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DocuSign Envelope ID: B94F2D40-3B3C-47A7-86C2-6F1 B4F92C62C <br /> Orange County Emergency Services Building Construction Documents <br /> K. Seal insulation to re-establish integrity of vapor barrier. <br /> L. Retest, adjust, and balance systems subsequent to significant system modifications and resubmit <br /> test results. <br /> 3.06 AIR SYSTEM PROCEDURE <br /> A. Adjust air handling and distribution systems to provide required or design supply, return, and <br /> exhaust air quantities at site altitude. <br /> B. Test, adjust, and balance the air systems before the hydronic systems. <br /> C. Make air quantity measurements in ducts by Pitot tube traverse of entire cross sectional area of <br /> duct. <br /> D. Measure air quantities at air inlets and outlets. <br /> E. Adjust distribution system to obtain uniform space temperatures free from objectionable drafts and <br /> noise. This includes adjusting the deflection of all diffuser and grilles. <br /> F. Use volume control devices to regulate air quantities only to extent that adjustments do not create <br /> objectionable air motion or sound levels. Effect volume control by duct internal devices such as <br /> dampers and splitters. <br /> G. Vary total system air quantities by adjustment of fan speeds. Provide drive changes required. Vary <br /> branch air quantities by damper regulation. <br /> H. Measure static air pressure conditions on air supply units, including filter and coil pressure drops, <br /> and total pressure across the fan. Make allowances for 50 percent loading of filters. <br /> I. Coordinate with Controls Contractor on adjusting static pressure setpoints of VAV systems and <br /> differential pressure setpoints of VFD controlled pumps. <br /> J. Adjust outside air automatic dampers, outside air, return air, and exhaust dampers for design <br /> conditions. <br /> K. Measure temperature conditions across outside air, return air, and exhaust dampers to check <br /> leakage. <br /> L. Where modulating dampers are provided, take measurements and balance at extreme conditions. <br /> Balance variable volume systems at maximum air flow rate, full cooling, and at minimum air flow <br /> rate, full heating. <br /> M. Measure building static pressure and adjust supply, return, and exhaust air systems to provide <br /> required relationship between each to maintain approximately 0.05 inches positive static pressure <br /> near the building entries. <br /> N. For variable air volume system powered units set volume controller to air flow setting indicated. <br /> Confirm connections properly made and confirm proper operation for automatic variable air volume <br /> temperature control. <br /> 3.07 DUCTWORK LEAKAGE CRITERIA: <br /> A. All transverse joints and longitudinal seams shall conform to SMACNA's Class A sealing <br /> requirements as defined in the SMACNA Manual. <br /> B. 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 /> C. Prove tightness of duct construction by operating air handling equipment and physically verifying <br /> absence of any air leakage, both audibly and manually. Repair as needed to achieve minimal <br /> leakage. Examine every joint and verify leak tight. If further testing is needed to resolve duct <br /> leakage problems, particularly as related to sound criteria, comply with procedure outline in 1985 <br /> (or current edition)of SMACNA HVAC Air Duct Leakage Test Manual. <br /> D. All DOAS unit ductwork shall be leak-tested according to the SMACNA HVAC Air Leakage Test <br /> Manual. All sections shall be tested, unless otherwise noted. <br /> E. 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 /> PDC Project 18102 TESTING, ADJUSTING, AND 23 05 93-4 <br /> 12/17/2018 BALANCING FOR HVAC <br />