GasWatch 3 for CO and O
2
Chapter 6: Maintenance • 77
7. Reinstall the sensor retainer and tighten its screw.
Replacing the Sensor
1. Verify that the GasWatch 3 is off.
2. Use a small Phillips screwdriver to unscrew the sensor retainer’s screw.
3. Remove the sensor retainer.
4. Remove the sensor gasket and filters. The filters may fall out. The sensor is exposed.
5. Remove the old sensor from its socket.
6. Carefully insert the replacement sensor. Be sure that the new sensor’s orientation slots are
aligned correctly. Do not force the sensor into its slot.
7. Reinstall the sensor gasket. Be sure to orient it as shown in Figure 13 above.
8. Reinstall the charcoal filter. It should be seated and recessed in the center of the sensor
gasket.
9. Reinstall the hydrophobic filter. It should be seated and recessed in the sensor gasket and
should not overlap the edge of the sensor gasket.
10. Reinstall the sensor retainer and tighten its screw.
11. Calibrate the new sensor as described on pg.43.
Figure 13: Replacing the Sensor
Sensor
Charcoal Filter (Black)
Sensor Gasket
Hydrophobic Filter (White)
Sensor Retainer
Screw
