Section 15890 HVAC: DUCTWORK

Section 15890

HVAC: DUCTWORK

PART 1 - GENERAL

1.1 THE REQUIREMENT A. Section Includes:

1. HVAC ductwork and accessories

B. Related Specification Sections include but are not necessarily limited to:

1. Division 01, Additional General Requirements

2. Section 05150, Aluminum Construction

3. Section 09905, Architectural Paint Finishes

4. Section 11005, Equipment: Basic Requirements

5. Section 15970, Instrumentation and Control for HVAC Systems

1.2 QUALITY ASSURANCE

A. Referenced Standards:

1. Aluminum Association (AA):

45 Designation System for Aluminum Finishes.

2. American Architectural Manufacturers Association (AAMA):

2605 Voluntary Specification, Performance Requirements and Test Procedures for Superior Performing Organic Coatings on Aluminum Extrusions and Panels.

3. American Society of Heating, Refrigerating and Air Conditioning Engineers

(ASHRAE):

52 Method of Testing Air Conditioning Devices Used in

General Ventilation for Removing Particulate Matter.

4. ASTM International (ASTM):

B221 Standard Specification for Aluminum and Aluminum- Alloy Extruded Bars, Rods, Wire, Profiles, and Tubes

5. National Fire Protection Association (NFPA)

6. Sheet Metal and Air Conditioning Contractors' National Association (SMACNA): Ducted Electric Heat Guide for Air Handling Systems

HVAC Duct Construction Standards - Metal and Flexible

7. Underwriters Laboratory, Inc. (UL):

555 Standard for Safety Fire Damper and Ceiling Fire

Damper

555S Standard for Safety Leakage Rated Dampers for Use in

Smoke Control Systems

Building Materials Directory

8. Building Code:

a. International Code Council (ICC):

1) International Building Code and associated standards, 2009 Edition including all State of California 2010 amendments, referred to herein as California Building Code.

B. Qualifications:

1. Fabricator: Firms regularly engaged in the manufacture of the specific product, of type, size required, whose products have been in use in similar service for not less than three (3) years.

2. Installers: Firm with at least five (5) years installation experience on products similar to that required for this Project.

1.3 DEFINITIONS

A. Installer or Applicator:

1. Installer or applicator is the person actually installing or applying the product in the field at the Project site.

2. Installer and applicator are synonymous.

1.4 SUBMITTALS

A. Shop Drawings:

1. Submittals shall be made in accordance with the General Requirements, Additional General Requirements and as specified herein.

2. See Specification Section 11005, Equipment: Basic Requirements.

3. Efficiency ratings per ASHRAE 52 for factory built and assembled filter units.

4. Scaled ductwork drawings (1/4 inch equals 1 foot) showing duct and accessory layout and support.

B. Operation and Maintenance Manuals:

1. See Section 01783, Vendor Equipment Manuals, for requirements for:

a. The mechanics and administration of the submittal process. b. The content of Operation and Maintenance Manuals.

C. Miscellaneous Submittal:

1. Documentation of qualifications for fabricators and installers.

PART 2 - PRODUCTS

2.1 ACCEPTABLE MANUFACTURERS

A. Subject to compliance with the Contract Documents, the following manufacturers are acceptable:

1. Transverse joints (factory fabricated aluminum):

a. Ductmate Industries, Inc. b. Nexus.

c. Ward Industries, Inc. d. Or equal.

2. Flexible ducts:

a. Thermaflex. b. Condu-flex. c. Glass-flex. d. Or Equal.

3. Turning vanes:

a. Barber - Colman. b. Titus.

c. Tuttle and Bailey. d. Or Equal.

4. Flexible duct connections:

a. Vent Fabrics. b. Duro-Dyne.

c. Or Equal.

5. Flexible connector thrust restraint:

a. Mason WB. b. Kinetics

c. Or Equal.

6. Access doors in ductwork:

a. Vent Fabrics.

b. American Warming. c. Or Equal.

7. Backdraft dampers:

a. Air Balance. b. Ruskin.

c. American Warming. d. Or Equal.

