ATT_02a_Division_23_HVAC.pdf

1 Division 23 - HVAC

DIVISION 23 – HVAC

SECTION 23000- GENERAL

PART 1 – GENERAL

A. General Design:

1. Building Design and Load Calculations shall be calculated by qualified engineering personnel, with a minimum of 5 years’ experience with similar project types.

a. Load calculations shall be submitted prior to starting construction.

b. A complete system design must be submitted prior to starting construction. The system design will indicated the equipment data, supply and return duct locations and all register locations and sizes.

c. Design must meet all ASHRAE 90.1 and latest IBC Energy Code requirements.

2. Individual offices shall have the means for individual zone control with an independent thermostat and zone damper as basis of design.

a. Zones shall be limited to no more than 6 zone dampers per WSHP or

Blower coils.

3. All supply and return ducts and plenums will be insulated with a minimum of

R-6 insulation where located in conditioned spaces and a minimum of R-8 insulation where located outside the building thermal envelope. Where located within a building envelope assembly, the duct or plenum will be separated from the building exterior or unconditioned or exempt spaces by a minimum of R-8 insulation.

4. Duct liner board is not an acceptable material for any ducts; supply or return ducts.

5. Use ASHRAE 90 guidelines for energy use baseline.

6. Use ASHRAE 62 guidelines for minimum Indoor Air Quality.

7. Flush Out: Operate new system(s) with 100 percent outside air for a minimum duration of two weeks before occupancy of the building. Provide new filtration.

8. Permanent system filtration will be MERV 13 minimum.

PART 2 - PRODUCTS (Not applicable)

PART 3 – EXECUTION (Not Applicable)

End of Section- 23000

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SECTION 23080- HVAC COMMISSIONING

A. Contractor to provide a Commissioning Plan. The Commissioning Plan will outline the organization, scheduling, team members, and documentation pertaining to the overall commissioning process.

B. Contractor to provide a Functional Performance Test as part of the Commissioning

Plan, to include all aspects of the HVAC and mechanical systems. Commissioning is to be performed on-site, except where deemed feasible through the Basewide

Automation system.

C. Team is to include a minimum of the following team members:

1. DPW Project Manager

2. DPW Inspection Branch

3. DPW Energy Team

4. Base Servicing Agent

5. Installation Contractor

D. The subcontractor will be responsible for performing procedure presented in the specification and contract drawings, as detailed in the contractor’s Function

Performance Test (FPT). Members of the designated Commissioning Team will witness various portions of the commissioning process. The Commissioning Team members will sign off on appropriate sections after verifying installation, operation, or documentation.

E. Any test ports, gauges, test equipment, etc., needed to accomplish the FPT shall be provided by the Subcontractors.

F. Subcontractors will provide to the Commissioning Team documentation of calibration of controls. Documentation will include dates, setpoints, calibration coefficients, control loop verification, and other data required to verify the system check-out.

G. The subcontractor and associated manufacturer’s representatives shall provide required training to operational staff after the system description meetings have occurred. The Subcontractor training sessions shall provide a more detailed analogy of systems operation and maintenance.

PART 2 - PRODUCTS (Not applicable)

PART 3 – EXECUTION (Not Applicable)

End of Section- 23080

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SECTION 23100- HVAC INSTRUMENTATION AND CONTROLS

PART 1 - GENERAL

A. Summary:

1. This Section includes control equipment for HVAC systems and components, including control components for terminal heating and cooling units not supplied with factory-wired controls.

B. Related Sections:

1. Related Sections include the following:

a. Division 13, Section “Fire Alarm Systems”.

b. Division 26, Section “Basic Electrical Materials and Methods”.

C. Definitions:

1. DDC: Direct-digital controls.

2. LAN: Local area network.

3. MS/TP: Master-slave/token-passing.

4. PICS: Protocol Implementation Conformance Statement.

D. System Description:

1. Control system consist of sensors, indicators, actuators, final control elements, interface equipment, other apparatus and accessories to control mechanical systems.

E. Quality Assurance:

1. Installer Qualifications: An experienced installer a minimum 5 years’ experience with successful projects of similar scope, and who is a certified installer of the automatic control system manufacturer for both installation and maintenance of units required for this Project.

2. Manufacturer Qualifications: A firm experienced in manufacturing automatic temperature-control systems similar to those indicated for this Project and with a record of successful in-service performance.

3. Electrical Components, Devices, and Accessories: Listed and labeled as defined in NFPA 70, Article 100, by a testing agency acceptable to AHJ, and marked for intended use.

4. Comply with NFPA 90, “Installation of Air Conditioning and Ventilation

Systems”.

5. Comply with ASHRAE 135 for DDC system control components.

F. Coordination:

1. Coordinate locations of thermostats and other exposed control sensors with plans and room details before installation.

2. Coordinate equipment with Division 13, Section “Fire Alarm Systems”, to achieve compatibility with equipment that interfaces with that system.

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Section 23100- HVAC Instrumentation and Controls Cont.

3. Coordinate supply of conditioned electrical circuits for control units and operator workstation.

4. Coordinate equipment with Division 26, Section “Panelboards”, to achieve compatibility with starter coils and annunciation devices.

G. General Requirements:

1. Contractor will comply with Ft. Knox Template Six controls specification.

2. Large spaces being served with multiple pieces of equipment will be controlled as an area via the automation system.

3. Individual office shall have independent zone controls via thermostat and air control dampers unless deemed otherwise.

4. Mechanical and Pump rooms shall be controlled via automation system to provide lead/lag control, variable pumping speed control, seasonal change-over, setback as necessary and other energy savings strategies.

5. Temperature Setting will comply with Basewide standards and will be capable of Night Setback or Night Setup and implement Optimal Start/Stop.

