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23 05 12-6 Testing and Balancing Submittal, RESUBMIT
V Construction Corey Olmstead 18260 Ithaca Arthaus 1/26/21 VC Note: submittal detailing procedure only. TAB report (uncertified) to be submitted upon completion of Testing & Balancing. Out Of OfficeOut Of Office X D.D.2/1/21 Qualification are acceptable, resubmit with balancing data. Test and Balance Strategies and Plan Outline: The purpose of this outline is to submit a plan for the test and balancing on this project. Balancing is a systematic process to ensure that all heating, ventilation, and air conditioning building systems perform according to the specified design intent and the owner’s operational needs. We will review the drawings and walk through the site to verify that there are sufficient balancing dampers and valves, isolation dampers, and test ports installed to perform test and balance. Any deficiencies in design or installation that will adversely affect or preclude proper test and balance will be reported directly upon their discovery. We will review the construction document plans, specifications, and equipment submittals, as necessary, with contractors, manufacturer representatives, owners, architect representatives, and engineering representatives, as required, to sufficiently understand design intent for the heating, ventilation, and air conditioning systems. This includes previous discussions with the controls contractor to go over using his system to facilitate the balancing. A blank field checkout sheet for discrepancy logs is included in this plan. Final test report sheets are also included. This includes the field handwritten and final typed test report sheets for each piece of equipment to be tested, adjusted, and balanced with pertinent data cells of information to be collected. Markings will be made on the ductwork of damper handle locations after approval and acceptance of the system by the engineer of record, owner, and architect. The detailed step by step procedures for the test and balance are enclosed. Terminal flow calibration, diffuser proportioning, branch/submain proportioning, total flow calculations, rechecking, diversity issues, unexpected problems, solutions, and criteria for using air flow straighteners or relocating flow stations and sensors will be discussed, should these situations arise on either the air or water testing. The field balance forms and final balance report will list all air flow and water flow criteria. System design and actual measurements will be recorded as described in the test procedures. Formulas to be used are typically the fan laws and the pump laws. Total flow can be determined by the summation of terminals, totaling the hood readings, by traversing the main duct, plotting fan curves, or using flow stations. Pump curves, circuit setters, water flow stations, triple duty valves, pressure drops or temperature differentials can be used to determine total water flow. As there are many ways to determine total flow, it is the responsibility of my balance technician on site to determine the most accurate and practical method. Instruments to be used to take these measurements and their calibration certificates are included in this submittal. To ensure that both air and water side are operating at the lowest possible pressures, the lowest possible control set points will be discussed with the control contractor for input into the building automation system. The test and balance contractor will understand the outside air ventilation criteria as specified in the contract documents and details of how to measure airflow are included in the procedures and minimum outside air cubic feet per minute will be verified and set for each air handling unit as specified. Exhaust fan/ relief damper capacity, if specified, will be checked by steps outlined in the procedures. Building static pressure, if specified, can be checked with a Dwyer Instruments vaneometer or measured with a Shortridge Instruments air data meter. Procedures for exhaust fan testing and balancing are included in this submittal. Their actual cubic feet per minute listed will be used to verify their capacity. If room pressure differentials are specified they can be verified by use of a Dwyer Instruments vaneometer or Shortridge Instruments air data meter. Formal deficiency reports and field technician logs of