B. ASHRAE 1991 HVAC Applications Handbook: Chapter 34--Testing, Adjusting and Balancing.

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1 PART 1 GENERAL 1.1 RELATED DOCUMENTS SECTION TESTING, ADJUSTING, AND BALANCING A. Drawings and general provisions of Contract, including General and Supplementary Conditions and Division 1 Specification sections, apply to work of this section. 1.2 REFERENCE STANDARDS A. ASHRAE-Standard Practices for Measurement, Testing, Adjusting, and Balancing of Building Heating, Ventilation, Air Conditioning, and Refrigeration Systems. B. ASHRAE 1991 HVAC Applications Handbook: Chapter 34--Testing, Adjusting and Balancing. C. AABC--National Standards for Total System Balance. D. NEBB--Procedural Standards for Testing, Balancing and Adjusting of Environmental Systems. E. SMACNA--HVAC Systems--Testing, Adjusting and Balancing. F. Sheet Metal Industry--Testing, Adjusting, Balancing Bureau (TABB) Certified Technician Standards, Procedures and Specifications. 1.3 DESCRIPTION A. Provide total mechanical systems testing, adjusting and balancing. Requirements include the balance of air distribution, equipment adjustments to provide design quantities indicated on the drawings, and electrical measurement and verification of performance of all equipment. B. Test, adjust and balance all air systems so that each room, piece of equipment or terminal device is using the quantities indicated on the drawings and in the specifications. 1.4 SUMMARY A. This Section specifies the requirements and procedures for total mechanical systems testing, adjusting, and balancing. Requirements include measurement and establishment of the fluid quantities of the mechanical systems as required to meet design specifications, and recording and reporting the results. B. Test, adjust, and balance the following mechanical systems: 1. Supply air systems. 2. Return air systems. 3. Exhaust air systems. TESTING, ADJUSTING, AND BALANCING

2 1.5 QUALITY ASSURANCE A. Test and Balance Engineer's Qualifications: Must have at least 3-years of successful testing, adjusting, and balancing experience on projects with testing and balancing requirements similar to those required for this project. B. Agency Qualifications: 1. Employ the services of an independent testing, adjusting, and balancing agency meeting the qualifications specified below, to be the single source of responsibility to test, adjust, and balance the building mechanical systems identified above, to produce the design objectives. Services shall include checking installations for conformity to design, measurement and establishment of the fluid quantities of the mechanical systems as required to meet design specifications, and recording and reporting the results. 2. The independent testing, adjusting, and balancing agency certified by National Environmental Balancing Bureau (NEBB) or by the Associated Air Balance Council (AABC) in those testing and balancing disciplines required for this project,. C. Codes and Standards: 1. NEBB: "Procedural Standards for Testing, Adjusting, and Balancing of Environmental Systems." 2. AABC: "National Standards for Total System Balance". 3. American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE): ASHRAE Handbook, 1999 HVAC Applications Volume, Chapter 36, Testing, Adjusting, and Balancing. 1.6 SUBMITTALS A. Agency Data: 1. Submit proof that the proposed testing, adjusting, and balancing agency meets the qualifications specified. B. Engineer and Technicians Data: 1. Submit proof that the proposed testing, adjusting, and balancing agency meets the qualifications specified. C. Procedures and Agenda: Submit a synopsis of the testing, adjusting, and balancing procedures and agenda proposed to be used for this project. D. Sample Forms: Submit sample forms, if other than those standard forms prepared by the Associated Air Balance Council (AABC) or National Environmental Balancing Bureau (NEBB) are proposed. E. Certified Reports: Submit testing, adjusting, and balancing reports bearing the seal and signature of the Test and Balance Engineer. The reports shall be certified proof that the systems have been tested, adjusted, and balanced in accordance with the referenced standards; are an accurate representation of how the systems have been installed; are a true representation of how the systems are operating at the completion of the testing, adjusting, and balancing procedures; and are an accurate record of all final quantities measured, to establish normal operating values of the systems. F. Submission: Submit three (3) complete sets of reports. If information is incomplete or further testing, adjusting and balancing is deemed necessary, resubmit three (3) final complete sets. TESTING, ADJUSTING, AND BALANCING

