SECTION 23 33 00
AIR DUCT ACCESSORIES
PART 1 GENERAL
1.01 DESCRIPTION OF WORK
A. Extent of ductwork accessories work is indicated on Drawings and in Schedules, and by requirements of this Section.
B. Types of ductwork accessories required for project include the following:
1. Dampers: a. Low pressure manual dampers. 2. Fire dampers. 3. Duct take-off fittings. 4. Turning vanes. 5. Duct hardware. 6. Duct access doors. 7. Flexible connections.
C. Refer to Section 23 05 93 for Testing, Adjusting, and Balancing of ductwork accessories; not work of this Section.
1.02 QUALITY ASSURANCE
A. Codes and Standards:
1. SMACNA Compliance: Comply with applicable portions of SMACNA "HVAC Duct Construction Standards, Metal and Flexible". 2. Industry Standards: Comply with ASHRAE recommendations pertaining to construction of ductwork accessories, except as otherwise indicated. 3. UL Compliance: Construct, test, and label fire dampers in accordance with UL Standard 555 "Fire Dampers and Ceiling Dampers". 4. NFPA Compliance: Comply with applicable provisions of NFPA 90A "Air Conditioning and Ventilating Systems", pertaining to installation of ductwork accessories.
1.03 SUBMITTALS
A. Comply with Section 01 33 23, Submittals.
B. Product Data: Submit manufacturer's technical product data for each type of ductwork accessory, including dimensions, capacities, and materials of construction; and installation instructions.
C. Maintenance Data: Submit manufacturer's maintenance data including parts lists for each type of duct accessory. Include this data, product data, and shop drawings in maintenance manual, in accordance with requirements of Division 1.
COPYRIGHT LEWIS, ELLIOTT, MCMORRAN, Air Duct Accessories – 23 33 00 VADEN, RAGSDALE & WOODWARD, INC. 2021 Page 1 of 4 PART 2 PRODUCTS
2.01 DAMPERS
A. Low Pressure Manual Dampers: Provide dampers of single blade type or multi blade type, constructed in accordance with SMACNA "HVAC Duct Construction Standards".
1. Round dampers, unless integral to duct takeoff, shall be equal to Ruskin MDRS25, 20 ga. galvanized steel, 3/8" square axle shaft and molded synthetic bearings. 2. Rectangular dampers shall be equal to Ruskin MD25, 22 ga. galvanized steel 3/8" square axle shaft and molded synthetic bearings. 3. Provide lever handle operator with locking nut and mounting plate shown "OPEN" and "CLOSED" positions. Lever handle shall indicate damper position between open and closed. Lever handle shall be provided with a stand-off bracket to extend lever above external insulation where applicable. Shop fabricated dampers are not acceptable
B. Available Manufacturers: Ruskin Mfg. Co., Greenheck, or acceptable qual.
2.02 FIRE DAMPERS
A. Fire Dampers: Provide fire dampers, of types and sizes indicated. Construct casings of galvanized steel with mill galvanized finish. Fire dampers shall be manufactured and installed in accordance with NFPA Pamphlet No. 90A. Fire dampers shall be mounted in sleeves of gauges and lengths recommended by the manufacturer to meet NFPA mounting requirements. Provide damper with positive lock in closed position, and with the following additional features:
1. Damper Blade Assembly: Curtain type. 2. Blade Material: Steel, match casing.
B. Low velocity fire dampers: Ruskin D-IBD2 Style 'B' Dynamic type with blades removed from air stream for square and rectangular duct, D-1BD2 Style CR fire damper for round ductwork or IBDT2 for grille installation. All dampers shall have integral sleeve IBD and picture frame mounting angles and shall be UL listed for the application for which it is installed. Static dampers may be used when unit is interlocked to shut down with duct smoke detector and installed in vertical position. Dampers shall be UL rated for 1½ hours in walls rated less than 3 hours and rated 3 hours in walls rated 3 hours or more.
C. Available Manufacturers: Ruskin Mfg. Co., Greenheck, or acceptable equal.
2.03 DUCT TAKE-OFF FITTINGS A. Round supply take-off fittings shall be 45° transi fitting equal to Flexmaster Model STD with 1" wide mounting flange and adhesive coated gasket, damper, 3/8” square axle shaft, nylon bearings, quadrant indicator and 2" standoff bracket. Return and exhaust fittings shall be air-track gasketed type. All flanged/adhesive fittings shall be attached with sheet metal screws at 4" spacing around circumference of flange.
2.04 TURNING VANES
A. Fabricated Turning Vanes: Provide fabricated turning vanes and vane runners, constructed in accordance with SMACNA "HVAC Duct Construction Standards".
