SECTION 15990 HVAC & HYDRONIC SYSTEM TESTING, ADJUSTING AND BALANCING
PART 1 - GENERAL
1.1 SUMMARY
A. This Section includes TAB to produce design objectives for the following:
1. Air Handling Systems:
a. Makeup Air Units & ductwork distributions systems
b. Furnaces and ductwork distribution systems.
c. Ductless Split Systems
d. HVAC Fans – Exhaust/Supply & Transfer fans & fan ductwork systems
e. Damper interlocks
f. Equipment interlocks
g. Hydronic Heating systems:
1) Hydronic- Hot Water Unit Heaters
2) Hydronic balancing including existing pumps
2. HVAC equipment quantitative-performance settings.
3. HVAC Control System Commissioning: Verify that Automatic Control Systems
& Devices are functioning properly.
4. Reporting results of activities and procedures specified in this Section.
1.2 DEFINITIONS
A. Adjust: To regulate fluid flow rate and air patterns at the terminal equipment, such as to reduce fan speed or adjust a damper.
B. Balance: To proportion flows within the distribution system, including submains, branches, and terminals, according to indicated quantities.
C. Balancing Devices: All installed devices necessary to achieve proper balancing of the system such as test ports, gage cocks, thermometer wells, flow-control devices, balancing valves and fittings, and manual volume dampers.
D. Barrier or Boundary: Construction, either vertical or horizontal, such as walls, floors, and ceilings that are designed and constructed to restrict the movement of airflow, smoke, odors, and other pollutants.
E. NC: Noise criteria.
F. Procedure: An approach to and execution of a sequence of work operations to yield repeatable results.
G. Report Forms: Test data sheets for recording test data in logical order.
H. System Effect: A phenomenon that can create undesired or unpredicted conditions that cause reduced capacities in all or part of a system.
I. 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.
J. TAB: Testing, adjusting, and balancing.
K. Terminal: A point where the controlled medium, such as fluid or energy, enters or leaves the distribution system.
L. Test: A procedure to determine quantitative performance of systems or equipment.
M. Testing, Adjusting, and Balancing (TAB) Firm: The entity responsible for performing and reporting TAB procedures.
1.3 SUBMITTALS
A. Certified TAB Reports: Submit two copies of reports prepared, as specified in this Section, on approved forms certified by TAB firm.
1.4 QUALITY ASSURANCE
A. TAB Firm Qualifications: Engage a TAB firm certified by either AABC or NEBB.
B. TAB Conference: Meet with Owner and Engineer's representatives on approval of TAB strategies and procedures plan to develop a mutual understanding of the details. Ensure the participation of TAB team members, equipment manufacturers' authorized service representatives, HVAC controls installers, and other support personnel. Provide seven days' advance notice of scheduled meeting time and location.
1. Agenda Items: Include at least the following:
a. Submittal distribution requirements.
b. The Contract Documents examination report.
c. TAB plan.
d. Work schedule and Project-site access requirements.
e. Coordination and cooperation of trades and subcontractors.
f. Coordination of documentation and communication flow.
C. Certification of TAB Reports: Certify TAB field data reports. This certification includes the following:
1. Review field data reports to validate accuracy of data and to prepare certified TAB reports.
2. Certify that TAB team complied with approved TAB plan and the procedures specified and referenced in this Specification.
D. TAB Report Forms: Use standard forms from AABC's "National Standards for Testing and Balancing Heating, Ventilating, and Air Conditioning Systems." or NEBB's "Procedural Standards for Testing, Adjusting, and Balancing of Environmental Systems."
E. Instrumentation Calibration: Calibrate instruments at least every six months or more frequently if required by instrument manufacturer.
1. Keep an updated record of instrument calibration that indicates date of calibration and the name of party performing instrument calibration.
1.5 PROJECT CONDITIONS
A. Full Owner Occupancy: Owner will occupy the site and existing building during entire TAB period. Cooperate with Owner during TAB operations to minimize conflicts with Owner's operations.