8. Fire dampers:

a. Air Balance. b. Ruskin.

c. American Warming. d. Or Equal.

9. Ceiling diffusers: a. Anemostat. b. Carnes.

c. Titus.

d. Or Equal.

10. Grilles and registers:

a. Anemostat. b. Carnes.

c. Titus.

d. Or Equal.

11. Air filters:

a. American Air Filter. b. Farr.

c. Continental. d. Or Equal.

12. Manual (volume) dampers:

a. Air Balance. b. Ruskin.

c. American Warming. d. Or Equal.

13. Duct sealers:

a. Chicago Mastic. b. 3M Co.

c. Permatex.

d. Benjamin Foster. e. Or Equal.

14. Temperature control and automatic dampers:

a. Air Balance. b. Ruskin.

c. American Warming. d. Or Equal.

15. Pressure Relief Vents:

a. Retrotec. b. Draper.

c. Or Equal.

2.2 COMPONENTS

A. Duct and Fittings (Metallic):

1. Materials: 3003 H-14 aluminum alloy.

2. Fabrication:

a. Minimum sheet material thickness:

1) Ducts with Largest Side or Diameter to 30 Inches: 0.05 inch thick.

2) Ducts with Largest Side or Diameter Greater than 30 Inches: 0.08 inch thick.

b. Utilize SMACNA HVAC Duct Construction Standards for minimum of 2-inch water gauge static pressure for the minimum sheet material thickness specified herein.

1) Heavier gauge sheet material may be used with associated reinforcement as an alternate to minimum thickness specified.

2) Lighter gauge sheet material with associated reinforcement shall not be used as an alternate to minimum thickness specified.

c. Continuously weld seams on factory assembled units. d. Transverse joints (Alternate A):

1) SMACNA T-22 companion flange.

2) Gasketed.

3) Rigidity class:

a) Ducts with Largest Side or Diameter to 30 Inches: SMACNA Class

D (1-1/2 inches x 1-1/2 inches x 1/8 inch angles).

b) Ducts with Largest Side or Diameter Greater than 30 Inches to 54

Inches: SMACNA Class H (2-1/2 inches x 2-1/2 inches x 3/16 inch angles).

e. Transverse joints (Alternate B):

1) Materials and fabrication:

a) Angles: Aluminum. (1) Ductmate 35.

b) Corners: Aluminum.

(1) Ductmate DC 35.

c) Snap Cleats: Aluminized or stainless steel.

d) Gaskets: Closed cell neoprene.

e) Bolts: Stainless steel.

f) Sheet Metal Screws: Self-drilling stainless steel with unthreaded section under head.

2) Fabrication:

a) Rigidity Class: SMACNA Class H. b) 3/8 inch diameter x 1 inch bolts.

B. Supports and Hangers:

1. Materials:

a. Support Angles: Aluminum or stainless steel.

b. Hanger Rods: Stainless steel.

c. Anchors: Stainless steel wedge type.

2. Fabrication: Trapeze type units.

C. Turning Vanes:

1. Materials: Same as duct.

2. Fabrication:

a. Fabricate double vane units.

b. Pressure Drop through Elbows: Maximum 20 percent of velocity pressure. D. Flexible Duct Connections:

1. Materials: Hypalon, double coated closely woven glass fabric.

2. Fabrication: Withstand 4.5-inch water column, positive and negative pressure.

E. Access Doors:

1. Materials:

a. Inner Panel, Out Panel and Frame: Same as duct.

b. Gaskets: Closed cell neoprene.

c. Insulation: 1 pound density fiberglass.

d. Hinges: Stainless steel.

e. Latches:

1) Aluminum-zinc alloy.

2) Outside lever handle.

3) Adjustable spacer.

4) Beveled inside flange.

5) Studs:

a) Minimum 3/8 inch diameter stud for doors up to 24 inches wide x 48 inches high.

b) Minimum 1/2 inch diameter stud for doors larger than 24 inches x 48 inches.

2. Fabrication:

a. Provide four-side continuous gaskets. b. Utilize continuous piano hinges.

c. Latches required:

1) 12 Inches in any Direction: One (1).