COPYRIGHT LEWIS, ELLIOTT, MCMORRAN, Air Duct Accessories – 23 33 00 VADEN, RAGSDALE & WOODWARD, INC. 2021 Page 2 of 4 B. Manufactured Turning Vanes: Provide turning vanes constructed of 1 1/2" wide curved blades set at 3/4" o.c., supported with bars perpendicular to blades set at 2" o.c., and set into side strips suitable for mounting in ductwork.
C. Available Manufacturers: Environmental Elements Corp., Subs. Koppers Co., Inc., or acceptable equal.
2.05 DUCT HARDWARE
A. Provide duct hardware, manufactured by one manufacturer for all items on project, for the following:
1. Test Holes: Provide in ductwork at fan inlet and outlet, and elsewhere as indicated, duct test holes, consisting of slot and cover, for instrument tests. 2. Quadrant Locks: Provide for each damper, quadrant lock device on one end of shaft; and end bearing plate on other end of damper lengths over 12". Provide extended quadrant locks and end extended bearing plates for externally insulated ductwork.
B. Available Manufacturers: Ventfabrics, Inc., Young Regulator Co., or acceptable equal.
2.06 DUCT ACCESS DOORS
A. Provide duct access doors minimum of 18" x 18" where required to repair or replace controls, fusible links, etc. Provide minimum size except where duct dimensions are too small for this size, then door shall be 2” less than duct dimension. Round duct doors may be 10” x 6” galvanized steel oval door with plastic securing knobs and gasket.
B. Construction: Construct of same or greater gauge as ductwork served, provide insulated doors for insulated ductwork. Provide flush frames for uninsulated ductwork, extended frames for externally insulated duct. Provide one size hinged, other side with one handle type latch for doors 12" high and smaller, 2 handle type latches for larger doors.
C. Available Manufacturers: Ruskin Mfg. Co., or acceptable equal.
2.07 FLEXIBLE CONNECTIONS
A. Provide flexible duct connections wherever ductwork connects to vibration isolated equipment. Construct flexible connections of neoprene coated flameproof fabric crimped into duct flanges for attachment to duct and equipment. Make airtight joint. Provide adequate joint flexibility to allow for thermal, axial, transverse, and torsional movement, and also capable of absorbing vibrations for connected equipment. Insulate flexible connector with duct wrap insulation. See Section 23 07 00.
B. Available Manufacturers: Ventfabrics, Inc., or acceptable equal.
PART 3 EXECUTION
3.01 INSPECTION
A. Examine areas and conditions under which ductwork accessories will be installed. Do not proceed with work until unsatisfactory conditions have been corrected.
COPYRIGHT LEWIS, ELLIOTT, MCMORRAN, Air Duct Accessories – 23 33 00 VADEN, RAGSDALE & WOODWARD, INC. 2021 Page 3 of 4 3.02 INSTALLATION OF DUCTWORK ACCESSORIES
A. Install ductwork accessories in accordance with manufacturer's installation instructions, with applicable portions of details of construction as shown in SMACNA standards, and in accordance with recognized industry practices to ensure that products serve intended function.
B. Fire dampers and sleeves shall not be attached directly to floors and walls, but shall be held in place by steel mounting angles on each side of wall. Mounting angles shall be attached to damper sleeves and not to wall. Sleeves and mounting angles shall be designed and installed to remain in place even if duct collapses. Dampers shall be installed per the Manufacturer's installation instructions complying with Underwriters Laboratories Safety Standard 555.
C. Install turning vanes at any change of direction in supply as well as return ducts. Radius elbows may be used in lieu of turning vanes for ducts less than 36” in width. Where sharp throat elbows are constructed, a single turning vane shall be installed adjacent to the throat.
D. Install access doors to open against system air pressure, with latches operable from either side, except outside only where duct is too small for person to enter.
E. Coordinate with other work, including ductwork, as necessary to interface installation of ductwork accessories properly with other work.
3.03 FIELD QUALITY CONTROL
A. Operate installed ductwork accessories to demonstrate compliance with requirements. Test for all leakage while system is operating. Repair or replace faulty accessories, as required to obtain proper operation and leak proof performance.
3.04 ADJUSTING AND CLEANING
A. Adjusting: Adjust ductwork accessories for proper settings, install fusible links in fire dampers and adjust for proper action.
1. Label access doors in accordance with Section 23 05 53, Mechanical Identification. 2. Final positioning of manual dampers is specified in Section 23 05 93, Testing, Adjusting, and Balancing.
B. Cleaning: Clean factory finished surfaces. Repair any marred or scratched surfaces with manufacturer's touch up paint.
3.05 EXTRA STOCK
A. Furnish extra fusible links to Owner, one link for every 10 installed of each temperature range.
END OF SECTION
COPYRIGHT LEWIS, ELLIOTT, MCMORRAN, Air Duct Accessories – 23 33 00 VADEN, RAGSDALE & WOODWARD, INC. 2021 Page 4 of 4