-inch rigid fiberglass insulation in accordance with Section 230719, HVAC Insulation.

2.3  COMBINATION FIRE/SMOKE DAMPERS

  1. Acceptable Manufacturers: Where Ruskin is the only manufacturer indicated, equivalent products by Air Balance, Inc.; Prefco; National Controlair; Nailor Hart; Safeair; or equal may be furnished.
  2. Combination Smoke and Fire Dampers (FSD): Multiblade damper with linkage, extended control rod, damper end switch and damper operator with 1-1/2 hour UL Fire Damper Label. Provide round or oval duct connections where required. Operator shall be factory-installed, electric type, 120V with spring return to closed position. Stall type motors are not acceptable. Ruskin Model FSD-36 or equal, for low pressure ductwork. Ruskin Models FSD-60 or FSDR-25 with airfoil shape blades for medium pressure ductwork.

2.4  AIR FLOW STATION (DUCT-MOUNTED AND FAN INLET)

  1. General: Electronic air measuring system consisting of thermistor based sensor probes and microprocessor based electronics.
  2. Acceptable Manufacturers: Ebtron, Duct-Mounted XP000 Series, Fan Inlet XF000 Series; Kurz; or pre-bid approved equal.
  3. SensorProbes: Thermistors probes and linear ICs, aluminum casing, duct-mounted, wiring Teflon or Kynar coated and encased, -20ºF to 160ºF operating range, weather resistant finish, flanged welded aluminum frame.
  4. Microprocessor and Electronics: Solid state microprocessor, permanent non-volatile memory, regulated power supply, software-based system. 0-5 vdc, 0-10 vdc, or 4-20 mA signals, linear flow and temperature outputs, line surge and transient protection.
  5. Performance: ±2 percent, +20 FPM across total calibrated range of 0 to 5000 FPM for ductmounted, 0-10,000 FPM for fan inlet-mounted, repeatability better than ±0.4 percent of reading. Pressure drop shall not exceed 0.005-inch W.G. at 2000 fpm.

2.5  AIRFLOW STATION (FAN INLET)

  1. Acceptable Manufacturers: Air Monitor VOLU-probe/FI; Paragon; Pace; or pre-bid approved equal.
  2. Fan inlet airflow traverse probe, multiple total and static pressure sensors placed at concentric area centers along exterior surface of cylindrical probe, internally connected to averaging manifolds.
  3. Dual end support swivel brackets suitable for mounting in fan inlet bell, aluminum construction, hard anodized finish.
  4. Probes shall be capable of producing steady, non-pulsating signals of standard total and static pressure, without need for flow corrections or factors with an accuracy of 3 percent of actual flow over a fan operating range of 6 to 1 capacity turndown.

PART 3 - EXECUTION

3.1  INSTALLATION

  1. Install all devices in accordance with the manufacturer’s recommendations.
  2. Install medium pressure duct accessories in accordance with Section 233114, Medium Pressure Ductwork.
  3. Install low pressure duct accessories in accordance with Section 233113, Low Pressure Ductwork.
  4. Combination Fire/Smoke Dampers:
  5. Install dampers in accordance with NFPA 90A and the manufacturer’s recommendations.
  6. Size and locate dampers as shown on the drawings.
  7. Where dampers are not accessible for servicing by removing an outlet, provide access doors for servicing. Doors shall be compatible with the duct in which they are installed.
  8. Access Doors: Install where indicated and at all automatic control dampers, fire dampers, and air flow stations to provide access for cleaning and maintenance.
  9. Back Draft Dampers: Install where indicated and at the discharge (or inlet) of exhaust fans where automatic dampers are not indicated.
  10. Automatic Dampers: Install in accordance with Section 230900, Instrumentation and Controls of HVAC Systems. Coordinate damper operators with Section 230900.
  11. Louver Blank-Off Panels: Install blank-off panels on unused portions of louvers.
  12. Airflow Station (Duct-Mounted): Install grid array in ductwork where indicated. Provide gasket between frame and duct. Mount electronic components in nearest temperature control panel. Install in accordance with the manufacturer’s instructions.
  13. Airflow Station (Fan Inlet): Install in fan inlet bell in accordance with the manufacturer’s instructions.

Choose one of the following two articles. Use Commissioning if Section 019100 is included in the project manual; otherwise use Testing.

3.2  commissioning

  1. Commission systems, equipment, and components specified herein.

3.3  TESTING

  1. Check out, start up, and test systems, equipment, and components specified herein.

END OF SECTION 233300

3/30/2016 / AIR DUCT ACCESSORIES
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