2) Up to 18 Inches x 18 Inches: Two (2).

3) Up to 24 Inches x 48 Inches: Two (2) with inside handles.

4) Up to 24 Inches x 72 Inches: Three (3) with inside handles.

5) Minimum Door Size: 12 inches x 12 inches.

F. Flexible Duct:

1. Material: Continuous steel supporting spiral covered with 100 percent continuous filament fiberglass with nonporous fiberglass/vinyl liner and reinforced Mylar/neoprene outer cover.

2. UL listed, Class 1 with flame spread of 25 or less and smoke development rating not to exceed 50.

G. Drain Pan:

1. Materials: Aluminum.

2. Fabrication: 0.080 inch.

H. Backdraft Dampers:

1. Material:

a. 6063 T5 aluminum.

b. Blade Edge Seals: Extruded vinyl.

2. Fabrication:

a. Frame Thickness: 0.125 inch minimum.

b. Blade Thickness: 0.070 inch minimum.

c. Linkage: 1/2 inch tie bars.

d. Bearings: Synthetic.

I. Fire Dampers:

1. Materials:

a. Frame, Blades, Enclosure: Galvanized steel.

2. Fabrication:

a. Frame: 20 gauge, G60. b. Blades:

1) Curtain type

2) 24 gauge, G60

c. Enclosure: 20 gauge, G60.

d. Fusible Link: 212 degrees F, UL listed.

e. Fire Rating: 1-1/2 hours per UL 555.

f. Mounting: Vertical or horizontal.

g. Design with blade package out of air stream.

J. Diffusers SD-1:

1. Materials:

a. Body: Extruded aluminum.

b. Ceiling Diffuser Gaskets: Sponge rubber.

2. Fabrication:

a. Type: Square or rectangular with removable core.

b. Key operated opposed blade damper mounted in neck except where indicated on Drawings to be omitted.

1) Dampers to be housed in round to square adapters. c. Finish:

1) Diffusers: Clear satin anodized.

2) Interior of Supply Diffusers: Flat black paint.

K. Volume Dampers and Flow Equalizers for Round Neck Diffusers:

1. Material: Aluminum.

2. Fabrication:

a. Design for Neck Velocity: Maximum 2500 feet/minute.

b. Center rod operator accessible through diffuser without removing diffuser.

c. Furnish with screws, duct collars, transitions and air pattern deflectors as required.

L. Air Grille and Register Assembly:

1. Materials:

a. Assembly: Extruded aluminum.

b. Gaskets: Sponge rubber.

2. Fabrication:

a. Supply Registers (SR-1): Two (2) sets individually adjustable louvers.

b. Exhaust and Return Registers (RR-1, RG-1): 45-degree deflection front blades.

c. Dampers in SR-1 and RR-1: Key-operated opposed blade.

d. Screws, duct collars, and transitions as required.

e. Finish for Units Installed in Finish Areas W here Ductwork is Concealed: Prime painted with primer compatible with paint specified in Specification Section

09905, Architectural Paint Finishes.

M. Roof-Mounted Gravity Relief Hood:

1. Materials:

a. Hood: Aluminum.

b. Screen: Expanded aluminum.

2. Fabrication:

a. Type indicated on Drawings. b. 0.080 inch thick material.

c. Insulated.

d. 85 percent free area bird screen.

e. Design to withstand 100 mph winds. f. Capacity as scheduled.

N. Air Filters:

1. Materials:

a. Holding Frame: Aluminum.

2. Fabrication:

a. Factory built and assembled unit.

b. Efficiency rating as per ASHRAE 52. c. 2-inch thickness minimum.

d. Efficiency: 20 percent.

e. Air Velocity: 450 FPM maximum.

f. Clean Pressure Drop: 0.2 inch WG maximum.

g. Size, Capacity, and Type: As indicated on Drawings.

O. Temperature Control, Automatic and Manually (Volume) Operated Dampers:

1. Material:

a. Body: 6063 T5 aluminum.

b. Seal Blade Edge: Extruded vinyl.

2. Fabrication:

a. Frame Thickness: 0.125 inch minimum. b. Blades:

1) Two-Position Damper: Parallel blade.