discrepancies, deficient or uncompleted work by others, contract interpretation requests and lists of uncompleted tests will be hand written by the field test and balance technician on an as needed basis directly upon discovery of such. The scope will included the date, location, pump, air handling unit or device number, and a brief description of the situation. The distribution of the reports will be through the chain of command. Formal progress reports: As various phases are completed final test and balance reports will be issued with all deliberate speed after that particular phase is completed. AIR SYSTEM TESTING, ADJUSTING & BALANCING PROCEDURES 1 INTRODUCTION This section describes procedures for testing, adjust-ing and balancing (TAB) HVAC systems. Procedures in this section address the majority of systems com-monly installed. It is the responsibility of the NEBB CF or NEBB CP to determine appropriate procedures for systems not covered in this section. 2 PRELIMINARY SYSTEM PROCEDURES 2.1 PERFORMANCE PARAMETERS Each type of HVAC system is designed to meet a set of performance parameters. This usually includes maximum heating capacity, maximum cooling ca- pacity and ventilation e ectiveness. Prior to the TAB process, the CF should normally set up a system to its ‘full load’ condition (or maximum capacity). The full load condition presents the greatest challenge to a system’s capacity meeting its design airflow re- quirements. 2.2 LIMITATIONS Not all systems are covered in this section, only those most commonly installed. Confer with the engineer of record to establish the proper set up conditions for specific systems. 2.3 BASIC PROCEDURES The following TAB procedures are basic to all types of air systems: a)Verify that the construction team responsi- bilities for system installation and startup as discussed in Section 3 are complete. b)Record unit nameplate data as described in Section 6. c)Confirm that all items a ecting airflow of a duct system is ready for the TAB work, such as doors and windows closed, ceiling tiles (return air plenums) in place, transfer grilles in place, etc. d)Confirm that automatic control devices are complete, properly installed and the control system has been commissioned by others prior to starting the TAB work. e)Establish the conditions for design maximum system requirements. f)Verify that all dampers are open or set, all re- lated systems (supply, return, exhaust, etc.), are operating, motors are operating at or be- low full load amperage ratings, and rotation is correct. g)Positive and negative pressurization zones are to be identified at this time. 3 ESTABLISHING FAN TOTAL AIRFLOW 3.1 TOTAL AIRFLOW MEASUREMENT The most accurate and accepted field test of airflow is a Pitot tube or Airfoil traverse of the duct. Proce- dures for conducting a traverse are found in Section 6.In situations in which a traverse(s) is not available, the system airflow may be determined by alternate methods, such as anemometer or velocity grid tra- verses across coils and/or filters, or the summation of air outlet measurements. These alternative meth- ods are subject to a greater degree of error than duct traverses and are to be used with caution. 3.2 COMPARISON OF TOTAL AIRFLOW Additionally, if a traverse location is available, a com- parison of the total outlet airflow measurement with the traverse readings of the fan total airflow may as- sist in quantifying possible duct leakage. It is import- ant to note that di erences between total air outlet volume and traverse totals may be indicative of duct leakage, measurement errors, or incorrect area fac- tors. Accurate assessment of duct leakage requires a specific duct leakage test, which may or may not be outside the scope of TAB project specification. 3.3 USE OF FAN CURVES Fan curves can be used when other required data can be obtained, such as static pressure (SP), rotations per minute (rpm) and brake horsepower [bhp (W)]. However, technicians should be aware that System E ect and measurement errors might yield fi eld readings that are incompatible with fan and design system curves. 