Metrohm 820 IC Separation Center - Manual (Page 85)

4.3 Faults and malfunctions
819 IC Detector / 820 IC Separation Center
77
4.3 Faults and malfunctions
4.3.1 Malfunctions and their rectification
If difficulties appear with the IC system during analyses, their causes
are best investigated in the order separating column → pump →
eluent → 819/820 IC System. Several of the malfunctions which may
appear are listed in the following table with details of possible causes
and countermeasures.
Malfunction Cause Rectification
Baseline with high
noise level, pulsa-
tion • Contaminated pump
values
• Faulty piston seals
• Quality of the pump
does not suffice for the
selected sensitivity
• Clean the valves (see Sec-
tion 4.1.3)
• Replace the piston seals
(see Section 4.1.3)
• Use pulsation dampener,
use more powerful pump or
lower the sensitivity
Drift of the base-
line • Thermal equilibrium not
yet reached
• Leak in system
• Evaporation of organic
solvent in eluent
• Condition system with
heating switched on
• Check connections and
make leakproof
• Ensure better closure of
eluent supply vessel
Considerable
pressure drop • Leak in system • Check connections and
make leakproof
Considerable
pressure rise • Contamination of the
filter in the 6.2821.120
Filter unit PEEK
• Change of column pack-
ing by injection of con-
taminated samples
• Replace the 6.2821.130
Filter (see Section 2.7.3)
• Regenerate the column
(see Section 4.1.2) or re-
place column
Note:
Samples should always
be microfiltered.
Chromatograms
with poor resolu-
tion, change in the
retention times • Deterioration in separa-
tion efficiency of the IC
column • Regenerate the column
(see Section 4.1.2) or re-
place column
Extreme peak
broadening, split-
ting (double
peaks) • Dead volume at the col-
umn ends • Fill column with glass
beads (
∅ ≤ 100 µ m) or
replace column