23 05 93 Testing Adjusting Balancing HVAC 2023 03 22.pdf

03-01-23

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SECTION 23 05 93

TESTING, ADJUSTING, AND BALANCING FOR HVAC

PART 1 - GENERAL

1.1 DESCRIPTION

A. A complete listing of common acronyms and abbreviations are included in

Section 23 05 11, COMMON WORK RESULTS FOR HVAC.

B. Testing, adjusting, and balancing (TAB) of heating, ventilating and air conditioning (HVAC) systems. TAB includes the following:

1. Planning systematic TAB procedures.

2. Design Review Report.

3. Systems Inspection Report.

4. Duct Air Leakage Test Report.

5. Systems Readiness Report.

6. Balancing air and water distribution systems; adjustment of total system to provide design performance; and testing performance of equipment and automatic controls.

7. Vibration and sound measurements.

8. Recording and reporting results.

9. Document critical paths of flow on reports.

C. Definitions:

1. Basic TAB used in this Section: Chapter 39, "Testing, Adjusting and

Balancing" of ASHRAE Handbook "HVAC Applications".

2. TAB: Testing, Adjusting and Balancing; the process of checking and adjusting HVAC systems to meet design objectives.

3. AABC: Associated Air Balance Council.

4. NEBB: National Environmental Balancing Bureau.

5. TABB: Testing Adjusting and Balancing Bureau.

6. SMACNA: Sheet Metal and Air Conditioning Contractors’ National

Association.

7. Hydronic Systems: Includes chilled water, heating hot water.

8. Air Systems: Includes all outside air, supply air, return air, exhaust air and relief air systems.

9. Flow Rate Tolerance: The allowable percentage variation, minus to plus, of actual flow rate from values (design) in the contract documents.

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1.2 APPLICABLE PUBLICATIONS

A. The following publications form a part of this specification to the extent referenced. The publications are referenced in the text by the basic designation only. Where conflicts occur these specifications and the VHA HVAC Design Guide standards and written instructions from the

COR will govern.

B. American Society of Heating, Refrigerating and Air Conditioning

Engineers, Inc. (ASHRAE):

2019....................ASHRAE Handbook – HVAC Applications, Chapter

39, Testing, Adjusting, and Balancing and

Chapter 49, Noise and Vibration Control

C. Associated Air Balance Council (AABC):

2016....................National Standards for Total System Balance, 7th

Edition

D. National Environmental Balancing Bureau (NEBB):

2019....................Procedural Standard for Testing, Adjusting, and

Balancing of Environmental Systems, 9th Edition

2015....................Procedural Standard for the Measurement of

Sound and Vibration, 2nd Edition

S110-2019...............Whole Building Technical Commissioning of New

Construction, 2nd Edition

E. Sheet Metal and Air Conditioning Contractors National Association

(SMACNA):

2002....................HVAC Systems Testing, Adjusting and Balancing, 3rd Edition

2003....................TAB Procedural Guide 1st Edition

1.4 SUBMITTALS

B. Information and material submitted under this section shall be marked

“SUBMITTED UNDER SECTION 23 05 93, Testing, Adjusting and Balancing for

HVAC”, with applicable paragraph identification.

C. Submit names and qualifications of TAB agency and TAB Specialists to the contracting officer with the contractor’s proposal. Submit information on three recently completed projects and a list of proposed test equipment.

D. For use by the COR staff, submit one complete set of applicable AABC, NEBB or TABB publications that will be the basis of TAB work.

E. Submit the following for review and approval:

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1. Intermediate and Final TAB reports covering flow balance and adjustments, performance tests, vibration tests and sound tests.

2. Include in final reports uncorrected installation deficiencies noted during TAB and applicable explanatory comments on test results that differ from design requirements. Include other information as directed by the COR to facilitate troubleshooting.

F. Prior to request for Final or Partial Final inspection, submit completed Test and Balance report for the area with noted critical paths.

