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Orange County West Campus Office Building -HVAC <br />PDC Project 23020 General Commissioning Requirements 01 91 13 - 6 <br />A.Calibrate all field-installed temperature,relative humidity,carbon monoxide,carbon dioxide,and <br />pressure sensors and gauges,and all actuators (dampers and valves)on this piece of equipment <br />shall be calibrated. Sensors installed in the unit at the factory with calibration certification provided <br />need not be field calibrated. <br />B.Calibrate using the methods described below;alternate methods may be used,if approved by <br />Commissioning Authority and Owner beforehand. See PART 2 for test instrument requirements. <br /> Record methods used on the relevant Prefunctional Checklist or other suitable forms, <br />documenting initial,intermediate and final results. <br />C.All Sensors: <br />1.Verify that sensor location is appropriate and away from potential causes of erratic operation. <br />2.Verify that sensors with shielded cable are grounded only at one end. <br />3.For sensor pairs that are used to determine a temperature or pressure difference,for <br />temperature make sure they are reading within 0.2 degree F of each other,and for pressure, <br /> within tolerance equal to 2 percent of the reading,of each other. <br />4.Tolerances for critical applications may be tighter. <br />D.Sensors Without Transmitters -Standard Application: <br />1.Make a reading with a calibrated test instrument within 6 inches of the site sensor. <br />2.Verify that the sensor reading,via the permanent thermostat,gauge or building automation <br />system,is within the tolerances in the table below of the instrument-measured value. <br />3.If not,install offset,calibrate or replace sensor. <br />E.Sensors With Transmitters -Standard Application. <br />1.Disconnect sensor. <br />2.Connect a signal generator in place of sensor. <br />3.Connect ammeter in series between transmitter and building automation system control <br />panel. <br />4.Using manufacturer’s resistance-temperature data,simulate minimum desired temperature. <br />5.Adjust transmitter potentiometer zero until 4 mA is read by the ammeter. <br />6.Repeat for the maximum temperature matching 20 mA to the potentiometer span or <br />maximum and verify at the building automation system. <br />7.Record all values and recalibrate controller as necessary to comply with specified control <br />ramps,reset schedules,proportional relationship,reset relationship and P/I reaction. <br />8.Reconnect sensor. <br />9.Make a reading with a calibrated test instrument within 6 inches of the site sensor. <br />10.Verify that the sensor reading,via the permanent thermostat,gauge or building automation <br />system,is within the tolerances in the table below of the instrument-measured value. <br />11.If not,replace sensor and repeat. <br />12.For pressure sensors,perform a similar process with a suitable signal generator. <br />F.Sensor Tolerances for Standard Applications: Plus/minus the following maximums: <br />1.Watthour,Voltage,Amperage: 1 percent of design. <br />2.Pressure,Air,Water,Gas: 3 percent of design. <br />3.Air Temperatures (Outside Air,Space Air,Duct Air): 0.4 degrees F. <br />4.Relative Humidity: 4 percent of design. <br />5.Barometric Pressure: 0.1 inch of Hg. <br />6.Flow Rate,Air: 10 percent of design. <br />7.Flow Rate,Water: 4 percent of design. <br />8.AHU Wet Bulb and Dew Point: 2.0 degrees F. <br />G.Critical Applications: For some applications more rigorous calibration techniques may be required <br />for selected sensors. Describe any such methods used on an attached sheet. <br />3.07 TEST PROCEDURES -GENERAL <br />A.Provide skilled technicians to execute starting of equipment and to execute the Functional Tests. <br /> Ensure that they are available and present during the agreed upon schedules and for sufficient <br />duration to complete the necessary tests,adjustments and problem-solving. <br />Docusign Envelope ID: 8DED1454-68D2-4E36-9FC6-E56FF2124E5D