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DocuSign Envelope ID: 9826C043- 4C32- 49CD- A4CC- DC28ABAB7CE7 <br />SECTION 238000 - TEST AND BALANCE <br />1. Measure condenser -water flow to each cell of the cooling tower. <br />2. Measure entering- and leaving -water temperatures. <br />3. Measure wet- and dry -bulb temperatures of entering air. <br />4. Measure wet- and dry -bulb temperatures of leaving air. <br />5. Measure condenser -water flow rate recirculating through the cooling tower. <br />6. Measure cooling tower pump discharge pressure. <br />7. Adjust water level and feed rate of makeup -water system. <br />3.12 PROCEDURES FOR CONDENSING UNITS <br />A. Verify proper rotation of fans. <br />B. Measure entering- and leaving -air temperatures. <br />C. Record compressor data. <br />3.13 PROCEDURES FOR BOILERS, WATER HEATERS, AND OTHER FUEL FIRED EQUIPMENT <br />A. If hydronic, measure entering- and leaving -water temperatures and water flow. <br />B. If steam, measure entering -water temperature and flow and leaving steam pressure, temperature, <br />and flow. <br />C. Record the following data: <br />1. Equipment drawing designation; <br />2. Equipment manufacturer, model number, and serial number; <br />3. Rated input and output; <br />4. Type of fuel and heat value (calorific value); <br />5. Other data from the nameplate of the equipment. <br />D. Record the following measurements: <br />1. Percent carbon dioxide <br />2. Stack temperature (flue gas temperature at equipment outlet) <br />3. Ambient temperature <br />4. Over -fire draft (inches WG) <br />5. Gas burner manifold pressure <br />6. Fuel meter reading (see below) <br />7. Boiler jacket temperature <br />E. Fuel meter readings shall be determined as follows: <br />1. Natural Gas: The objective of this test is to determine gross MBH input. <br />a. Time the gas meter under each firing rate to determine the CFH (cubic feet per hour) <br />delivered. CFH shall be calculated by the equation: CFH equals U value of timing dial <br />for one rotation times 36,000 divided by time in seconds for one rotation of timing dial. <br />b. Measure or determine the gas pressure at the gas meter and apply the proper <br />correction factor to the delivered CFH that was measured to determine the equivalent <br />CFH at the rated gas pressure. This shall be determined by the following equations: <br />F = (UPa + PgO) /(Pa + Pr) <br />Where F = Correction Factor; Pa = Atmospheric pressure (psi); Pg = Gas pressure at meter (psi); Pr = <br />Rated gas pressure And Rated CFH = Measured CFH x Correction Factor <br />2. Oil Fired: The oil pressure at the pump shall be measured and recorded. Oil flow rate shall <br />be determined from manufacturer's data and nozzles installed. <br />3. LP Gas Fired: The burner manifold pressure shall be measured and pressure read at tank, <br />before and after each regulator under system full load conditioning for all gas fired equipment <br />simultaneously. Gas flow rate shall be determined using manufacturers data as applicable. <br />F. If burners have other than one firing rate, combustion tests shall be made in the following manner: <br />1. If step- firing (High -Low), readings shall be taken at each step. <br />2. If modulating, reading shall be taken at high, at low, and at 50 percent firing rate. <br />G. The following calculations shall be made from the measured data and recorded on the report: <br />1. Gross Input <br />2. Net Stack Temperature <br />3. Percent Excess Air <br />4. Percent Flue Gas Loss <br />5. Combustion Efficiency <br />6. Gross Output (MBH) = Gross Input - Flue Gas Loss <br />H. Flue gas loss shall be calculated from measured data using industry accepted methods. <br />3.14 PROCEDURES FOR HEAT - TRANSFER COILS <br />A. Water Coils: Measure the following data for each coil: <br />1. Entering- and leaving -water temperature. <br />2. Water flow rate. <br />3. Water pressure drop. <br />4. Dry-bulb temperature of entering and leaving air. <br />5. Wet -bulb temperature of entering and leaving air for cooling coils. <br />6. Airflow. <br />7. Air pressure drop. <br />Reece, Noland & McElrath, Inc. 238000-6 Orange County Board of Elections <br />Orange Co., NC 05/04/18 <br />