1.5 QUALITY ASSURANCE

A. Qualifications:

1. The TAB agency shall not have been the subject of disciplinary action by either the AABC, TABB or NEBB within the five (5) years preceding Contract Award shall not be eligible to perform any work related to the TAB. All work performed in this Section and in other related Sections by the TAB agency shall be considered invalid if the TAB agency loses its certification prior to Contract completion, and the successor agency’s review shows unsatisfactory work performed by the predecessor agency.

2. TAB Specialist: The TAB Specialist shall be either a member of AABC or TABB or an experienced technician of the Agency certified by

NEBB. The certification shall be maintained for the entire duration of duties specified herein. If, for any reason, the Specialist loses subject certification during this period, the contractor shall immediately notify the COR and submit another TAB Specialist for approval. Any individual that has been the subject of disciplinary action by either the AABC or the NEBB within the five (5) years preceding Contract Award shall not be eligible to perform any duties related to the HVAC systems, including TAB. All work specified in this Section and in other related Sections performed by the TAB

Specialist shall be considered invalid if the TAB Specialist loses its certification prior to Contract completion and shall be performed by an approved successor.

3. TAB Specialist shall be identified by the contractor in writing and submitted to the contracting officer and COR with their proposal.

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The TAB Specialist will be coordinating, scheduling, and reporting all TAB work and related activities and will provide necessary information as required by the COR. The responsibilities shall specifically include:

a. Being on site and directly supervising all TAB work.

b. Sign the TAB reports that bear the seal of the TAB standard. The reports shall be accompanied by report forms and schematic drawings required by the TAB standard, AABC, TABB or NEBB.

c. Following all TAB work through its satisfactory completion.

d. Providing final markings of settings of all HVAC adjustment devices.

e. Permanently mark location of duct test ports.

f. Documenting critical paths from the fan or pump. These critical paths are ones in which are 100 percent open from the fan or pump to the terminal device. This will show the least amount of restriction is being imposed on the system by the TAB firm.

4. All TAB technicians performing actual TAB work shall be experienced and shall have done satisfactory work on a minimum of three (3) projects comparable in size and complexity to this project.

Qualifications shall be certified by the TAB agency in writing and submitted to the contracting officer with their proposal. The lead technician shall be certified by AABC, TABB or NEBB.

B. Test Equipment Criteria: The instrumentation shall meet the accuracy/calibration requirements established by AABC National

Standards, TABB/SMACNA International Standards, or by NEBB Procedural

Standard for Testing, Adjusting and Balancing of Environmental Systems and instrument manufacturer. Provide calibration history of the instruments to be used for test and balance purpose. All equipment shall remain in calibration, or be re-calibrated if certification expires, during the TAB procedures.

D. TAB Criteria:

1. One or more of the applicable AABC, NEBB, TABB or SMACNA publications, supplemented by Chapter 39, "Testing, Adjusting and

Balancing" of ASHRAE Handbook "HVAC Applications", VHA HVAC Design

Guide and requirements stated herein shall be the basis for planning, procedures, and reports. The VHA Design Guide supersedes all other documents.

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2. Flow Rate Tolerance: Following tolerances are allowed. For tolerances not mentioned herein follow Chapter 39, "Testing, Adjusting and Balancing" of ASHRAE Handbook "HVAC Applications" as a guideline. Air Filter resistance during tests, artificially imposed, if necessary, shall be at least 100 percent of manufacturer recommended change over pressure drop values for pre-filters and after-filters.

a. Air handling unit and all other fans, cubic meters/min (cubic feet per minute): Minus 5 percent to plus l0 percent.

b. Air Terminal Units (maximum values): Minus 5 percent to plus l0 percent

c. Exhaust Hoods/Cabinets: 0 percent to plus l0 percent.

d. Minimum Outside Air: 0 percent to plus 10 percent.

e. Individual room air outlets and inlets, and air flow rates not mentioned above: Minus 5 percent to plus l0 percent except if the air-to-air space is 100 CFM or less the tolerance will be minus 5 to plus 5 percent.

f. Heating Hot Water Pumps and Hot Water Coils: Minus 5 percent to plus 5 percent.

g. Chilled Water and Condenser Water Pumps: Minus 5 percent to plus

5 percent.

h. Chilled Water Coils: Minus 5 percent to plus 5 percent.