3.4 FAN SPEED ADJUSTMENT If the fan volume is not within plus or minus 10% of the design airflow requirement, adjust the drive of the fan to obtain the approximate required airflow. At the conclusion of all system balancing procedures, mea- sure and record the fan suction static pressure, fan discharge static pressure, amperage and air volume measurements. Confirm t hat t he f an m otor i s n ot operating in excess of its full load amperage rating. Care must be exercised when increasing fan speeds to avoid exceeding the maximum recommended rpm of the fan and the motor horsepower (W). (The motor power increases as the cube of the fan speed change.) When new systems do not perform as designed, new drives and motors may be required. Unless clearly specified in the contract documents, the responsibility for these items is outside the scope of the CF. 3.5 COMMON REFERENCE POINT When performing SP readings on fan systems, it is necessary to take the readings based on a common static reference point. 3.6 SUPPLY, RETURN, EXHAUST VOLUMES Using the methods outlined above, determine the volume of air being handled by the supply air fan, and return air fan if used. If a central exhaust fan system is used, also determine the airflow being handled by the exhaust fan. If several exhaust fans, such as pow- er roof ventilators are related to a particular supply air system, it generally is not necessary to measure the airflow of each such exhaust fan until after the supply air system is balanced. 3.7 100% OUTSIDE AIR CONDITION Verify the system test data with the supply air and return air fans in the 100% outside air (OA) and ex- haust air (EA) mode. Use caution as ambient condi- tions may adversely affect system operation. 4 AIR SYSTEM BALANCING PROCEDURES Balancing air systems may be accomplished in vari-ous ways.Regardless of the method, the objectives remain the same and the system will be considered balanced in accordance with this edition of NEBB Procedural Standard for Test-ing, Adjusting and Balancing of Environmental System (Procedural Standard) when the following conditions are satisfied: a)All measured airflow quantities are within ±10% of the design airflow quantities unless there are reasons beyond the control of the CF. If the total available air is above or be- low design and cannot be decreased or in- creased, the air distribution system shall be proportionally balanced to within 10% of the available total. Deficiencies shall be noted in the TAB Report Summary. b)There is at least one path with fully open dampers from the fan to an air inlet or out- let. Additionally, if a system contains branch dampers, there will be at least one wide-open path downstream of every adjusted branch damper. HYDRONIC SYSTEM TESTING, ADJUSTING & BALANCING PROCEDURES 1 INTRODUCTION This section describes procedures necessary for testing, adjusting and balancing (TAB) of commonly installed HVAC systems. It is the responsibility of the NEBB Certified TAB Firm (CF) or NEBB Certified TAB Professional (CP) to determine appropriate proce-dures for systems not covered in this section. 2 PRELIMINARY SYSTEM PROCEDURES 2.1 Each type of HVAC system is designed to meet a set of performance parameters. This usually includes maximum heating capacity, maximum cooling ca- pacity and ventilation e ectiveness. Prior to the TAB process, the CF should normally set up a system to its ‘full load’ condition (or maximum capacity). The full load condition presents the greatest challenge to a system’s capacity meeting its design airflow re- quirements. 2.2 Not all systems are covered in this section, only those most commonly installed. Confer with the EOR to establish the proper set up conditions for specific systems. 2.3 The following TAB procedures are basic to all types of hydronic systems: a)Verify that the construction team responsi- bilities for system installation and startup as discussed in Section 3 are complete. b)Confirm that every item a ecting the hy- dronic flow in a piping system is ready for the TAB work, i.e. pumps started and operating, piping systems flushed, vented, chemical treatment complete, air vents installed and operating. Startup strainer screens removed and replaced with final strainer screens. Ex- pansion tank properly installed and system properly filled to design pressure. c)Prepare and submit, if required, the TAB plan that includes specific hydronic procedures to be implemented. d)Prepare TAB forms in compliance with Sec- tion 5 of this edition of Procedural Standard and the project’s drawings and specifications. e)Confirm that automatic control system is complete and available for use in completing TAB operations. f)Simulate the conditions for design maximum system requirements. g)Verify that all valves are open or set, all relat- ed systems are operating, motors are oper- ating at or below full load amperage ratings, and pump rotation is correct. 