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OC Sportsplex Pool HVAC Unit Replacement <br />PDC Project 23022 HVAC Ducts and Casings 23 31 00 - 5 <br />unless otherwise specified. <br />2.Manufacturer of engineered connector system must have certified independent performance <br />testing for leakage,deflection and seismic stability. <br />3.All components of the engineered system must be clearly embossed with the manufacturer’s <br />name,model number or identifying marking. <br />4.Butyl rubber gasket must be applied per the manufacturer’s instructions on all connections <br />except for breakaway connections.Closed Cell Neoprene gasket must be applied per the <br />manufacturer’s instructions on all breakaway connections.No substitution of connector <br />system components or gaskets is permitted. <br />5.All duct installed using engineered connectors must adhere to the manufacturer’s published <br />assembly and installation guidelines for all standard,breakaway,roof-top or specialty <br />connections unless otherwise specified. <br />B.Formed-on Flanges: <br />1.Lockformers TDC or Engles TDF may be used in accordance with T-25 flanges of SMACNA <br />HVAC Duct Construction Standards,provided that corner pieces with bolts are used. If <br />TDF/TDC flanges are damaged,replace the damaged joint(s)by straightening and reinforcing <br />with minimum 1-1/2 x 1-1/2 x 1/4 angle at each side of transverse joint <br />PART 3 EXECUTION <br />3.01 INSTALLATION <br />A.Install,support,and seal ducts in accordance with SMACNA (DCS). <br />B.During construction provide temporary closures of metal or taped polyethylene on open ductwork <br />to prevent construction dust from entering ductwork system. <br />C.Install ductwork parallel to building walls and ceilings and at such heights not to obstruct any <br />portion of window,doorway,stairway,or passageway. Install ductwork to allow adequate access <br />and service space for equipment and access clearances for cable tray/j-hooks.Refer to drawings <br />and/or manufacturer's recommendations Install vertical ductwork plumb. Make allowances for <br />beams,pipes or other obstructions in building construction and for work of other contractors. <br /> Check plans showing work of other trades and consult with Engineer in event of any interference. <br />D.Where interferences develop in the field,offset or reroute ductwork as required to clear such <br />interferences. Do not divide duct and do not route any other utilities such as piping or conduit <br />through duct. In all cases,consult drawings for exact location of space allocated for duct,ceiling <br />heights,door and window openings,or other architectural details before fabricating or installing <br />duct. Consult Designer where conflicts arise between ductwork and other utilities which cannot be <br />resolved by relocating duct. <br />E.Where offsets in ductwork are required,contractor to use standard 30,45 or 90-degree elbows. <br /> Where space constraints do not allow for the use of standard elbows for offsets,use of angled <br />offsets as depicted by SMACNA Figure 2-7 (Angled Offset Type 1)may be used with maximum <br />angle of offset not to exceed 15 degrees maximum.Offsets Type 2 and 3 in SMACNA Figure 2-7 <br />shall not be allowed. <br />F.Rectangular Duct Elbows: <br />1.Rectangular Duct:Unless specific type is indicated,provide radius elbows with splitter vanes <br />with minimum centerline radius to width or diameter ratio of 1.5 <br />a.1.5 radius elbows with full spliter vanes as follows: <br />1)One vane for duct width 2-12" <br />2)Two vanes for duct width 13-20" <br />3)Three vanes for duct width 21"-36" <br />4)Four vanes for duct width 38"and larger <br />5)Fabricate vanes in accordance with SMACNA. <br />b.Rectangular throad elbows with turning vanes where 1.5 radius elbows do not fit. <br />c.Rectangular throat/radius heel elbows or rectangular elbows without turning vanes shall <br />not be used. <br />G.Round and Oval Duct Elbows: <br />Docusign Envelope ID: D4F3B98E-0756-4A0C-A3AD-05AA32D39F1C