Dräger Narkomed 2B Operator's Instruction Manual page 145

Replacing the
Oxygen Sensor
7. Raise the bottom dome, remove and empty the dust cup if loose
absorbent is present, and replace the dust cup.
8. Pull the canister release lever up to close the absorber system.
9. Perform the absorber portion of the daily checkout procedure
provided in the "Daily Checkout" section to verify proper reassembly.
Replace the oxygen sensor capsule when its sensor is depleted, because a
depleted sensor cannot correctly analyze oxygen concentrations.
1. Turn the SYSTEM POWER switch to STANDBY.
2. Remove the oxygen sensor housing from the inspiratory valve dome.
(It is a press fit.)
3. Unscrew the cover from the sensor housing and remove the sensor
capsule.
4. Install the replacement sensor in the housing. Verify that the copper
rings on the capsule mate with the electrical contacts in the sensor
housing.
5. Wait 15 minutes to let the sensor capsule stabilize to ambient air.
If you do not wait, calibration (the next step) will not be successful.
6. Restore power to the machine and calibrate the oxygen sensor, as
described in Section 5, "Operation, Oxygen Monitoring."
Routine Maintenance and Cleaning
Section 6
6-3