H. Building Automation System:

1. Basis-of-Design- Trane Tracer SC Building Level Controls. Available manufacturers are subject to compliance with requirements.

2. All controls will be tied into DPW Basewide automation network unless excluded in the Project.

3. Tie-In to DPW Basewide automation system should be done via fiber optic when feasible.

4. All exhaust and ventilation fans (restrooms, kitchens, etc.) will be tied into building alarm system and will have an automatic shut-off and will be tied into the Basewide automation system.

PART 2 - PRODUCTS

A. Field Level Networks:

1. Available Manufacturers: Subject to compliance with requirements, manufacturers offering products that may be incorporated into the Work include, but are not limited to, the following:

a. Basis-of-Design- Trance Tracer UC Field Level Controls. Available manufacturers are subject to compliance with requirements.

b. Wireless controls should be Basis-of-Design on new controls networks unless otherwise deemed not economically feasible by the DPW Project

Manager.

B. Wireless Radios and Network Equipment:

1. Basewide fiber optic shall be 12 strand, single mode fiber for Main Basewide loop and 6 strand for building drops.

2. Network Switch:

c. Cisco- catalyst Compact 2960C-8TC-8

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3. Fiber Media Converters:

a. Blackbox LHC036A-R2

4. When determined that it is not feasible to use fiber optic, the following wireless radio will be used:

a. Ubiquity Nanobeam M2

b. Model: pbe-m2-400

PART 3 – EXECUTION

A. Examination:

1. Verify that conditioned power supply is available to control units and operator workstation.

2. Verify that duct, pipe, and equipment-mounted devices and wiring are installed before proceeding with installation.

B. Installation:

1. Install equipment level and plumb.

2. Install software in control units and operator workstation. Implement all features of programs to specified requirements and as appropriate to sequence of operation.

3. Connect and configure equipment and software to achieve sequence of operation specified.

4. Verify location of thermostats and other exposed control sensors with requirements and room details before installation. Locate all 60 inches above finished floor.

a. Install averaging elements in ducts and plenums in crossing or zigzag pattern.

5. Install guards on thermostats in the following locations:

c. Entrances.

d. Public Areas.

e. Where indicated.

6. Install automatic dampers in accordance with Division 23, Section “Duct

Accessories”.

7. Install labels and nameplates to identify control components in accordance with

Division 22, Section “Mechanical Identification”.

8. Install duct volume-control dampers according to Division 23, Section “Metal

Ducts”.

9. Verify installation of electronic and fiber-optic cables according to Division 26, Section “Control/Signal Transmission Media”.

10. Install electronic and fiber-optic cables according to Division 26, Section

“Control/Signal Transmission Media”.

C. Electrical Wiring and Connection Installation:

1. Install raceways, boxes, and cabinets in accordance with Division 26, Section

“Raceways and Boxes”.

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2. Install building wire and cable according to Division 26, Section “Conductors and Cables”.

3. Install signal and communication cable according to Division 26, Section

“Control/Signal Transmission Media”.

a. Conceal cable, except in mechanical rooms and areas where no other conduit and piping are exposed.

b. Install exposed cable in raceway or conduit.

c. Bundle and harness multiconductor instrument cable in place of single cables where several cables follow common path.

d. Fasten flexible conductors, bridging cabinets and doors along hinge side;

protect against abrasion. Tie and support conductors.

e. Number-code or color-code conductors for future identification and service of control system, except local individual room control cables.

4. Connect manual-reset limit controls independent of manual-control switch positions. Automatic duct heater resets may be connected in interlock circuit of power controllers.

5. Connect hand-off-auto selector switches to override automatic interlock controls where switch is in hand position.

D. Connections:

1. Ground Equipment.

f. Tighten electrical connections and terminals according to manufacturer’s published torque-tightening values. If manufacture’s torque values are not indicated, use those specified in UL 486A and UL 486B.

E. Field Quality Control:

1. Manufacturer’s Field Service: engage a factory- authorized service representative inspect field assembled components and equipment installation, including electrical connections. Report results in writing.

a. Operational Test: After electrical circuitry has been energized, start units to confirm proper unit operation. Remove malfunctioning units, replace with new units, and retest

b. Test and adjust controls and safeties. Replace damaged and malfunctioning controls and equipment, and retest.

c. Calibration test electronic controllers by disconnecting input sensors and stimulating operation with compatible signal generator.

2. Engage a factory-authorized service representative to perform startup.

3. Replace damaged or malfunction controls and equipment.

a. Start, test, and adjust control systems.

b. Demonstrate compliance with requirements, including calibration and testing, and control sequences.

c. Adjust, calibrate, and fine tune circuits and equipment to achieve sequence operation specified.

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4. Verify DDC as follows:

a. Verify software, including automatic reset, control sequences, scheduling, reset controls, and occupied/unoccupied cycles.

b. Verify operation of operator workstation.

c. Verify local control units, including self-diagnostics.

End of Section- 23100

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SECTION 23815 – METAL DUCTS

A. Summary:

1. This Section includes metal ducts for supply, return, outside, and exhaust air distribution systems in pressure classes from 2 inch to 10 inch wg. Metal ducts include the following:

a. Rectangular ducts and fittings.

b. Single-wall, round spiral-seam ducts and formed fittings.

B. Related Sections:

1. Related Sections include the following:

a. Division 23, Section “Duct Accessories”.

C. System Description:

1. System design, as indicated, has been used to select size and type of air-moving and distribution equipment and other air system components. Changes to system or configuration must be specifically approved by ESD PM. Accompany requests for layout modifications with calculations showing that proposed system will provide original design results without increasing system total pressure.

