76 • Chapter 6: Maintenance
GasWatch 3 for CO and O
2
7. Install the new charcoal filter. It should be seated and recessed in the center of the sensor
gasket.
8. Reinstall the white hydrophobic filter. It should be seated and recessed in the sensor gasket
and should not overlap the edge of the sensor gasket.
9. Reinstall the sensor retainer and tighten its screw.
Replacing the Hydrophobic Filter
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. The hydrophobic filter and the sensor gasket should stay on the sensor.
5. Remove the old hydrophobic filter.
6. Install the new hydrophobic filter. It should be seated and recessed in the sensor gasket
and should not overlap the edge of the sensor gasket.
Hydrophobic Filter (White)
Sensor Retainer
Screw
Sensor Gasket
Charcoal Filter (Black)
Figure 11: Replacing the Charcoal Filter
Sensor Retainer
Screw
Sensor Gasket with
Charcoal Filter
Hydrophobic Filter (White)
Figure 12: Replacing the Hydrophobic Filter