1.6 COORDINATION
A. 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 TAB activities.
B. Notice: Provide seven days' advance notice for each test. Include scheduled test dates and times.
C. Perform TAB after leakage and pressure tests on air and water distribution systems have been satisfactorily completed.
1.7 WARRANTY
A. National Project Performance Guarantee: Provide a guarantee on AABC's "National Standards for Testing and Balancing Heating, Ventilating, and Air Conditioning Systems" forms stating that AABC will assist in completing requirements of the Contract Documents if TAB firm fails to comply with the Contract Documents. Guarantee includes the following provisions.
B. Special Guarantee: Provide a guarantee on NEBB forms stating that NEBB will assist in completing requirements of the Contract Documents if TAB firm fails to comply with the Contract Documents. Guarantee shall include the following provisions:
1. The certified TAB firm has tested and balanced systems according to the Contract Documents.
2. Systems are balanced to optimum performance capabilities within design and installation limits.
PART 2 - PRODUCTS (NOT APPLICABLE)
PART 3 - EXECUTION
3.1 EXAMINATION
A. Examine the Contract Documents to become familiar with Project requirements and to discover conditions in systems' designs that may preclude proper TAB of systems and equipment.
1. Verify that balancing devices are required by the Contract Documents. Verify that quantities and locations of these balancing devices are accessible and appropriate for effective balancing and for efficient system and equipment operation.
2. The TAB Firm shall review the Contract Documents and the Mechanical Contractor’s shop drawings to identify any additional balancing devices that are necessary to achieve a balanced system but not shown on the drawings. Furnish and install those additional balancing devices necessary to achieve a balanced system. Coordinate with the Mechanical Contractor to properly schedule this work. Failure to coordinate installation of these devices with the Mechanical Contractor will result in absorbing all costs associated with work of other trades that is affected by modification of building components and systems. All balancing devices and installations shall comply with other Division 15 sections.
B. Examine approved submittal data of HVAC systems and equipment.
C. Examine Project Record Documents described in Division 1 Section "Project Record Documents."
D. Examine design data, including HVAC system descriptions, statements of design assumptions for environmental conditions and systems' output, and statements of philosophies and assumptions about HVAC system and equipment controls.
E. Examine equipment performance data including pump curves. Relate performance data to Project conditions and requirements, including system effects that can create undesired or unpredicted conditions that cause reduced capacities in all or part of a system. Calculate system effect factors to reduce performance ratings of HVAC equipment when installed under conditions different from those presented when the equipment was performance tested at the factory.
F. Examine system and equipment installations to verify that they are complete and that testing, cleaning, adjusting, and commissioning specified in individual Sections have been performed.
G. Examine system and equipment test reports.
H. Examine HVAC system and equipment installations to verify that indicated balancing devices, such as test ports, gage cocks, thermometer wells, flow-control devices, balancing valves and fittings, and manual volume dampers, are properly installed, and that their locations are accessible and appropriate for effective balancing and for efficient system and equipment operation.
I. Examine systems for functional deficiencies that cannot be corrected by adjusting and balancing.
J. Examine HVAC equipment to ensure that clean filters have been installed, bearings are greased, belts are aligned and tight, and equipment with functioning controls is ready for operation.
K. Examine automatic temperature system components to verify the following: Dampers, valves, and other controlled devices are operated by the intended controller.
1. Dampers and valves are in the position indicated by the controller.
2. Thermostats are located to avoid adverse effects of sunlight, drafts, and cold walls.
3. Sensors are located to sense only the intended conditions.
4. Sequence of operation for control modes is according to the Contract Documents.
5. Controller set points are set at indicated values.
6. Interlocked systems are operating.
7. Changeover from heating to cooling mode occurs according to indicated values.
L. Report deficiencies discovered before and during performance of TAB procedures. Observe and record system reactions to changes in conditions. Record default set points if different from indicated values.