D. Quality Assurance:

1. Comply with NFPA 90A, “Installation of Air Conditioning and Ventilation

Systems”, and NFPA 90B, “Installation of Warm Air Heating and Air

Conditioning Systems”.

2. System filtration will be MERV 13 minimum.

PART 2 – PRODUCTS

A. Sheet Metal Materials:

1. Comply with SMACNA’s “HVAC Duct Construction Standards- Metal and

Flexible”, for acceptable materials, material thickness, and duct construction methods, unless otherwise indicated. Sheet metal materials will be free of pitting, seam marks, roller marks, stains, discolorations, and other imperfections.

2. Galvanized Sheet Steel: Lock-forming quality; complying with ASTM A 652/A

653M, and having G90 coating designation; ducts will have mill-phosphatized finish for surfaces exposed to view.

3. Carbon-Steel Sheets: ASTM A 366/A 366M

4. Reinforced Shapes and Plates: Galvanized-steel reinforcement where installed on galvanized sheet metal ducts; compatible materials for aluminum and stainless-steel ducts.

5. Tie Rods: Galvanized steel; 1/4 inch minimum diameter for lengths 36 inches or less, 3/8 inch minimum diameter for lengths longer than 36 inches.

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Section 23815- Metal Ducts Cont.

B. Sealant Materials::

1. Joint and Seam Sealants, General: The term “sealant” is not limited to materials of adhesive or mastic nature but includes tapes and combinations of open-weave fabric strips and mastics.

2. Water-Based Joint and Seam Sealant: Flexible, adhesive sealant, resistant to UV light when cured, UL 723 listed, and complying with NFPA requirements for

Class 1 ducts.

3. Solvent-Based Joint and Seam Sealant: One-part, nonsag, solvent-released-curing, polymerized butyl sealant formulated with a minimum of 75 percent solids.

C. Hangers and Supports:

1. Building attachments: Structural-steel fasteners appropriate for construction materials to which hangers are being attached.

2. Hanger Materials: Galvanized sheet-metal or threaded steel rod.

a. Strap and rod sizes: Comply with SMACNA’s “HVAC Duct Construction

Standards- Metal and Flexible” for steel sheet width and thickness and for steel rod diameters.

3. Duct Attachments: Sheet metal screws, blind rivets, or self-tapping metal screws compatible with duct materials.

4. Trapeze and Riser Supports: Steel shapes complying with ASTM A 36/A 36M.

a. Supports for Galvanized-Steel Ducts: Galvanized-steel shapes and plates.

D. Rectangular Duct Fabrication:

1. Fabricate ducts, elbows, transitions, offsets, branch connections, and other construction according to SMACNA’s “HVAC Duct Construction Standards-

Metal and Flexible” and complying with requirements for metal thickness, reinforcing types and intervals, tie-rod applications, and joint types and intervals.

a. Lengths: Fabricate rectangular ducts in lengths appropriate to reinforcement and rigidity class required for pressure class.

b. Deflection: Duct systems will not exceed deflection limits according to

SMACNA’s “HVAC Duct Construction Standards- Metal and Flexible”

2. Transverse Joints: Prefabricated slide-on joints and components constructed using manufacturer’s guidelines for material thickness, reinforcement size and spacing, and joint reinforcement.

3. Formed-On Flanges: Construct according to SMACNA’s “HVAC Duct

Construction Standards- Metal and Flexible”, Figure 1-4, using corner, bolt, cleat, and gasket details.

a. Duct Size: Maximum 30 inches wide up to 2 inch wg pressure class

b. Longitudinal Seams: Pittsburgh lock sealed with noncuring polymer sealant.

4. Cross Breaking or Cross Beading: Cross break or cross bead duct sides 19 inches and larger and 0.0359 inch thick or less, with more than 10 sq. ft. of nonbraced panel area unless ducts are lines.

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E. Round Duct and Fitting Fabrication:

1. Round, Longitudinal and Spiral Lock-Seam Ducts: Fabricate supply ducts of galvanized steel according to SMACNA’s “HVAC Duct Construction Standards-

Metal and Flexible”

2. Duct Joints:

a. Ducts up to 20 inches in Diameter: Interior, center-beaded slip coupling, sealed before and after fastening, attached with sheet metal screws.

b. Round Ducts: Prefabricated connection system consisting of double-lipped, EPDM rubber gasket. Manufacture ducts according to connection system manufacturer’s tolerances.

3. Fabricate elbows using die-formed, gored, pleated, or mitered construction.

Bending radius of die-formed, gored, and pleated elbows will be 1-1/2 times duct diameter. Unless elbow construction type is indicated, fabricate elbows as follows:

a. Mitered-elbow Radius and Number of Pieces: Welded construction complying with SMACNA’s “HVAC Duct Construction Standards- Metal and flexible”, unless otherwise indicated.

b. Round Mitered elbows: Welded construction with the following metal thickness for pressure classes from minus 2 inch to plus 2 inch wg:

1. Ducts 3 to 36 inches in diameter: 0.034 inch.

A. Duct Applications:

1. Static-Pressure Classes: Unless otherwise indicated, construct ducts according to the following:

a. Supply Ducts: 2 inch wg.

b. Return Ducts (Negative Pressure): 2 inch wg.

c. Outside Air Ducts: 2 inch wg.

d. Exhaust Ducts (Negative Pressure): 2 inch wg.

2. All ducts will be galvanized steel.

B. Duct Installation:

1. Construct and install ducts according to SMACNA’s “HVAC Duct Construction

Standards- Metal and Flexible”, unless otherwise indicated.