3 HYDRONIC SYSTEM MEASUREMENT METHODS 3.1 BASIC FLOW MEASUREMENT METHODS The appropriate techniques for flow measurement of hydronic systems are to be determined by review- ing the system(s) to be tested. There are six basic methods available for measuring the flow quantity in a piping system: 1.Flow meters or flow fittings 2.Calibrated balancing valves 3.Pump curves 4.Equipment pressure loss 5.Heat transfer method 6.Ultrasonic Flowmeter It is preferable to balance hydronic systems by the use of calibrated flow measuring devices. Flow measurement is accomplished by the use of dif- ferential pressure meters and calibrated balancing valves, venturis and/or ultrasonic flow meters. Bal- ancing flow measurement eliminates compound- ing errors introduced by the temperature differ- ence or equipment pressure drop procedures. This measurement approach also allows the pump to be matched to the actual system requirements. Proper instrumentation and good pre-planning is needed. 3.2 CALIBRATED FLOW MEASURING DEVICES Calibrated flow measuring devices are the preferred method of flow measurement. The CF will verify that installation of the calibrated flow measuring devices is in accordance with recommended practices given by the manufacturer. Calibrated flow measuring de- vices include orifice plates, venturis, Pitot tubes, tur- bine meters, ultrasonic meters, etc. Note: Verify that the pressure units of the di erential pressure gauge and the pressure units found on the flow charts provided by the manufacturer are iden- tical. If pressure units are not the same (i.e. psi, in. w.g., ft. w.g., Pa, kPa, mm, m /h), pressure conver- sions will be required. 3.3 CALIBRATED BALANCING VALVES The three types of calibrated balancing valves are: self-adjusting, adjustable orifice, and fi xed orifice valves. Self-Adjusting Valves A self-adjusting valve/flow sensing device utilizes internal mechanisms that constantly change internal orifice openings to compensate for varying system di erential pressures while maintaining a preset flow rate. No external adjustment is available with this device. Pressure taps allow for measurement of valve di erential pressure which is an indirect indication of system flow. The CF will verify the valve flow rating from the data tag, and verify by di erential pressure measure- ments, if available, that the pressure drop across the valve is within the control range of the valve. Adjustable Orifice Valves Some calibrated balancing valves are adjustable ori- fice devices. A chart or graph, provided by the valve manufacturer, indicates actual flow rates at various valve positions and di erential pressures. Measure- ment of the actual flow requires knowledge of the valve position, valve size, and pressure di erential of the valve. Fixed Orifice Valves Some calibrated balancing valves are fixed orifice de- vices. A chart or graph, provided by the valve man- ufacturer, indicates actual flow rates at various valve positions and di erential pressures. Measurement of the actual flow requires knowledge of valve size, and pressure differential of the valve. 3.4 PUMP CURVE METHOD Actual system flow can be determined with the manufacturer’s pump curve provided with the pump or provided as part of the certified submittal data. If a certified curve is not available, pump flow may be approximated by a catalog pump curve. Pump pres- sure readings shall be taken at the same test loca- tions used by the manufacturer. The pump impeller size is verified by measurement of the pump shut-o (no flow) di erential head. The shut-o head value is compared to pump curve data to determine the size of the pump impeller. After opening the pump discharge valve, the pump total head is determined by calculating the di erence be- tween the pump discharge pressure and pump suc- tion pressure. Using the total head, in appropriate units, determine the pump water flow from the cor- rected pump curve established previously. Verify the pump curve data with data from flow meters and/or calibrated balancing valves. 