Hitachi CHROMASTER 5160 Instruction Manual page 764

3.4
(3) Caution on Storage
When you intend to use the degassing unit the next day
though the pump was stopped after completion of analysis,
instrument power supply may not be turned off.
However, before a long-time stop of the degassing unit, turn
off the power supply, wash adequately with ion-exchanged
water, run methanol or the like, replace the flow paths with
the air, etc., and then plug the tubes securely. This is
always required after use of a buffer, because there is a
possibility of salt precipitation, growth of
algae/microorganisms, etc. in the membrane.
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