2. Install round ducts in lengths not less than 12 feet unless interrupted by fittings.

3. Install ducts with fewest possible joints.

4. Install fabricated fittings for changes in directions, size, and shapes and for connections required.

5. Install couplings tight to duct wall surface with a minimum of projections into duct. Secure couplings with sheet metal screws. Install screws at intervals of 12 inches, with a minimum of 3 screws in each coupling.

6. Install ducts vertically, horizontally and parallel and perpendicular with enclosure elements of building; avoid diagonal runs unless otherwise indicated.

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7. Install ducts close to walls, overhead construction, columns, and other structural and permanent enclosure elements of the building.

8. Install ducts with a clearance of 1 inch, plus allowance for insulation thickness.

9. Conceal rectangular ducts from view in finished spaces unless indicated otherwise.

Do not encase horizontal runs in solid partitions unless specifically indicated.

10. Coordinate layout with suspended lighting layouts and similar finished Work.

11. Seal all joints and seams on rectangular duct. Apply sealant to male end connectors before insertion, and afterward to cover entire joint and sheet metal screws.

12. Non-Fire-Rated Partition Penetrations: Where ducts pass through interior partitions and exterior walls and are exposed to view, conceal spaces between construction openings and ducts or duct insulation with sheet metal flanges of same metal thickness as ducts. Overlap openings on 4 sides by at least 1-1/2 inches.

13. Protect duct interiors from the elements and foreign materials until building is enclosed. Follow SMACNA’s Duct Cleanliness for New Construction” guidelines.

14. Paint interiors of metal ducts that do not have duct liner, for 24 inches upstream of registers and grilles. Apply one coat of flat black, latex finish coat over a compatible galvanized-steel primer.

15. Accept for ducts that are specified to be painted, install external insulation to all ducts in accordance with SMACNA’s duct insulation guidelines.

C. Seam and Joint Sealing:

1. Seal duct seams and joints according to SMACNA’s “HVAC Duct Construction

Standards- Metal and Flexible” for duct pressure class indicated.

a. For pressure classes lower than 2 inch wg, seal transverse joints.

2. Seal ducts before external insulation is applied.

D. Hanging and Supporting:

1. Support horizontal ducts within 24 inches of each elbow and within 48 inches of each branch intersection.

2. Install upper attachments to structures with allowable load not exceeding one-fourth of failure (proof-test) load.

E. Connections:

1. Make connections to equipment with flexible connectors according to Division

23, Section “Duct Accessories”.

2. Comply with SMACNA’s “HVAC Duct Construction Standards- Metal and

Flexible” for branch, outlets, and terminal unit connections.

F. Field Quality Control:

1. Perform the following field tests and inspections according to SMACNA’s

“HVAC Air Duct Leakage Test Manual” and prepare test reports:

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a. Disassemble, reassemble, and seal segments of systems to accommodate leakage testing and for compliance with test requirements.

b. Conduct tests at static pressure equal to maximum design pressure class of system or section being tested. If pressure classes are not indicated, test entire system at maximum system design pressure. Do not pressurize system above maximum design operating pressure. Give seven days’ advance notice for testing.

c. Maximum Allowable Leakage: Comply with requirements for Leakage Class

3 for round and flat-oval ducts, Leakage Class 12 for rectangular ducts in pressure classes lower than and equal to 2 inch wg (both positive and negative pressures), and Leakage Class 6 for pressure classes from 2 inch to 10 inch wg.

d. Remake leaking joints and retest until leakage is equal to or less than maximum allowable.

G. Cleaning New or Partial Systems:

1. Flush Out: Operate new system(s) or partial system(s) with 100 percent outside air for a minimum duration of two weeks before occupancy of the building.

2. Mark position of dampers and air-directional mechanical devices before cleaning, and perform cleaning before air balancing.

3. Use service openings, as required, for physical and mechanical entry and for inspection.

a. Create other openings to comply with duct standards.

b. Disconnect flexible ducts as needed for cleaning and inspections.

c. Remove and reinstall ceiling sections to gain access during the cleaning process.

4. Vent vacuuming system to the outside. Include filtration to contain debris removed from HVAC systems, and locate exhaust down wind and away from air intakes and other points of entry into building.

5. Clean the following metal duct systems by removing surface contaminants and deposits:

a. Air outlets and inlets (registers, grilles, and diffusers).

b. Supply, return, and exhaust fans including fan housings, plenums (except ceiling supply and return plenums), scrolls, blades, or vanes, shafts, baffles, dampers, and drive assemblies.

c. Air-handling unit internal surfaces and components including mixing box, coil section, air wash systems, spray eliminators, condensate drain pans, humidifiers and dehumidifiers, filters and filter sections, and condensate collectors, and drains.

d. Coils and related components.

e. Return-air ducts, dampers, and actuators, except in ceiling plenums and mechanical equipment rooms.

f. Supply-air ducts, dampers, actuators, and turning vanes.

6. Mechanical Cleaning Methodology:

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a. Clean metal duct systems using mechanical cleaning methods that extract contaminates from within duct systems and remove contaminates from building.

b. Use vacuum-collection devices that are operated continuously during cleaning. Connect vacuum device to downstream end of duct sections so areas being cleaned are under negative pressure.

c. Use mechanical agitation to dislodge debris adhered to interior duct surfaces without damaging integrity of metal ducts, or duct accessories.

d. Clean coils and coil drain pans according to NADCA latest Edition and

Amendments. Keep drain pans operational. Rinse coils with clean water to remove latent residues and cleaning materials; comb and straighten fins.

7. Cleanliness Verification:

a. Visually inspect metal ducts for contaminants.

b. Where contaminants are discovered, re-clean and inspect ducts.

End of Section- 23815

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SECTION 23820 – DUCT ACCESSORIES

D. Summary:

2. This Section includes the following:

a. Backdraft dampers.

b. Volume dampers.

c. Motorized control dampers.

d. Turning vanes.

e. Duct-mounting access doors.

f. Flexible connectors.

g. Flexible ducts.

h. Duct accessory hardware.

