Metrohm 940 Professional IC Vario ONE/SeS/PP/HPG - Manual (Page 113)

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6 Troubleshooting
940 Professional IC Vario ONE/SeS/PP/HPG (2.940.1540)
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Problem Cause Remedy
Note: 6.2821.180 pump tubing connection
with filter must be used.
Guard column – Blocked. Replace the guard column (see Chapter 3.22,
page 56).
Separation column –
Blocked. ￭ Regenerate the separation column (see
Chapter 5.17.4, page 100).
￭ Replace the separation column (see "Con-
necting the separation column", page 60).
Note: Samples should always be microfiltered .
Injection valve – Valve
blocked. Have the valve cleaned (by a Metrohm service
technician).
The retention times
in the chromato-
gram have changed
unexpectedly. Separation column –
Diminished separating effi-
ciency. ￭ Regenerate the separation column (see
Chapter 5.17.4, page 100).
￭ Replace the separation column (see "Con-
necting the separation column", page 60).
The eluent contains gas
bubbles. ￭ Ensure that the connectors for the eluent
degasser are firmly connected .
￭ Deaerate the high-pressure pump (see Fig-
ure , page 55).
High-pressure pump –
Defective. Request Metrohm Service.
Peak areas are
lower than
expected. Sample – There is a leak in
the sample path. Find and fix the leak in the sample path.
Sample – The sample path
is blocked. Find and fix the blockage in the sample path.
Sample – The sample loop
is not (completely) filled. Adjust the transfer time for the sample (see
"Determining the transfer time", page 98).
Sample – There are gas
bubbles in the sample. Use the sample degasser .
MCS – The CO
2
suppressor
is not connected.
Connect the CO
2
suppressor.
The peristaltic pump
is pumping too little. Peristaltic pump – Contact
pressure too weak. Correctly set the contact pressure .
Peristaltic pump – Filter
blocked. Replace the filter (see "Replacing the filter",
page 96).