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OC Sportsplex Pool HVAC Unit Replacement <br />PDC Project 23022 Testing,Adjusting,and Balancing for <br />HVAC 23 05 93 - 7 <br />cooling,to the heating mode,and back to cooling.Record and report the heating coil leaving <br />air temperature when the ATU is in the maximum heating mode. <br />P.The TAB report shall indicate the critical VAV box and how the static pressure set point was <br />estalished. <br />3.08 DUCTWORK LEAKAGE CRITERIA: <br />A.The TAB contractor shall be responsible for conducting and recording ALL duct leakage tests. <br />B.All transverse joints and longitudinal seams shall conform to SMACNA’s Class A sealing <br />requirements as defined in the SMACNA Manual. <br />C.Ductwork Sealing:As a minimum standard,ductwork and plenums shall be sealed in accordance <br />with Table 6.2.4.3A of ASHRAE Standard 90.1 (as required to meet the requirements of Section <br />6.2.4.4 SMACNA Duct Leakage Test Procedures). <br />D.Ductwork constructed to 3"w.g.pressure class (positive or negative)or higher shall be leak-tested <br />according to the SMACNA HVAC Air Leakage Test Manual.All sections shall be tested,unless <br />otherwise noted. <br />E.The Test Pressure for each system shall be equal to the construction pressure class the respective <br />duct system is constructed to. <br />F.Maximum permitted duct leakage shall be: <br />1.Lmax =CL x Test Pressure “P”raised to the 0.65 power where Lmax is maximum permitted <br />leakage in CFM/100 sq.ft.duct surface area <br />2.CL is duct leakage class in cfm/100 sq.ft.at 1-inch w.c.,which shall be <br />a.“6”for rectangular sheetmetal,rectangular fibrous ducts,and round flexible ducts. <br />b.“3”for round/flat oval sheetmetal or fibrous glass ducts. <br />3.P is test pressure,equal to the duct construction pressure class rating in inches w.c. <br />G.Duct Air Leakage Testing (DALT): <br />1.Installed ductwork shall be tested prior to installation of access doors,take-offs etc. <br />2.All testing shall be witnessed by the engineer or owner’s representative.Contractor shall give <br />the engineer or owner’s representative 72 hours’notice prior to testing. <br />3.The testing shall be performed as follows: <br />a.Perform testing in accordance with SMACNA HVAC Air Duct Leakage Test Manual. <br />b.Use a certified orifice tube for measuring the leakage. <br />c.Define section of system to be tested and blank off. <br />d.Determine the percentage of the system being tested. <br />e.Using that percentage,determine the allowable leakage (CFM)for that section being <br />used. <br />f.Pressurize to operating pressure and repair any significant or audible leaks. <br />g.Re-pressurize and measure leakage. <br />h.Repeat steps 6 and 7 until the leakage is less than the allowable defined in step 5. <br />3.09 WATER SYSTEM PROCEDURE <br />A.Adjust water systems to provide design quantities. <br />B.Use calibrated Venturi tubes,orifices,or other metered fittings and pressure gages to determine <br />flow rates for system balance. Where flow metering devices are not installed,base flow balance <br />on temperature difference across various heat transfer elements in the system. <br />C.Adjust systems to provide specified pressure drops and flows through heat transfer elements prior <br />to thermal testing. Perform balancing by measurement of temperature differential in conjunction <br />with air balancing. <br />D.Effect system balance with automatic control valves fully open to heat transfer elements. <br />E.Effect adjustment of water distribution systems by means of balancing cocks,valves,and fittings. <br /> Do not use service or shut-off valves for balancing unless indexed for balance point. <br />Docusign Envelope ID: D4F3B98E-0756-4A0C-A3AD-05AA32D39F1C