2) Mixing and Volume Damper: Opposed blade.

3) Airfoil shape.

4) Maximum 6-inch width.

c. Linkage: Concealed in frame.

d. Axles: 1/2 inch plated steel hex.

e. Bearings: Molded synthetic.

f. Seals:

1) Jamb: Flexible compression type.

g. Control Shaft: Removable, 1/2 inch diameter.

h. Air Leakage (4-Foot Square Damper) at 4 Inches WG Pressure: 99 cfm maximum.

i. Motors for Motor Operated Damper: See Specification Section 11005, Equipment: Basic Requirements.

j. Provide outboard support for operator linkage where damper motor is to be installed outside of duct.

k. Provide stainless steel locking quadrants for manual (volume) dampers.

l. Provide fold out operator mounting bracket where damper motor is to be installed on face of damper or inside duct.

m. Finish: 215 R1 anodized. P. Pressure Relief Vents:

1. Material: Galvanized steel.

2. Weather louver

3. Single-Flow (relieve in a single direction)

4. Wall sleeve.

5. Fixing kit and labels.

6. Retrotec Model “RSH”, Draper Model “High-X”, Or Equal.

7. Schedule:

a. Battery Room: 488 sq. in. venting area. b. Control Room: 1870 sq. in. venting area.

c. Switchgear and Electrical Rooms: 3297 sq. in. venting area.

8. See Architectural schedules for size and shape.

2.3 MAINTENANCE MATERIALS A. Extra Materials:

1. Furnish OCSD with the following extra materials:

a. Twelve complete filter media changes for each filter unit.

b. Filter media used during construction is in addition to this requirement and at no additional cost to OCSD.

PART 3 - EXECUTION

3.1 INSTALLATION

A. See Specification Section 11005, Equipment: Basic Requirements. B. Metal Ductwork:

1. Install with longitudinal seams sealed for zero leakage.

a. Welded seams may be used upon acceptance of welded seam samples by

ENGINEER.

2. Install gaskets at each transverse joint and fasten sections together with bolts. a. Tighten for zero leakage.

3. Install supports and hangers with anchors in accordance with SMACNA HVAC Duct Construction Standards.

4. Install turning vanes in square elbows:

a. Unsupported vane length not to exceed 48 inches.

b. Position vanes at proper angle to meet specified pressure drop

5. Install flexible connections at fans:

a. Locate as close as possible to fan.

b. Allow 1 inch of slack to prevent vibration transmission. c. Install thrust restraints across connectors.

6. Install access doors where indicated on Drawings and at fire dampers in accordance with NFPA requirements.

C. Flexible Ductwork:

1. Install in Concealed Areas Between: Low velocity ductwork and diffusers, return air grilles or exhaust outlets and ducts.

2. Use low loss fittings for connection to duct.

3. Connect to metal duct collars by means of non-combustible synthetic rubber sealing compound and stainless steel drawband.

D. Drain Pans:

1. Install at fan coil cooling coils, control valves above finished ceilings and at other sources of moisture.

2. Install metal tubing at drain and terminate above floor drain, equipment drain and as shown on Drawings.

E. Dampers:

1. Install where indicated on Drawings of sizes shown.

2. Install fire dampers in ductwork passing through 1 hour or higher fire-rated construction.

a. Install in wall and floor openings utilizing steel sleeves, angles and other materials following practices required to provide installation in accordance with local Building Codes.

F. Diffusers:

1. Install where shown on Drawings of size and capacities scheduled on Drawings.

2. Install painted lay-in type in lay-in ceilings.

3. Install prime painted diffusers in areas where ductwork is concealed.

4. Install anodized diffusers in exposed ductwork. G. Air Grille and Register Assemblies:

1. Install where shown on Drawings of size and capacities scheduled on Drawings.

2. Install prime painted grilles and registers in areas where ductwork is concealed. a. Field paint to match adjacent surface finish.

H. Air Filters:

1. Install where shown on Drawings of size and capacity scheduled on Drawings.

2. Do not operate equipment during construction without filters.