YL Instruments YL9100 HPLC, User Manual

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YL9112 Isocratic Pump
Problem Cause How to fix
Pressure upper
limit is loaded.
-Tubing inside is blocked.
-Check valve is blocked.
-Solvent is changed.
-Replace blocked tubing by
loosening to be from tail side
in turn.
-Replace outlet check valve.
-Wait until solvent is completely
changed.
Pressure
increases or
decreases.
-Change of solvent is
incomplete.
-Wait until change is completely
performed.
-Wait until pressure is stable.
Solvent is not
flowed out
-Air bubble is in pump head.
-Air separation status of
solvent is bad.
-Check valve is not good.
-Liquid containing oil flows
into head part.
-Perform prime/purge again.
-Take measures so that air
separation condition of solvent
may be good, and perform
prime/purge again.
-Wash or replace check valve.
-Remove oil in head sufficiently
with strong organic solvent
using prime/purge port.
Pressure is
unstable.
-Check valve is bad or
defected.
-Air separation or mixing
conditions of solvent is
bad.
-Compression compensating
reference
value of configuration
mode is wrong.
-Cam shaft is loosened.
-High pressure seal was
worn.
-Pump head was loosened.
-Wash or replace check valve.
-Use mobile phase with well mixed
solvent, and improve air separation
condition.
-Initialize compensation value or
re-input proper value.
-Tighten wrench bolt of cam shaft
-Replace high pressure seal.
-Tighten nut of pump head.
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