3 G. Report Format and Contents: 1. Format: Bind report forms in three-ring binders or portfolio binders. Label edge and binder front cover with label identifying project name, project number and descriptive title of contents. Divide the contents of the report into the below listed divisions, separated by divider tabs: a. General Information (title page and instrument list). b. Summary. c. Air Systems. 2. Title Page: a. Company name. b. Company address. c. Company telephone number. d. Name, signature, and registration number of each technician. e. Project name. f. Project location. g. Project Architect. h. Project Engineer. i. Project Contractor. j. Date of report. k. Balancing methodology (Ratio or Herman Method). 3. Instrument List: a. Instrument. b. Manufacturer. c. Model. d. Serial number. e. Range. f. Calibration histories. 4. Summary page(s) to include: a. Provide sheet describing mechanical system deficiencies. b. Describe objectionable noise or drafts found during testing, adjusting and balancing. 5. The remainder of the report shall contain the appropriate forms for each respective item and system. Fill out forms completely. Indicate on form when information cannot be obtained or is not applicable. 6. For air systems, the forms shall, at a minimum, include: a. Names and initials of personnel performing the balancing (on each form). b. Dates balancing were performed. (on each form) c. Weather conditions at the time of the test (especially temperature). d. All motor rated data: voltages, amps, RPM, HP, manufacturer, starter and overload protective device sizes. e. All motor operating data (before and after adjustments) voltages, amps, RPM, HP, BHP, and sheave size/rating and manufacturer. f. All fan data (design and operating): supply and return CFM, operating static pressures (suction, discharge, and fan static), fan sheave, belt size, fan RPM. g. All drive changes necessitated to obtain design capacities. h. List actual minimum outside air volumes measured for each system and the corresponding control setpoint. i. All supply and return air outlet CFM readings. Include velocity measurements and A K factors where applicable. Include initial and final CFM readings at each box. j. Heating and cooling coil entering and leaving air temperatures during test (as a reference). 7. Any deficiencies that could not be resolved should be provided in writing and explanation of the problem provided. TESTING, ADJUSTING, AND BALANCING

4 1.7 PROJECT CONDITIONS A. Systems Operation: Systems shall be fully operational prior to beginning procedures. PART 2 PRODUCTS Not Used PART 3 EXECUTION 3.1 PRELIMINARY PROCEDURES FOR AIR SYSTEM BALANCING A. Before operating the system, perform these steps: 1. Obtain design drawings and specifications and become thoroughly acquainted with the design intent. 2. Obtain copies of approved shop drawings of all air handling equipment, outlets (supply, return, and exhaust) and temperature control diagrams. 3. Compare design to installed equipment and field installations. 4. Walk the system from the system air handling equipment to terminal units to determine variations of installation from design. 5. Check filters for cleanliness. 6. Check dampers for correct and locked position, and temperature control for completeness of installation before starting fans. 7. Prepare report test sheets for both fans and outlets. Obtain manufacturer's outlet factors and recommended procedures for testing. Prepare a summation of required outlet volumes to permit a crosscheck with required fan volumes. 8. Determine best locations in main and branch ductwork for most accurate duct traverses. 9. Place outlet dampers in the full open position. 10. Prepare schematic diagrams of system "as-built" ductwork and piping layouts to facilitate reporting. 11. Lubricate all motors and bearings. 12. Check fan belt tension. 13. Check fan rotation. 14. Report to Architect/Engineer any defects or deficiencies noted during performance of services. 15. Promptly report abnormal conditions in mechanical systems or conditions, which prevent system balance. 16. Beginning of work means acceptance of existing conditions. 3.2 MEASUREMENTS A. Provide all required instrumentation to obtain proper measurements, calibrated to the tolerances specified in the referenced standards. Instruments shall be properly maintained and protected against damage. B. Provide instruments meeting the specifications of the referenced standards. C. Use only those instruments which have the maximum field measuring accuracy and are best suited to the function being measured. D. Apply instrument as recommended by the manufacturer. E. Use instruments with minimum scale and maximum subdivisions and with scale ranges proper for the value being measured. TESTING, ADJUSTING, AND BALANCING

