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DocuSign Envelope ID: 9826C043- 4C32- 49CD- A4CC- DC28ABAB7CE7 <br />3.5 <br />A. <br />B. <br />C. <br />D. <br />E. <br />3.6 <br />A. <br />B. <br />Ar <br />C <br />SECTION 238000 — TEST AND BALANCE <br />Witness start -up and tests for all major HVAC equipment. Include copies of test reports, including <br />manufacturer's start -up check lists included in manufacturer's installation instructions, in the Test - <br />and- Balance report. <br />GENERAL PROCEDURES FOR BALANCING AIR SYSTEMS <br />Prepare test reports for both fans and outlets. Obtain manufacturer's outlet factors and <br />recommended testing procedures. Crosscheck the summation of required outlet volumes with <br />required fan volumes. <br />Prepare schematic diagrams of systems' "as- built" duct layouts. <br />For variable- air - volume systems, develop a plan to simulate diversity. <br />Determine the best locations in main and branch ducts for accurate duct airflow measurements. <br />Check airflow patterns from the outside -air louvers and dampers and the return- and exhaust -air <br />dampers, through the supply -fan discharge and mixing dampers. <br />Locate start-stop and disconnect switches, electrical interlocks, and motor starters. <br />Verify that motor starters are equipped with properly sized thermal protection. <br />Check dampers for proper position to achieve desired airflow path. <br />Check for airflow blockages. <br />Check condensate drains for proper connections, trap depth, and functioning. <br />Check for proper sealing of air - handling unit components. <br />Check for proper sealing of air duct system. <br />PROCEDURES FOR CONSTANT - VOLUME AIR SYSTEMS <br />Adjust fans to deliver total indicated airflows within the maximum allowable fan speed listed by fan <br />manufacturer. <br />1. Measure fan static pressures to determine actual static pressure as follows: <br />a. Measure outlet static pressure as far downstream from the fan as practicable and <br />upstream from restrictions in ducts such as elbows and transitions. <br />b. Measure static pressure directly at the fan outlet or through the flexible connection. <br />C. Measure inlet static pressure of single -inlet fans in the inlet duct as near the fan as <br />possible, upstream from flexible connection and downstream from duct restrictions. <br />d. Measure inlet static pressure of double -inlet fans through the wall of the plenum that <br />houses the fan. <br />2. Measure static pressure across each component that makes up an air - handling unit, rooftop <br />unit, and other air - handling and - treating equipment. <br />a. Simulate dirty filter operation and record the point at which maintenance personnel <br />must change filters. <br />3. Measure static pressures entering and leaving other devices such as sound traps, heat <br />recovery equipment, and air washers, under final balanced conditions. <br />4. Compare design data with installed conditions to determine variations in design static <br />pressures versus actual static pressures. Compare actual system effect factors with <br />calculated system effect factors to identify where variations occur. Recommend corrective <br />action to align design and actual conditions. <br />5. Make required adjustments to pulley sizes, motor sizes, and electrical connections to <br />accommodate fan -speed changes. <br />6. Do not make fan -speed adjustments that result in motor overload. Consult equipment <br />manufacturers about fan -speed safety factors. Modulate dampers and measure fan -motor <br />amperage to ensure that no overload will occur. Measure amperage in full cooling, full <br />heating, economizer, and any other operating modes to determine the maximum required <br />brake horsepower. <br />Adjust volume dampers for main duct, submain ducts, and major branch ducts to indicated airflows <br />within specified tolerances. <br />1. Measure static pressure at a point downstream from the balancing damper and adjust volume <br />dampers until the proper static pressure is achieved. <br />a. Where sufficient space in submain and branch ducts is unavailable for Pitot -tube <br />traverse measurements, measure airflow at terminal outlets and inlets and calculate <br />the total airflow for that zone. <br />2. Remeasure each submain and branch duct after all have been adjusted. Continue to adjust <br />submain and branch ducts to indicated airflows within specified tolerances. <br />Measure terminal outlets and inlets without making adjustments. <br />1. Measure terminal outlets using a direct - reading hood or outlet manufacturer's written <br />instructions and calculating factors. <br />Adjust terminal outlets and inlets for each space to indicated airflows within specified tolerances of <br />indicated values. Make adjustments using volume dampers rather than extractors and the dampers <br />at air terminals. <br />1. Adjust each outlet in same room or space to within specified tolerances of indicated quantities <br />without generating noise levels above the limitations prescribed by the Contract Documents. <br />2. Adjust patterns of adjustable outlets for proper distribution without drafts. <br />Reece, Noland & McElrath, Inc. <br />238000-4 <br />Orange County Board of Elections <br />Orange Co., NC 05/04/18 <br />