CIRAS-3 Operation Manual V. 1.09
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When changing out desiccants, the user must take care to ensure that the columns are properly seated in
the correct manifolds, the proper desiccant is used in appropriate columns which are clearly marked and
that all “O” rings are in place and slightly lubricated with silicone grease. Any leakage of ambient air into
the gas circuit generally results in error messages during ZERO or fluctuating CO2r values during
measurement.
Molecular Sieve Repackaging
The Molecular Sieve is originally supplied by PP Systems in tin packaging.
After initial opening, we strongly urge all users to repackage the Molecular
Sieve in small glass containers with a screw top to seal the desiccant from
room air. This desiccant saturates very quickly in room air and if not properly
stored it will cause it to go bad and subsequently affect CO
2
readings and
calibration.
To ensure a good seal, we also recommend putting some electrical tape
around the screw top as shown here. If you have any questions, get in
contact with PP Systems.
TIP
Always change the molecular sieve at least once per week during use regardless of operation time.
Each absorber column includes the following items which should be checked periodically and replaced
when necessary.
Foam Filters
The gray foam filters used inside the absorber columns become worn over time and should be inspected
regularly and replaced when torn or reduced in size. The foam must be of an open celled type, such as
packing foam. The foam filters at the bottom of each column will likely require more frequent changes
versus the upper foam filters.