Metrohm 874 USB Oven Sample Processor - Manual (Page 47)

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874 Oven Sample Processor ￭￭￭￭￭￭￭￭ 39
6 Troubleshooting
6.1 Problems and their solutions
Problem Cause Remedy
The drift is very high
during conditioning. Molecular sieve of drying
flasks and/or the titration
cell exhausted. Replace molecular sieve.
The titration cell is leaking. Check seals. If necessary, replace.
The titration time is
too long. The sample is non-homo-
genous Reduce the size of the sample or homogenize
it before weighing in.
Not the entirety of the
moisture is expelled. Select more stringent switch-off criteria on the
KF titrator: lower stop drift, higher switch-off
delay time.
Tubing connections leaking Inspect tubing and replace as necessary.
The results are
spread widely. Molecular sieve of drying
flasks exhausted. Replace molecular sieve.
Condensate in the heating
tube. ￭ Dry the tubing.
￭ Reduce the gas flow.
￭ Perhaps lower the oven temperature.
Gas flow too high. Reduce the gas flow.
The sample is non-homo-
genous Reduce the size of the sample or homogenize
it before weighing in.
Selected gas flow is
not achieved. System is leaking Check all tubing connections and drying flasks
for leaks.
Pressure from external gas
supply either too low or
too high. Adjust gas pressure (max. 0.3 bar).
Pump defective Contact a service technician.