3.5 EQUIPMENT PRESSURE LOSS METHOD System flow rates may be calculated by using the HVAC equipment pressure loss, provided that certi- fied data is obtained from the equipment manufac- Hydronic System Testing, Adjusting and Balance Procedures turer indicating rated flow and pressure losses; and provided that there is an accurate means for deter- mining the actual equipment pressure losses. Equip- ment pressure readings shall be taken at similar test locations used by the manufacturer. Inaccurate mea- surements will result if dirt, debris, or scaling is pres- ent. Measurements will also be inaccurate if the test ports are placed such that the measured pressures include pressure drops across valves, elbows, tees, etc. If available, verify the equipment pressure loss data with data from flow meters and/or calibrated balancing valves. When the design criteria of the equipment and the pressure loss are known, the flow rate may be calcu- lated by using the pump affinity laws. 3.6 HEAT TRANSFER METHOD Approximate flow rates may be established at heat- ing and cooling terminals by using both air and hy- dronic measured heat transfer data. 4 HYDRONIC SYSTEM PROCEDURES Balancing hydronic systems may be accomplished in various ways. Regardless of the method, the objectives remain the same and the system will be considered balanced in accordance with this edition of NEBB Procedural Standard for Testing, Adjusting and Balancing of Environmental System (Procedural Stan-dard) when the following conditions are satisfied: 1)All measured hydronic flow quantities are within ±10% of the design flow quantities un- less there are reasons beyond the control of the CF. (Known factors in system deficiencies will be noted in the TAB report summary.) 2)There is at least one path with fully open balancing valves from the pump to a termi- nal device. Additionally, if a system contains branch-balancing valves, there will be at least one wide-open path downstream of ev- ery adjusted branch-balancing valve. DESIGN DESIGN DESIGN REMARKS: TAB 2005 © Copyright, NEBB 2005 Page of FAN TEST REPORT Motor Make/Style Motor H.P./RPM/Frame (W) Motor Sheave Make/Model FAN NO. Motor Sheave Diam./Bore Volts/Phase/Hertz F.L. Amps/S.F. FAN DATA Model Number Serial Number Type/Class Location Service Manufacturer CFM Fan Sheave Make Fan Sheave Diam./Bore No. Belts/Make/Size Sheave CL Distance FAN NO. FAN NO. PROJECT: TEST DATA ACTUAL ACTUAL ACTUAL NEBB Certification Seal Report Not Valid Unless Cover Sheet Stamped With READINGS BY: National Environmental Balancing Bureau TEST DATE: Amperage T1 T2 T3 Static Pressure In/Out Fan RPM/Speed Hertz / Operating Setpoint T3 - T1 Voltage T1 - T2 T2 - T3 Total Static Pressure PROJECT: SYSTEM: OUTLET MANUFACTURER: — TEST APPARATUS: AREA\RM # SERVED NO.TYPE SIZE AK VEL CFM CFM CFM CFM CFM CFM CFM REMARKS: TEST DATE: READINGS BY: TAB 2005 © Copyright, NEBB 2005 Page ofNEBB Certification Seal DESIGNOUTLET PRELIMINARY FINAL National Environmental Balancing Bureau Report Not Valid Unless Cover Sheet Stamped With AIR OUTLET REMARKS TEST REPORT psi Discharge Suction REMARKS: © Copyright, NEBB 2005 Page of Voltage Amperage Pump Differential TEST DATE: READINGS BY: NEBB Certification SealTAB 2005 National Environmental Balancing Bureau Report Not Valid Unless Cover Sheet Stamped With PUMP TEST REPORT FOR PROJECT: BALANCE VALVE / TRIPLE DUTY VALVE MECHANICAL MECHANICAL MECHANICAL MECHANICAL PUMP # PUMP # PUMP # PUMP # GPM Volts/Phase/Hertz F.L. Amps/S.F. Seal Type Size Setting Pressure Diff. Ft. Manufacturer Model Type Manufacturer Model Number Serial Number Location Service Impeller Diam. Motor Mfg./Frame Motor HP/RPM GPM/Head Req. NPSH DATA Pump RPM HTz If There is a Freq. Drive Pump Off Pressure If there are gauges across the pump Head measured in feet of water, Pressure measured in psi (pounds per square inch)DESIGN ACTUAL NEW YORK TECHNOLOGIES Date:WATER METERING DEVICE - TEST SHEETPage:Project Name: Project Location: DesignField TestNo.Location/Rm #ServiceSizeModelGPMSettingReading Ft.GPM123456789101112131415161718192021222324251 of GPM = Gallons per minute, PSI = Pounds per square inch, PSID = Pounds per square inch differential, FT = Feet of water pressure FAX COVER SHEET/DISCREPANCY LOG NEW YORK TECHNOLOGIES CORPORATION HVAC TEST AND BALANCING N.E.B.B. CERTIFIED 3737 NEW COURT AVENUE SYRACUSE, NEW YORK 13206 PHONE: 315 - 432-1917 FAX: 315 – 432-5627 DATE: PLEASE DELIVER THE FOLLOWING PAGE(S) (INCLUDING COVER) TO: COMPANY: FROM: SUBJECT: COMMENTS / SPECIAL INSTRUCTIONS: THANK YOU