E. Related Sections:

3. Related Sections include the following:

a. Division 23, Section “HVAC Instrumentation and Controls”.

F. Quality Assurance:

3. Comply with NFPA 90A, “Installation of Air Conditioning and Ventilation

Systems”, and NFPA 90B, “Installation of Warm Air Heating and Air

4. System filtration will be MERV 13 minimum.

B. Sheet Metal Materials:

6. Comply with SMACNA’s “HVAC Duct Construction Standards- Metal and

Flexible”, for acceptable materials, material thickness, and duct construction methods, unless otherwise indicated.

7. Galvanized Sheet Steel: Lock-forming quality; complying with ASTM A 652/A

653M, and having G90 coating designation; ducts will have mill-phosphatized finish for surfaces exposed to view.

8. Reinforced Shapes and Plates: Galvanized-steel reinforcement where installed on galvanized sheet metal ducts; compatible materials for aluminum and stainless-steel ducts.

9. Tie Rods: Galvanized steel; 1/4 inch minimum diameter for lengths 36 inches or less, 3/8 inch minimum diameter for lengths longer than 36 inches.

C. Backdraft Dampers:

4. Description: Multiple-blade, parallel action, gravity balanced, with blades of maximum 6 inch width, with sealed edges, assembled in rattle-free manner with

90 degree stop, steel ball bearings, and axles; adjust device to permit setting for varying differential static pressure.

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Section 23820- Duct Accessories Cont.

D. Volume Dampers:

1. General Description: Factory fabricated, with required hardware and accessories.

Stiffen damper blades for stability. Include locking device to hold single-blade dampers in a fixed position without vibration. Close duct penetrations for damper components to seal duct consistent with pressure class.

a. Pressure Classes of 3 inch wg or Higher: end bearings or other seals for ducts with axle’s full length of damper blades and bearings at both ends of operating shaft.

2. Low-Leakage Volume Dampers: Multiple or single-blade, parallel or opposed-blade design as indicated, low-leakage rating, and suitable for horizontal or vertical applications.

3. Jackshaft: 1 inch diameter, galvanized-steel pipe rotating within pipe-bearing assembly, mounted on supports at each mullion and at each end of multiple-damper assemblies.

a. Length and Number of Mountings: Appropriate to connect leakage of each damper in multiple-damper assembly.

4. Damper Hardware: Zinc-plated, die-cast core with dial and handle made of 3/32 inch thick zinc-plated steel, and a 3/4 inch hexagon locking nut. Include center hole to suit damper operating-rod size. Include elevated platform for insulated duct mounting.

D. Motorized Control Dampers:

1. General Description: AMCA-rated, parallel-blade design; minimum of 0.1084 inch thick, galvanized-steel frames with holes for duct mounting; minimum of

0.0635 inch thick, galvanized-steel damper blades with maximum blade width of

8 inches.

a. Secure blades to 1/2 inch diameter, zinc-plated axles using zinc-plated hardware, with nylon blade bearings, blade linkage hardware of zinc-plated steel and brass, ends sealed against spring-stainless-steel blade bearings, and thrust bearings at end of every blade.

b. Operating Temperature Range: From minus 40 degrees to plus 200 degrees

F.

c. Provide parallel or opposed-blade design with inflatable seal blade edging, or replaceable rubber seals, rated for leakage at less than 10 cfm per sq. ft. of damper area, at differential pressure of 4 inch wg when damper is being held by torque of 50 in. lb.; when tested according to AMCA 500D.

E. Turning Vanes:

1. Fabricate to comply with SMACNA’s “HVAC Duct Construction Standards-

Metal and Flexible” for vanes and van runners. Vane runners will automatically align vanes.

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2. Manufactured Turning Vanes: Fabricate 1/2 inch wide, single-vane, curved blades of galvanized sheet steel set 3/4 inch o.c.; support with bars perpendicular to blades set 2 inches o.c.; and set into vane runners suitable for duct mounting.

F. Duct-Mounting Access Doors:

1. General Description: Fabricate doors airtight and suitable for duct pressure class.

2. Door: Double wall, duct mounting, and rectangular; fabricated of galvanized sheet metal with insulation fill and thickness as indicated for duct pressure class.

Include vision panel where indicated. Include 1 by1 inch butt or piano hinge and cam latches.

a. Frame: Galvanized sheet steel, with bend-over tabs and foam gaskets.

b. Provide number of hinges and locks as follows:

1. Less than 12 inches Square: Secure with two sash locks.

2. Up to 18 inches Square: Two hinges and two sash locks.

3. Seal around frame attachment to duct and door to frame with neoprene or foam rubber.

4. Insulation: 1 inch thick, fibrous-glass or polystyrene-foam board.

G. Flexible Connectors:

1. General Description: Flame-retardant or noncombustible fabrics, coatings, and adhesives complying with UL 181, Class 1.

2. Metal-edges Connectors: Factory fabricated with a fabric strip 3-1/2 inches wide, attached to two strips of 2-3/4 inch wide, 0.028 inch thick, galvanized sheet steel or 0.032 inch thick aluminum sheets. Select metal compatible with ducts.

3. Indoor system, Flexible Connector Fabric: glass-fabric, double coated with neoprene.

a. Minimum Weight: 26 oz. /sq. yd.

b. Tensile Strength: 480 lbf/inch in the wrap and 360 lbf/inch in the filling.

c. Service Temperature: Minus 40 degrees to 200 degrees F.

