CareFusion PrinterNOx Operating Manual page 18

Should the water trap fill during the course of the measurement, it
will overflow into the integral hydrophobic PTFE filter, cause an
obstruction, and the following message will be displayed:
Unscrew the two retaining screws, and remove the water trap from
the PrinterNOx.
Empty the accumulated water into a suitable container by
connecting a syringe (20ml minimum size) with the adapter supplied
and pushing air through the assembly as shown below.
Gas Line Occluded
or water trap full
Please clear blockage
or empty water trap
and filter.
16
Syringe
adapter