7.1 Problems and their solutions
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872 Extension Module IC Pump
7 Troubleshooting
7.1
Problems and their solutions
Problem
Cause
Remedy
Marked rise in pres-
sure
6.2821.120 inline filter
blocked.
Drift of the baseline
Eluent – Evaporation of the
organic solvent in the elu-
ent.
Check the eluent bottle attachment
.
Very noisy baseline
High pressure pump – con-
taminated pump valves.
Eluent – Leak in the eluent
path.
Check the eluent path.
Eluent – Blockage in the
eluent path.
Check the eluent path.
High pressure pump –
defective piston seals.
Replace piston seals
Pulsation damper not con-
nected.
Connect pulsation damper
Background conduc-
tivity too high
Incorrect eluent.
(see Chapter 6.3.2.3, page 40)
Poor reproducibility
of the retention
times
Eluent – Leak in the eluent
path.
Check the eluent path.
Eluent – Blockage in the
eluent path.
Check the eluent path.
Unexpected change
to the retention
times in the chroma-
tograms
Eluent – Gas bubbles in the
eluent.
Check connections of the eluent degasser
.
High pressure pump –
defective.
Request Metrohm Service.
Vacuum is not being
built
Eluent Degasser – Connec-
tor
Vacuum
on the rear of
the instrument not (tightly)
sealed.
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Seal the connector
Vacuum
tightly with a
6.144.6040 threaded stopper.
or when using an 872 Extension Module: