Metrohm 930 Compact IC Flex Oven/ChS Manual page 94

6.1
Problem
The retention times
in the chromato-
gram have changed
unexpectedly.
Peak areas are lower
than expected.
Data of the separa-
tion column cannot
be read.
￭￭￭￭￭￭￭￭
86
Cause
Guard column – Blocked.
Separation column –
Blocked.
Injection valve – blocked.
Eluent - Incorrect concen-
tration
Separation column –
Diminished separating effi-
ciency.
The eluent contains gas
bubbles.
High-pressure pump –
Defective.
Sample – There is a leak in
the sample path.
Sample – The sample path
is blocked.
Sample – The sample loop
is not (completely) filled.
Sample – There are gas
bubbles in the sample.
Column chip dirty.
Column chip is defective.
￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
Remedy
Note: 6.2821.180 pump tubing connection
with filter must be used.
Replace the guard column (see Chapter 3.17,
page 42).
Regenerate the separation column (see
￭
Chapter 5.14.4, page 83).
Replace the separation column (see "Con-
￭
necting the separation column", page 46).
Note: Samples should always be microfiltered .
Have the valve cleaned (by a Metrohm service
engineer).
Create eluent with correct concentration.
Regenerate the separation column (see
￭
Chapter 5.14.4, page 83).
Replace the separation column (see "Con-
￭
necting the separation column", page 46).
Deaerate the high-pressure pump (see Fig-
￭
ure , page 41).
Request Metrohm Service.
Find and fix the leak in the sample path.
Find and eliminate the blockage in the sample
path.
Adjust the transfer time for the sample (see
"Determining the transfer time", page 81).
Use the sample degasser .
Clean the contact surfaces of the column chip
with ethanol.
1. Save column configuration in MagIC Net.
2. Notify Metrohm Service.
930 Compact IC Flex Oven/ChS (2.930.2200)