Waters 1525M - Page 81

Troubleshooting 81
5
Pump not delivering
eluent (continued)
Immiscible eluents in pump
head
Purge the pump with appro-
priate eluents. Verify miscibility
of eluents being used and
change to more miscible
eluents.
Dirty or malfunctioning inlet or
outlet check valve
Replace the check valves (see
Section 4.4
or Section 4.6).
Damaged plunger seal (indi-
cated by eluent leaking from
behind the pump head or by
salt crystal build-up around the
back of the pump head)
Verify if both pump heads can
maintain pressure as outlined
in Section 4.2.2
. If a head is
leaking, replace the plunger
seal (see Section 4.3
or
Section 4.5
).
Pump cavitation due to one of
the following:
• Eluent reservoirs positioned
at or below pump height
• Loose, bent, or blocked inlet
tubing
• Improperly degassed eluent
• Dirty eluent reservoir inlet
filter
• Volatile eluents in pump
head
• Tubing ID too small
Perform the following correc-
tive action:
• Raise eluent reservoirs
above the pump.
• Check tubing. Tighten,
straighten, or replace
tubing.
• Degas.
• Replace the filter.
• Prime the pump (see
Section 3.2.1
).
• Use correct tubing.
Ruptured high-pressure pulse
dampener
Contact Waters Technical
Service.
Defective pump motor Contact Waters Technical
Service.
Defective circuit board Contact Waters Technical
Service.
Table 5-1 Correcting Pump Problems (Continued)
Symptom Possible Cause Corrective Action