H. Flexible Ducts:

1. Insulated-Duct Connectors: UL 181, Class 1, 2-ply vinyl film supported by helically wound, spring-steel wire; fibrous-glass insulation; polystyrene vapor barrier film.

a. Pressure Rating: 10 inch wg positive and 1.0 inch wg negative.

b. Maximum Air Velocity: 4000 fpm.

c. Temperature Range: Minus 10 degrees to plus 160 degrees F.

2. Flexible Duct Clamps: Stainless-steel band with cadmium-plated hex screw to tighten band with a worm-gear action, in sizes 3 through 18 inches to suit duct size.

I. Duct Accessory Hardware:

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1. Instrument Test Holes: Cast-iron or cast aluminum to suit duct material, including screw cap and gasket. Size to allow insertion of pilot tube and other testing instruments and length to suit duct insulation thickness.

2. Adhesives: High strength, quick setting, neoprene based, waterproof, and resistant to gasoline and grease.

A. Application and Installation:

2. Install duct accessories according to applicable details in SMACNA’s “HVAC

Duct Construction Standards- Metal and Flexible”.

3. Provide duct accessories of materials suited to duct materials; use galvanized-steel accessories in galvanized-steel.

4. Install backdraft dampers on exhaust fans or exhaust ducts nearest to outside and where indicated.

5. Provide balancing dampers at points on supply, return, and exhaust systems where branches lead from larger ducts as required for balancing. Install at a minimum of two duct widths from branch takeoff.

6. Install duct access doors to allow for inspecting, adjusting, and maintaining accessories and terminal units as follows:

a. Downstream from volume dampers and equipment.

b. To interior of ducts for cleaning; before and after each change in direction, at maximum 50 foot spacing.

c. On sides of ducts where adequate clearance is available.

7. Install the following sizes for duct-mounting, rectangular access doors:

a. One-Hand or Inspection Access: 8 by 5 inches.

b. Two-Hand Access: 12 by 6 inches.

c. Head and Hand Access: 18 by 10 inches.

8. Label access doors according to Division 22, Section “Mechanical

Identification”.

9. Install flexible connectors supported by vibration isolators immediately adjacent to equipment in ducts associated with fans and motorized equipment.

10. Connect diffusers boots to low pressure ducts with maximum 60 inch lengths of flexible duct, clamped or strapped in place.

11. Connect flexible ducts to metal ducts with mechanical fasteners through metal ring, with liquid adhesive plus tape.

12. Install duct test holes where required for testing and balancing purposes.

B. Adjusting:

1. Adjust duct accessories for proper settings.

2. Final positioning of manual-volume dampers is specified in division 23, Section

“Testing, Adjusting, and Balancing”.

End of Section- 23820

18 Division 23 - HVAC

SECTION 23855 – DIFFUSERS, REGISTERS, AND GRILLES

G. Summary:

3. This Section includes ceiling and wall mounted diffusers, registers, and grilles.

H. Related Sections:

4. Related Sections include the following:

a. Division 23, Section “Duct Accessories”.

C. Quality Assurance:

5. Comply with NFPA 90A, “Installation of Air Conditioning and Ventilation

Systems”, and NFPA 90B, “Installation of Warm Air Heating and Air

E. Manufacturers:

1. Available Manufacturers: Subject to compliance with requirements, manufacturers offering products that may be incorporated into the Work include, but are not limited to, the following:

a. Supply Diffuser:

1. Louvered Fixed Pattern with dampener, 24”x24”, T-Bar, 360 deg. pattern, Lay-In. Comparable to Air Mate,

2. Model- 782-SA with deflectors.

3. White

b. Return Diffuser:

1. Perforated Face, 24”x24”, T-Bar, Lay-In. Comparable to Air Mate,

2. Model- 782-RA.

3. White.

B. Source quality Control:

10. Obtain all diffusers, registers, and grille one manufacturer and one supplier for the entire project. Engage a supplier that has the means to supply necessary products in a timely manner as to not cause delay in the work.

11. Verification of Performance: Rate diffusers, registers, and grilles according to

ASHRAE 70, “Method of Testing for Rating the Performance of Air Outlets and

Inlets”.

A. Examination:

19 Division 23 - HVAC

1. Examine areas where diffusers, registers, and grilles are to be installed for compliance with requirements for installation tolerances and other conditions affecting performance of equipment.

Section 23855- Diffusers, Registers, and Grilles Cont.

2. Proceed with installation only after unsatisfactory conditions have been corrected.

H. Installation:

1. Install diffusers, registers, and grilles securely in suspension grid; level and plumb and free from rattles.

2. Ceiling Mounted Outlets and Inlets: Drawings indicate general arrangement of ducts, fittings, and accessories. Air outlet and inlet locations have been indicated to achieve design requirements for air volume, noise criteria, airflow pattern, throw, pressure drop. Make final locations where indicated, as much as practicable. For units installed in lay-in ceiling panels, locate units in the center of the panel. Where architectural features or other items conflict with installation, notify ESD PM for a determination of final location.

3. Install diffusers, registers, and grilles with airtight connections to ducts and to allow service and maintenance of dampers.

I. Adjusting:

1. After installation, adjust diffusers, registers, and grilles to air patterns indicated, or as directed, before starting air balancing.

End of Section- 23855

20 Division 23 - HVAC

SECTION 23990 – TESTING, ADJUSTING, AND BALANCING

I. Summary:

4. This Section includes testing, adjusting, and balancing HVAC systems to produce design objectives, including the following:

a. Balancing airflow and water flow within distribution systems, including submains, branches, and terminals, to indicated quantities according to specified tolerances.

b. Adjusting total HVAC systems to provide indicated quantities.

c. Measuring electrical performance of HVAC equipment.

d. Setting quantitative performance of HVAC equipment.

e. Verifying that automatic control devices are functioning properly.

f. Measuring sound and vibration.

g. Reporting results of the activities and procedures specified in the Section.