3.2 PREPARATION
A. Prepare a TAB plan that includes strategies and step-by-step procedures.
B. Complete system readiness checks and prepare system readiness reports. Verify the following:
1. Permanent electrical power wiring is complete.
2. Automatic temperature-control systems are operational.
3. Equipment and duct access doors are securely closed.
3.3 GENERAL PROCEDURES FOR TESTING AND BALANCING
A. Perform testing and balancing procedures on each system according to the procedures contained in AABC's "National Standards for Testing and Balancing Heating, Ventilating, and Air Conditioning Systems" or NEBB’s "Procedural Standards for Testing, Adjusting, and Balancing of Environmental Systems” and this Section.
B. 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 insulation Specifications for this Project.
C. Mark equipment and balancing device settings with paint or other suitable, permanent identification material, including damper-control positions, valve position indicators, fan-speed-control levers, and similar controls and devices, to show final settings.
D. Take and report testing and balancing measurements in inch-pound (IP) units.
3.4 PROCEDURES FOR MOTORS
A. Motors, 1/2 HP and Larger: Test at final balanced conditions and record the following data:
1. Manufacturer, model, and serial numbers.
2. Motor horsepower rating.
3. Motor rpm.
4. Efficiency rating.
5. Nameplate and measured voltage, each phase.
6. Nameplate and measured amperage, each phase.
7. Starter thermal-protection-element rating.
B. Motors Driven by Variable-Frequency Controllers: Test for proper operation at speeds varying from minimum to maximum. Test the manual bypass for the controller to prove proper operation. Record observations, including controller manufacturer, model and serial numbers, and nameplate data.
3.5 PROCEDURES FOR TEMPERATURE MEASUREMENTS
A. During TAB, report the need for adjustment in temperature regulation within the automatic temperature-control system.
B. Measure indoor wet- and dry-bulb temperatures every other hour for a period of two successive eight-hour days, in each separately controlled zone, to prove correctness of final temperature settings. Measure when the building or zone is occupied.
C. Measure outside-air, wet- and dry-bulb temperatures.
3.6 TOLERANCES
A. Set HVAC system airflow and water flow rates within the following tolerances:
1. Heating-Water Flow Rate: +5 to minus 5 percent.
2. Air Flow Rate: +5 to minus 5 percent. Adjust air flows to maintain relative room pressure requirements. Hazardous, corrosive and high moisture areas should always be set so that relative room pressure is negative in relationship to adjacent areas and rooms.
3.7 REPORTING
A. Initial Construction-Phase Report: Based on examination of the Contract Documents as specified in "Examination" Article, prepare a report on the adequacy of design for systems' balancing devices. Recommend changes and additions to systems' balancing devices to facilitate proper performance measuring and balancing. Recommend changes and additions to HVAC systems and general construction to allow access for performance measuring and balancing devices.
B. Status Reports: As Work progresses, prepare reports to describe completed procedures, procedures in progress, and scheduled procedures. Include a list of deficiencies and problems found in systems being tested and balanced. Prepare a separate report for each system and each building floor for systems serving multiple floors.
3.8 FINAL REPORT
A. General: Typewritten, or computer printout in letter-quality font, on standard bond paper, in three-ring binder, tabulated and divided into sections by tested and balanced systems.
B. Include a certification sheet in front of binder signed and sealed by the certified testing and balancing engineer.Include a list of instruments used for procedures, along with proof of calibration.
C. Final Report Contents: In addition to certified field report data, include the following:
1. Air Handler info and test data
2. Air coil info and test day – air flow and water flow
3. Pump curves.
4. Manufacturers' test data.
5. Field test reports prepared by system and equipment installers.
6. Other information relative to equipment performance, but do not include Shop Drawings and Product Data.
D. General Report Data: In addition to form titles and entries, include the following data in the final report, as applicable:
1. Title page.
2. Name and address of TAB firm.
3. Project name.
4. Project location.
5. Engineer's name and address.
6. Contractor's name and address.
7. Report date.
8. Signature of TAB firm who certifies the report.
9. Table of Contents with the total number of pages defined for each section of the report. Number each page in the report.
