Metrohm 889 IC Sample Center - Manual (Page 52)

6.2 Analytical problems
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889 IC Sample Center
Problem Cause Remedy
The blank is contaminated. ￭ Use a new blank.
￭ Do not fill the sample vessel completely in
order to avoid contamination of the air
needle.
The cause is not clear. Examine the problem more closely by varying
the washing solution.
There is no injection. The flow path is blocked. 1. Loosen the needle from the valve.
2. Carry out a standard washing procedure.
3. If washing solution is flowing out of the
injection port, check the needle. If no
washing solution is flowing out of the
injection port, remove the buffer tubing
from the valve.
4. Carry out a standard washing procedure.
5. If washing solution is flowing out of the
open end, check the rotor seal. If not, then
check the entire flow path to determine
whether the connections have been tight-
ened too firmly.
If the problem persists, undo the buffer
tubing from the syringe valve.
6. Carry out a standard washing procedure.
7. If washing solution is flowing out of the
syringe valve, check the buffer tubing. If
not, check the syringe valve.
The injection valve is leak-
ing. 1. Remove the needle connection and the
buffer tubing.
2. Connect the injection port 1 to a high pres-
sure pump.
3. Seal port 6.
4. Start the pump with a low flow rate.
5. Check port 3 and 4 for leakage.
6. If the ports 3 and 4 are leaking, check the
rotor sealing. If not, manually test the valve
again.
Warning
Observe the maximum pressure of 350 bar in order to avoid any valve
leakage.