J. Definitions:

1. Adjust: To regulate fluid flow rate and air patterns at the terminal equipment, such as to reduce fan speed or adjust a damper.

2. Balance: To proportion flows within the distribution system, including submains, branches, and terminals, according to design quantities.

3. Draft: A current of air, when referring to localized effect caused by one or more factors of high air velocity, low ambient temperature, or direction of airflow, whereby more heat is withdrawn from a person’s skin than is normally dissipated.

4. Procedure: An approach to and execution of a sequence of Work operations to yield repeatable results.

5. Report forms: Test data sheets for recording test data in a logical order.

6. Static Head: The pressure due to the weight of the fluid above the point of measurement. In a closed system, static head is equal on both sides of the pump.

7. Suction Head: The height of fluid above the centerline of the pump on the suction side.

8. System Effect: A phenomenon that can create undesired or unpredicted conditions that cause reduced capacities in all or part of a system.

9. System effect Factors: allowances used to calculate a reduction of the performance ratings of a fan when installed under conditions different from those presented when the fan was performance tested.

10. Terminal: A point where the controlled medium, such as fluid or energy, enters or leaves the distribution system.

11. Test: A procedure to determine quantitative performance of a system or equipment.

12. Testing, Adjusting, and Balancing Agent: The entity responsible for performing and reporting the testing, adjusting, and balancing procedures.

13. AABC: Associated Air Balance Council.

14. AMCA: Air Movement and Control Association.

Section 23990- Testing, Adjusting, and Balancing Cont.

21 Division 23 - HVAC

D. Quality Assurance:

6. Agent Qualifications: engage a testing, adjusting, and balancing agent certified by AABC.

7. Testing, Adjusting, and balancing Conference: Meet with ESD PM and

Inspections, Contractor, and subcontractor on approval of the testing, adjusting, and balancing strategies and procedures plan, to develop a mutual understanding of the details. Ensure the participation of the testing, adjusting, and balancing team members, equipment manufacturer’s authorized service representatives, HVAC controls Installer, and other support personnel. Provide 7 calendar days advance notice of scheduled meeting time and location.

8. Agenda Items:

a. Submittal distribution requirements.

b. Contract documents examination report.

c. Testing, adjusting, and balancing plan.

d. Work schedule and Project site access requirements.

e. Coordination and cooperation of trades and subcontractors.

f. Coordination of documentation and communication flow.

9. Testing, Adjusting, and Balancing Reports: Use standard forms from AABC’s

“National Standards for Testing, Adjusting, and Balancing”.

10. Instrument Type, Quantity, and Accuracy: As described in AABC national standards.

11. Instrumentation Calibration: Calibrate instruments at least every 6 months or more frequently of required by the instrument manufacturer.

E. Project Condition:

1. Partial Occupancy: The Government may occupy completed areas of the building before Substantial Completion. Cooperate with the Occupant during testing, adjusting, and balancing operations to minimize conflicts with the Occupant.

F. Coordination:

1. Coordinate the efforts of factory-authorized service representatives for systems and equipment, HVAC controls installers, and other mechanics to operate HVAC systems and equipment to support and assist testing, adjusting, and balancing activities.

2. Notice: Provide 7 calendar days advance notice for each test. Include schedule test dates and times.

3. Perform testing, adjusting, and balancing after leakage and pressure tests on air and water distribution systems have been satisfactorily completed.

PART 2 – PRODUCTS (Not Applicable)

22 Division 23 - HVAC

B. Examination:

3. Examine Contract Documents to become familiar with Project requirements and to discover conditions in systems’ designs that may preclude proper testing, adjusting, and balancing of systems and equipment.

a. Verify that balancing devices, such as test ports, gage cocks, thermometer wells, flow-control devices, balancing valves and fittings, and manual volume dampers are required and working properly. Verify that quantities and locations of these balancing devices are accessible and appropriate for effective balancing and for efficient system and equipment operation.

4. Examine approved submittal data of HVAC systems and equipment.

5. Examine system and equipment installations to verify that they are complete and that testing, cleaning, adjusting, and commissioning specified in individual

Specification Sections have been performed.

6. Examine terminal, units, such as variable-air-volume boxes and mixing boxes, to verify that they are accessible and their controls are connected and functioning.

7. Examine heat-transfer coils for correct piping connections and for clean and straight fins.

8. Examine automatic temperature system components to verify the following:

a. Dampers, valves, and other controlled devices operate by the intended controller.

b. Dampers and valves are in the position indicated by the controller.

c. Integrity of valves and dampers for free and full operation and for tightness of fully closed and fully opened positions. This includes dampers variable-air-volume terminals.

d. Automatic modulating and shutoff valves, including 2-way valves and 3-way mixing and diverting valves, are properly connected.

e. Thermostats are located to avoid adverse effects of sunlight, drafts, and cold walls.

f. Sensors are located and installed to sense only the intended conditions.

g. Sequence of operation for control modes is according to the Contract

Documents.

h. Controller set point are set at design values. Observe and record system reactions to changes in conditions. Record default set points if different from design values.

i. Interlocked systems are operating.

j. Changeover from heating to cooling mode occurs according to design values.

9. Report deficiencies discovered before and during performance of testing, adjusting, and balancing procedures.

J. Preparation:

1. Prepare a testing, adjusting, and balancing plan that includes strategies and step-by-step procedures.

23 Division 23 - HVAC

2. Complete systems readiness checks and prepare system readiness reports. Verify the following:

a. Permanent electrical power wiring is complete.

b. Hydronic systems are filled, clean, and free of air.

c. Automatic temperature-control systems are operational.

d. Equipment and duct access doors are securely closed.

e. Balance and fire dampers are open.

f. Isolating and balancing valves are open and control valves are operational.

g. Ceilings are installed in critical areas where air-pattern adjustments are required and access to balancing devices is provided.

h. Windows and doors can be closed so design conditions for system operations can be met.