10. Summary of contents including the following:
11. Indicated versus final performance.
12. Notable characteristics of systems.
13. Description of system operation sequence if it varies from the Contract Documents.
14. Nomenclature sheets for each item of equipment.
15. Data for terminal units, including manufacturer, type size, and fittings.
16. Notes to explain why certain final data in the body of reports varies from indicated values.
E. System Diagrams: Include schematic layouts of air and hydronic distribution systems. Present each system with single-line diagram and include the following:
1. Air flow rates – air handling units, supply, exhaust and transfer fans.
2. Water flow rates - pumps, coils, hot water unit Heaters, cabinet unit heaters
3. Position of balancing devices.
4. Fan Test Data (Indicated and Actual Values):
a. Voltage at each connection.
b. Amperage for each phase.
c. Air flow rate in cfm
5. Pump Test Data (Indicated & Actual Values):
a. Voltage at each connections
b. Amperage for each phase
c. Dead Head discharge & suction pressures – (establishes curve)
d. Water Flow gpm including discharge and suction pressures.
e. Triple Duty Valve setpoints (as applicable).
3.9 INSPECTIONS
A. Initial Inspection:
1. After testing and balancing are complete, operate each system and randomly check measurements to verify that the system is operating according to the final test and balance readings documented in the Final Report.
2. Randomly check the following for each system:
a. Verify that balancing devices are marked with final balance position.
b. Note deviations to the Contract Documents in the Final Report.
B. Final Inspection:
1. After initial inspection is complete and evidence by random checks verifies that testing and balancing are complete and accurately documented in the final report, request that a final inspection be made by Owner.
2. TAB firm test and balance engineer shall conduct the inspection in the presence of Owner.
3. Owner shall randomly select measurements documented in the final report to be rechecked. The rechecking shall be limited to either 10 percent of the total measurements recorded, or the extent of measurements that can be accomplished in a normal 8-hour business day.
4. If the rechecks yield measurements that differ from the measurements documented in the final report by more than the tolerances allowed, the measurements shall be noted as "FAILED."
5. If the number of "FAILED" measurements is greater than 10 percent of the total measurements checked during the final inspection, the testing and balancing shall be considered incomplete and shall be rejected.
6. TAB firm shall recheck all measurements and make adjustments. Revise the final report and balancing device settings to include all changes and resubmit the final report.
7. Request a second final inspection. If the second final inspection also fails, Owner shall contract the services of another TAB firm to complete the testing and balancing in accordance with the Contract Documents and deduct the cost of the services from the final payment.
3.10 TEST ALL HVAC CONTROL SYSTEMS FOR PROPER OPERATION (HVAC CONTROL SYSTEM COMMISSIONING).
A. Test thermostats for proper operation.
B. Test all interlocks between equipment and control devices. Verify fan equipment operates and dampers open and close automatically as required. Verify Generator room dampers operate as required.
C. Verify proper operation of makeup air unit along with any associated interlocks room override thermostats, air quality sensors & timing functions as applicable.
D. Report any deficiencies in HVAC Control to HVAC Contractor and his Control Subcontractor for corrective action. Recheck for proper operation after corrections are made.
E. Provide summary of results of this control system checkout as part of tab report. State findings for each system checked – whether operation complies with sequence of operation or not and describe corrective action taken by HVAC contractor and results of retest.
3.11 ADDITIONAL TESTS
A. Within 90 days of completing TAB, perform additional testing and balancing to verify that balanced conditions are being maintained throughout and to correct unusual conditions.
B. Include additional tests which could be requested by the engineer as part of startup and system adjusting. These additional tests shall be included as part of the original project scope.
C. Seasonal Periods: If initial TAB procedures were not performed during near-peak summer and winter conditions, perform additional testing, inspecting, and adjusting during near-peak summer and winter conditions.
END OF SECTION
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