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Orange County Health Department Improvements Smith Sinnett /2024008 <br />Hillsborough,NC Orange County Asset Management Services <br />TESTING,ADJUSTING,AND BALANCING FOR HVAC 23 05 93 - 4 <br />11.Duct system leakage is minimized. <br />B Submit field reports. Report defects and deficiencies that will or could prevent proper system balance. <br />C Beginning of work means acceptance of existing conditions. <br />3.03 PREPARATION <br />A Hold a pre-balancing meeting at least one week prior to starting TAB work. <br />1.Require attendance by all installers whose work will be tested,adjusted,or balanced. <br />B Obtain design drawings and specifications and become thoroughly acquainted with the design intent. <br />C Obtain copies of approved shop drawings of all air handling equipment,outlets (supply,return,and exhaust) <br />and temperature control diagrams. <br />D Compare design to installed equipment and field installations. <br />E Walk the system to determine variations of installation from design. <br />F Check filters for cleanliness. <br />G Lubricate all motors and bearings. <br />3.04 ADJUSTMENT TOLERANCES <br />A Air Systems Tolerances <br />Systems -Air Tolerances of Drawing <br />Design Remarks <br />Air Handling Units,Fans <br />(Supply,Return,Exhaust)-5%to +10%Systems with Filters must be tested at <br />dirty conditions <br />Outdoor Air 100%to 110%To obtain this accuracy requires <br />ductwork be traversed <br />Terminal Units +/-5% <br />Calibrate all boxes at minimum of two <br />points.Single point calibration is not <br />acceptable. <br />Diffusers and Grilles +/-10%If design is less than 100 CFM, <br />tolerance can be +/-10 CFM <br />Pressurized Rooms -Positive <br />Supply +100-105% <br />Exhaust or Return 100- <br />95% <br />Room offset tolerance to design 100% <br />to +110% <br />Pressurized rooms -Negative <br />Supply 95%to 100% <br />Exhaust or Return 100% <br />to 105% <br />Room offset tolerance to design 100% <br />to 105% <br />3.05 RECORDING AND ADJUSTING <br />A Field Logs: Maintain written logs including: <br />1.Running log of events and issues. <br />2.Discrepancies,deficient or uncompleted work by others. <br />3.Contract interpretation requests. <br />4.Lists of completed tests. <br />B Ensure recorded data represents actual measured or observed conditions. <br />C Use only those instruments which have the maximum field measuring accuracy and are best suited to the <br />function being measured. <br />D Apply instrument as recommended by the manufacturer. <br />E When averaging values,take a sufficient quantity of readings that will result in a repeatability error of less <br />than 5 percent.When measuring a single point,repeat readings until 2 consecutive identical values are <br />obtained. <br />F Permanently mark settings of valves,dampers,and other adjustment devices allowing settings to be restored. <br /> Set and lock memory stops. <br />Docusign Envelope ID: 2D852F9B-A7CF-462A-9536-444A53AA848A