Metrohm 940 Professional IC Vario ONE/ChS/LPG - Manual (Page 102)

6.1
￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
94 ￭￭￭￭￭￭￭￭
940 Professional IC Vario ONE/ChS/LPG (2.940.1250)
Problem Cause Remedy
Suppressor – Backpressure
too high. Clean the suppressor (see Chapter 5.12.3.3,
page 83) or replace parts (see Chapter
5.12.3.4, page 85).
The background
conductivity is too
high. The suppressor is not con-
nected. Connect the suppressor (see Chapter 3.13,
page 30).
The incorrect eluent is
being used. Change the eluent (see Chapter 5.5.2, page
62).
Suppressor – No or insuffi-
cient flow of regeneration
solution or rinsing solution. Check the flow of the regeneration solution
and the rinsing solution .
The retention times
are poorly reprodu-
cible. The eluent path has a leak. Check all of the connections along the eluent
path and fix the leak.
The eluent path is blocked. Check the eluent path and fix the blockage.
The eluent contains gas
bubbles. ￭ Inspect the connectors for the eluent
degasser .
￭ Deaerate the high-pressure pump (see
Chapter 3.20, page 46).
Baseline increasing
strongly. Suppressor – Reduced
capacity. Regenerate the suppressor (see Chapter
5.12.3.2, page 82).
SPM – Reduced capacity. Regenerate the SPM (see Chapter 5.12.3.2,
page 82).
Chromatograms
have poor resolution Separation column –
Diminished separating effi-
ciency. ￭ Regenerate the separation column (see
Chapter 5.15.4, page 90).
￭ Replace the separation column (see "Con-
necting the separation column", page 53).
Extreme spread of
the peaks in the
chromatogram.
Splitting (dual
peaks) Capillary connections –
dead volume in the system. Check the capillary connections (see Chapter
3.2, page 14) (use PEEK capillaries with an
inner diameter of 0.25 mm between the injec-
tion valve and detector).
Guard column – Dimin-
ished efficiency. ￭ Replace the guard column (see Chapter
3.21, page 49).
Separation column – Dead
volume at the column
head. ￭ Install the separation column in the oppo-
site flow direction (if permitted by the leaf-
let) and rinse into a beaker.