K. General Testing and Balancing:

1. Perform testing and balancing procedures on each system according to the procedures contained in AABC national standards and this Specification.

2. Cut insulation, ducts, pipes, and equipment cabinets for installation of test probes to the minimum extent necessary to allow adequate performance of procedures.

After testing and balancing, close probe holes and patch insulation with new materials identical to those removed. Restore vapor barrier and finish according to the insulation Specifications for the Project.

3. Mark equipment setting with paint or other suitable, permanent identification material, including damper-control positions, valve indicators, fan-speed-control levers, and similar controls and devices, to show final settings.

L. Fundamental Air Systems’ Balancing Procedures:

4. Prepare tests for both fans and outlets. Obtain manufacturers’ outlet factors and recommendations testing procedures. Crosscheck the summation of required outlet volumes with required fan volumes.

5. Prepare schematic diagrams of systems’ “as-built” duct layouts.

6. For variable-air-volume systems, develop a plan to simulate diversity.

7. Determine the best locations in main and branch ducts for accurate duct airflow measurements.

8. Check the airflow patterns from the outside-air louvers and dampers and the airflow and exhaust-air dampers, through the supply-fan discharge and mixing dampers.

9. Locate start-stop and disconnect switches, electrical interlocks, and motor starters.

10. Verify that motor starters are equipped with properly sized thermal protection.

11. Check dampers for proper position to achieve desired airflow path.

12. Check for airflow blockages.

13. Check condensate drains for proper connections and functions.

14. Check for proper sealing of air-handling unit components.

24 Division 23 - HVAC

M. Constant-Volume Air Systems’ Balancing Procedures::

2. The procedures in this Article apply to constant-volume supply-return-and exhaust-air systems. Additional procedures are required for variable-air-volume, multizone, dual-duct, induction-unit supply-air systems and process exhaust-air systems. These additional procedures are specified in other Articles in the

Specification.

3. Adjust fans to deliver total design airflows within the maximum allowable rpm listed by the fan manufacturer.

a. Measure fan static pressure to determine actual static pressure as follows:

1. Measure outlet static pressure as far downstream from the fan as practicable and upstream from restrictions in ducts such as elbows and transitions as practicable.

2. Measure static pressure directly at the fan outlet or through the flexible connection.

3. Measure inlet static pressure of single-inlet fans in the inlet duct as near the fan as possible, upstream from flexible connection and downstream from duct restrictions.

4. Measure inlet static pressure of double-inlet fans through the wall of the plenum that houses the fan.

b. Measure static pressure across each air-handling unit component.

1. Simulate dirty filter operation and record the point at which maintenance personnel must change filters.

c. Measure static pressures entering and leaving other devices such as sound traps, heat recovery equipment, and air washers under final balance conditions.

d. Adjust fan speed higher or lower than design values within the maximum allowable rpm listed by the fan manufacturer. Make required adjustments to pulley sizes, motor sizes, and electrical connections to accommodate fan-speed changes.

e. Do not make fan-speed adjustments that result in motor overload. Consult equipment manufacturers about fan-speed safety factors. Modulate dampers and measure fan-motor amperage to ensure no overload will occur. Measure required brake horsepower.

3. Adjust volume dampers for main duct, sub-main ducts, and major branch ducts to design airflows within specified tolerances.

a. Measure static pressure at a point downstream from the balancing damper and adjust volume dampers until the proper static pressure is achieved.

1. Where sufficient space sub-main and branch ducts is unavailable for Pilot-tube traverse measurements, measure airflow at terminal outlets and inlets and calculate the total airflow for that zone.

b. Remeasure each sub-main and branch duct after all have been adjusted.

Continue to adjust sub-mains and branch ducts to design airflows within specified tolerances.

4. Measure terminal outlets and inlets without making adjustments.

25 Division 23 - HVAC

a. Measure terminal outlets using a direct-reading hood or the outlet manufacturer’s written instructions and calculating factors.

5. Adjust terminal outlets and inlets for each space to design airflows within specified tolerances of design values. Make adjustments using volume dampers rather than extractors and the dampers at the air terminals.

a. Adjust each outlet in the same room or space to within specified tolerances of design quantities without generating noise levels above the limitations prescribed by the Contract Documents.

b. Adjust patterns of adjustable outlets for proper distribution without drafts.

N. Variable-Air-Volume Systems’ Additional Procedures:

1. Compensating for Diversity: When the total air flow of all terminal units is more than the fan design airflow volume, place a selected number of terminal units at a maximum set-point airflow condition until the total airflow of the terminal units equals the design airflow of the fan. Select the reduced airflow terminal units so they are distributed evenly among the branch ducts.

2. Pressure-Independent, Variable-Air-Volume Systems: After the fan systems have been adjusted, adjust the variable-air-volume systems as follows:

a. Set outside-air dampers at minimum, and return and exhaust-air dampers at a position that simulates full-cooling load.

b. Select the terminal unit that is most critical to the supply-fan airflow and static pressure. Measure static pressure. Adjust system static pressure so the entering static pressure for the critical terminal unit is not less than the sum of the terminal unit manufacturer’s recommended minimum inlet static pressure plus the static pressure needed to overcome terminal-unit discharge duct losses.

c. Measure total system airflow. Adjust to within 1o percent of design flow.

d. Set terminal units at maximum airflow and adjust controllers of regulator to deliver the designed maximum airflow.