5 F. When averaging values, take a sufficient quantity of readings which will result in a repeatability error of less than 5 percent. When measuring a single point, repeat readings until 2 consecutive identical values are obtained. G. Take all reading with the eye at the level of the indicated value to prevent parallax. H. Use pulsation dampeners where necessary to eliminate error involved in estimating average of rapidly fluctuation readings. I. Take measurements in the system where best suited to the task. 3.3 PERFORMING TESTING, ADJUSTING, AND BALANCING ON AIR SYSTEMS A. Perform testing, adjusting and balancing procedures on each system identified in drawing, in accordance with the detailed procedures outlined in the referenced standards except as may be modified below. B. In areas containing ceilings, remove ceiling tile to accomplish balancing work. Replace tile when work is complete and provide new tile for any tile that was damaged by this procedure. If the ceiling construction is such that access panels are required for the work of this section and the panels have not been provided, inform the owner representative. C. In air systems employing filters, blank off sufficient filter area to simulate a pressure drop that is midway between that of a clean filter and that of a dirty filter. D. Test and Balance Contractor shall set outlets/diffusers flow rate (volume) by adjusting dampers installed in the ductwork. Do not use volume dampers that are integral with the outlets/diffusers to set outlet/diffuser volume. E. Make air quantity measurements in ducts by Pitot tube traverse of entire cross sectional area of duct. F. Provide fan and motor drive sheave adjustments necessary to obtain design performance. G. Measure and record static air pressure conditions across fans, coils and filters. Indicate in report if cooling coil measurements were made on a wet or dry coil and if filter measurements were made on a clean or dirty filter. H. Adjust outside air, return air and relief air dampers for design conditions at both the minimum and maximum settings and record both sets of data (and test methodology). If necessary, Test and Balance Contractor should return when an adequate temperature difference between the return air and outside air temperatures exists in order to determine minimum outside air damper position. I. Final air system measurements to be within the following range (unless directed otherwise by Engineer) of the specified CFM: Fans Supply grilles, registers, diffusers Return/exhaust grilles, registers -5% to +10% of design value -10% to +10% of design value -10% to +10% of design value J. Leave systems in proper working order by replacing belt guards, closing access doors and electrical boxes, and restoring temperature controls to normal operating settings. TESTING, ADJUSTING, AND BALANCING

6 K. Cut insulation, ductwork, and piping for installation of test probes to the minimum extent necessary to allow adequate performance of procedures. L. Patch insulation, ductwork, and housings, using materials identical to those removed. M. Seal ducts and piping, and test for and repair leaks. N. Seal insulation to re-establish integrity of the vapor barrier. O. Mark equipment settings, including damper control positions, valve indicators, fan speed control levers, and similar controls and devices, to show final settings. Mark with paint or other suitable, permanent identification materials. P. Retest, adjust, and balance systems subsequent to significant system modifications, and resubmit test results. 3.4 RESPONSIBILITIES OF THE MECHANICAL CONTRACTOR A. The mechanical contractor shall complete the installation and start all HVAC systems to ensure they are working properly, and shall perform all other items as described hereinafter to assist the balancing agency in performing the testing and balancing of the HVAC systems. B. Air Distribution Systems: 1. Verify installation for conformity to design. 2. Ensure that all supply, return, and exhaust ducts are installed in such a manner that maximum allowable leakage rates as required by specifications are not exceeded. 3. Ensure that all volume, splitter, extractor, and fire dampers are properly located and functional. Dampers serving requirements of minimum and maximum outside, return, relief, and exhaust air shall provide tight closure and full opening, with a smooth and free operation. 4. Verify that all supply, return, exhaust, and transfer grilles; registers and diffusers are installed and operational. 5. Ensure that air-handling systems, units, and associated apparatus, such as heating and cooling coils, filter sections, access doors, etc., are blanked and/or sealed to eliminate excessive bypass or leakage of air. 6. Lubricating all motors and bearings. 7. Ensure that all fans (supply, return, relief, and exhaust) are operating and free of vibration. All fans and drives shall be checked for proper fan rotation and belt tension. Overload protection shall be of proper size and rating. A record of motor current and voltage shall be made to verify that the motors do not exceed nameplate rating. 8. Make any necessary changes to the sheaves, belts, and dampers, as required by the balancing agency, at no additional cost to the Owner. 9. Install clean filters. 3.5 RESPONSIBILITIES OF THE TEMPERATURE CONTROL CONTRACTOR TESTING, ADJUSTING, AND BALANCING

7 A. The temperature-control contractor shall complete the installation of the temperature control system, and operate and test all controls systems to ensure they are functioning properly as designed. The temperature control contractor shall assist the balancing agency in testing and balancing the HVAC systems, as described hereinafter. 1. Verify that all control components are installed in accordance with project requirements and are functional, including all electrical interlocks, damper sequences, air and water reset, and fire and freeze stats. 2. Verify that all controlling instruments are calibrated and set for design operating conditions. 3. Calibrate room thermostats after installation, and before the thermostat control verification tests are performed. The balancing agency shall prove the accuracy of final settings by taking temperature readings. The readings shall be in a typical conditioned space for each separately controlled zone. 4. The temperature-control contractor shall allow sufficient time in the project to provide assistance and instruction to the balancing agency in the proper use and setting of control components such as but not limited to, computers, static pressure controllers, or any other device that may need set points changed so that the testing and balancing work can be performed. END OF SECTION TESTING, ADJUSTING, AND BALANCING