3. Systems shall be adjusted for energy efficient operation as described in PART 3.

4. Typical TAB procedures and critical path results shall be demonstrated to the COR for one air distribution system (including all fans, 3 terminal units, 3 rooms randomly selected by the COR, one of which shall be a critical path) and 1 hydronic system (pumps and 3 coils) as follows:

a. When field TAB work begins.

b. During each partial final inspection and the final inspection for the project if requested by VA.

PART 2 - PRODUCTS

2.1 PLUGS

A. Provide plastic plugs to seal holes drilled in ductwork for test purposes.

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2.2 INSULATION REPAIR MATERIAL

A. See Section 23 07 11, HVAC, and BOILER PLANT INSULATION. Provide for repair of insulation removed or damaged for TAB work.

PART 3 - EXECUTION

3.1 GENERAL

A. Refer to TAB Criteria in Paragraph QUALITY ASSURANCE.

B. Obtain applicable contract documents and copies of approved submittals for HVAC equipment and automatic control systems.

3.2 DESIGN REVIEW REPORT

A. The TAB Specialist shall review the contract documents and advise the

COR of any design deficiencies that would prevent the HVAC systems from effectively operating in accordance with the sequence of operation specified or prevent the effective and accurate TAB of the system. The

TAB Specialist shall provide a report individually listing each deficiency and the corresponding proposed corrective action necessary for proper system operation.

3.4 SYSTEM READINESS REPORT

A. The TAB Contractor shall measure existing air and water flow rates associated with existing systems utilized to serve renovated areas as indicated in the contract documents. Submit report of findings to COR.

B. Inspect each system to ensure that it is complete including installation and operation of controls. Submit report to COR in standard format and forms prepared and/or approved by the CxA.

C. Verify that all items such as ductwork piping, dampers, valves, ports, terminals, connectors, etc., that are required for TAB are installed.

Provide a report to the COR.

3.5 TAB REPORTS

A. The TAB Contractor shall provide raw data immediately in writing to the

COR if there is a problem in achieving intended results before submitting a formal report.

B. If over 20 percent of readings in the intermediate report fall outside the acceptable range, the TAB report shall be considered invalid, and all contract TAB work shall be repeated after engineering and construction have been evaluated and re-submitted for approval at no additional cost to the Governmnet.

C. Do not proceed with the remaining systems until intermediate report is approved by the COR or the COR otherwise allows.

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3.6 TAB PROCEDURES

A. TAB shall be performed in accordance with the requirement of the

Standard under which TAB agency is certified by either AABC, TABB or

NEBB. Balancing shall be done proportionally to all applicable systems.

1. At least 1 trunk damper shall be 100 percent open.

2. At least 1 branch damper shall be 100 percent open per trunk.

3. At least 1 terminal device duct be 100 percent open per branch.

4. At least one hydronic balancing valve shall be 100 percent open per hydronic system.

B. General: During TAB all related system components shall be in full operation. Fan and pump rotation, motor loads and equipment vibration shall be checked and corrected as necessary before proceeding with TAB.

Set controls and/or block off parts of distribution systems to simulate design operation of variable volume air or water systems for test and balance work.

C. Air Balance and Equipment Test: Include air-handling units, fans, terminal units, fan coil units, room diffusers/outlets/inlets, computer room AC units, and laboratory fume hoods and biological safety cabinets.

1. Artificially load air filters by partial blanking to produce static air pressure drop of manufacturer’s recommended pressure drop.

