5. Hold down the ‘Boost Air Curtain’ button and press the ‘Decrease Temperature’ button to force the unit intolow fan speed (Whisper Quiet Mode).6. Wait 10 minutes to ensure stability of the Whisper Quiet Mode.7. Select wrench icon on display screen to bring up setup menu. Select Cal Oxygen on the setup menu toinitiate calibration.8. When calibration is completed, 100% oxygen is delivered for approximately 20 seconds to ensure thereare no occlusions in the system. Do not turn off the unit or disconnect the oxygen supply during this briefperiod after the ‘Calibration Complete’ screen appears. Exit calibration screen.9. Select O2 icon on display screen to bring up Servo Control Oxygen menu. Set O2 set point to 65%.10. Start timer and verify that unit reaches 60% in less than 10 minutes.nOTE: If rise time is longer than 10 minutes check all tubing between the O2 sensors and the chassis ventfitting. The chassis vent may be identified by its mushroom cap shaped cover.nOTE: Unit should not be placed in service unless the calibration is successful and the rise time test passes.nOTE: The Low O2 alarm may activate during the rise time test. Silence the alarm and let the test continue.nOTE: The “O2 Cal Lost – No O2” alarm may appear after the unit is turned on or returned from power failcondition. If this alarm appears, calibrate the oxygen sensors (using the wrench icon and the Cal Oxygenoption) and resume use. If this alarm appears during normal operation, calibrate and continue use, but callservice.2.4.3 Supply Valve Leak Test1. Connect oxygen supply to Servo Oxygen fitting.2. Disconnect the 10mm hose from the expansion chamber.3. Power up unit in Service Mode.4. Scroll to Servo Oxygen service screen, and open V1 & V2 and verify that gas flows audibly .5. Close V1 & V2 and place the 10mm hose in a cup of water. Verify that no more than 10 bubbles appear overa one minute period. If unit fails, replace supply valves.When test is completed, reattach 10 mm hose to expansion chamber.© 2001 by Datex-Ohmeda, Inc.. All rights reserved. 6600-0356-000 103 13Chapter 2: Service Checkout