2. Adjust fan speeds to provide design air flow. Provide new drive sets as required to adjust fan speeds.

3. Test and balance systems in all specified modes of operation, including variable volume, economizer, and fire emergency modes.

Verify that dampers and other HVAC controls function properly.

4. Variable Air Volume (VAV) Systems:

a. Coordinate TAB, including system volumetric controls, with

Section 23 09 23, DIRECT-DIGITAL CONTROL SYSTEM FOR HVAC.

b. Check and readjust ATU flow rates if necessary to meet design criteria. Balance air distribution from ATU on full cooling maximum scheduled cubic meters per minute (cubic feet per minute). Reset room thermostats and check ATU operation from maximum to minimum cooling, to the heating mode, and back to cooling. Record and report the heating coil leaving air temperature when the ATU is in the maximum heating mode. Record and report outdoor air flow rates under all operating conditions

(The test shall demonstrate that the minimum outdoor air

23 05 93 - 8 ventilation rate shall remain constant under all operating conditions).

c. Adjust operating pressure control setpoint to maintain the design flow to each space with the lowest setpoint. Confirm static pressure reset is operational and functioning properly.

5. Record final measurements for air handling equipment performance data sheets.

6. Record final damper settings for all manual volume dampers.

D. Rooms with Specific Pressure Relationships Including, Operating Rooms, Isolation Rooms, Pharmacy Compounding, SPS:

1. For rooms that require specific pressure relationships as noted in the contract documents report the following information:

a. Room differential pressure at minimum and maximum flows.

b. Room air changes per hour (ACH).

c. Adjust airflows to achieve the required air pressure relationships. Increase/decrease the supply/exhaust airflow as needed. For positively pressurized rooms the supply airflow shall be set per the contract documents and return/exhaust airflow shall be adjusted to achieve the required pressure relationship.

For negatively pressurized rooms the exhaust airflow per the contract documents and the supply airflow adjusted to achieve the required pressure relationship.

E. Water Balance and Equipment Test: Include circulating pumps, convertors, coils, coolers and condensers:

1. Coordinate water chiller flow balancing with Section 23 64 00, PACKAGED WATER CHILLERS.

2. Adjust flow rates for equipment. Set coils and evaporator to values on equipment submittals, if different from values in the contract documents.

3. Primary-Secondary (variable volume) Systems: Coordinate TAB with

Section 23 09 23, DIRECT-DIGITAL CONTROL SYSTEM FOR HVAC. Balance systems at design water flow and then verify that variable flow controls function as designed.

4. Record final measurements for hydronic equipment on performance data sheets. Include entering and leaving water temperatures for heating and cooling coils, and for convertors. Include entering and leaving air temperatures (DB/WB for cooling coils) for air-handling units

23 05 93 - 9 and reheat coils. Make air and water temperature measurements at the same time.

5. On coils with automatic flow limiting valves (automatic balancing valves) measure and report Delta P across valve and measure Delta P across 100 percent open temperature control valve and using control valve CV calculate and report gpm.

6. Record final valve setting for all balancing valves.

3.7 VIBRATION TESTING

A. Furnish instruments and perform vibration measurements as specified in

Section 23 05 41, NOISE and VIBRATION CONTROL FOR HVAC PIPING and

EQUIPMENT. Field vibration balancing is specified in Section 23 05 11, COMMON WORK RESULTS FOR HVAC Section 23 05 10, COMMON WORK RESULTS FOR

BOILER PLANT and STEAM GENERATION. Provide measurements for all rotating HVAC equipment of 373 watts (1/2 horsepower) and larger, including centrifugal/screw compressors, cooling towers, pumps, fans and motors.

B. Record initial measurements for each unit of equipment on test forms and submit a report to the COR. Where vibration readings exceed the allowable tolerance Contractor shall be directed to correct the problem. The TAB agency shall verify that the corrections are done and submit a final report to the COR.

3.8 SOUND TESTING

A. Perform and record required sound measurements in accordance with paragraph QUALITY ASSURANCE in Section 23 05 41, NOISE and VIBRATION

CONTROL FOR HVAC PIPING and EQUIPMENT.

1. Take readings in rooms, approximately three five (5) percent of all rooms. The COR may designate the specific rooms to be tested.

2. Provide chiller and cooling tower sound measurements. Refer to

Section 23 64 00, PACKAGED WATER CHILLERS and Section 23 65 00, COOLING TOWERS.

B. Take measurements with a calibrated sound level meter and octave band analyzer of the accuracy required by AABC, TABB or NEBB.

C. Sound reference levels, formulas and coefficients shall be according to

ASHRAE Handbook "HVAC Applications", Chapter 49, “Noise and Vibration

Control”.

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D. Determine compliance with contract documents as follows:

1. When sound pressure levels are specified, including the NC Criteria in Section 23 05 41, NOISE and VIBRATION CONTROL FOR HVAC PIPING and

EQUIPMENT:

a. Reduce the background noise as much as possible by shutting off unrelated audible equipment.

b. Measure octave band sound pressure levels with specified equipment "off."

c. Measure octave band sound pressure levels with specified equipment "on."

d. Use the DIFFERENCE in corresponding readings to determine the sound pressure due to equipment.

DIFFERENCE: 0 1 2 3 4 5 to 9 10 or More

FACTOR: 10 7 4 3 2 1 0

Sound pressure level due to equipment equals sound pressure level with equipment "on" minus FACTOR.

e. Plot octave bands of sound pressure level due to equipment for typical rooms on a graph which also shows noise criteria (NC) curves.

2. When sound power levels are specified:

a. Perform steps 1.a. through 1.d., as specified above.

b. For Indoor Equipment: Determine room attenuating effect, i.e., difference between sound power level and sound pressure level.

Determined sound power level will be the sum of sound pressure level due to equipment plus the room attenuating effect.

c. For Outdoor Equipment: Use directivity factor and distance from noise source to determine distance factor, i.e., difference between sound power level and sound pressure level. Measured sound power level will be the sum of sound pressure level due to equipment plus the distance factor. Use 9 meters (30 feet) for sound level location.

3. Where sound pressure levels are specified in terms of dB(A), as in

Section 23 65 00, COOLING TOWERS, measure sound levels using the "A" scale of meter. Single value readings will be used instead of octave band analysis.

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E. Where measured sound levels exceed specified level, the installing contractor or equipment manufacturer shall take remedial action approved by the COR and the necessary sound tests shall be repeated.

F. Test readings for sound testing could go higher than 15 percent if determination is made by the COR based on the recorded sound data.

3.9 MARKING OF SETTINGS

A. Following approval of TAB Final Report, the setting of all HVAC adjustment devices including valves, splitters and dampers shall be permanently marked by the TAB Specialist so that adjustment can be restored if disturbed at any time. Style and colors used for markings shall be coordinated with the COR.

3.10 IDENTIFICATION OF TEST PORTS

A. The TAB Specialist shall permanently and legibly identify the location points of duct test ports. If the ductwork has exterior insulation, the identification shall be made on the exterior side of the insulation.

All penetrations through ductwork and ductwork insulation shall be sealed to prevent air leaks and maintain integrity of vapor barrier.

3.11 PHASING

A. Phased Projects: Testing and Balancing Work to follow project with areas shall be completed per the project phasing. Upon completion of the project all areas shall have been tested and balanced per the contract documents.

B. Existing Areas: Systems that serve areas outside of the project scope shall not be adversely affected. Measure existing parameters where shown to document system capacity.

3.12 CRITICAL FLOW PATH

A. Provide a documented critical path for all fluid flows. There shall be at least one (1) terminal device that can be traced back to the fan or pump where there is no damper or valves that are less than 100 percent open.