8 Troubleshooting
K-375 / K-376 / K-377
Operation Manual, Version E
145
8 Troubleshooting
This chapter helps to resume operation after a minor problem has occurred with the instrument. It
lists possible occurrences, their probable cause and suggests how to remedy the problem.
The troubleshooting table below lists possible malfunctions and errors of the instrument. The operator
is enabled to correct some of those problems or errors by him/herself. For this, appropriate corrective
measures are listed in the column “Corrective measure”.
The elimination of more complicated malfunctions or errors is usually performed by a BUCHI technical
engineer who has access to the official service manuals. In this case, please refer to your local BUCHI
customer service agent.
8.1
Problems that may occur
It is not possible to start a determination
∙ The steam generator is in stand-by mode. Activate the steam generator by pushing the “Ready”
button.
No sample transfer from K-376 / K-377 to K-375
∙ Check the system for leakages (K-376 / K-377, K-375 and transfer tubes/connections)
∙ Check the position of the dip tube on the K-376 / K-377: distance between sample tube bottom
and dip tube must be about 2 mm. If necessary, adjust the dip tube accordingly
∙ Check the system by means of a Priming. If this does not help, check the glass tubes in the
K-376 for cracks and tube height.
Crystallized samples
∙ Dissolve the crystallized sample by warming it up. Otherwise sample transfer is not possible.
Typical mistakes digestion
Crystallization after digestion
∙ False ratio of H
2
SO
4
to catalyst
∙ Digestion time too long
∙ Suction capacity of scrubber too strong
∙ Leakage in the suction system
Samples do not get clear
∙ No or too little catalyst used
∙ Digestion temperature too low
∙ Temperature too high – sealing material was flushed into the sample
Fume leakage
∙ Seals are defective
∙ Suction capacity of scrubber too weak
∙ Leakage in the system, e.g. hose connector not tight
∙ Blocked hoses
∙ Reduced suction on the bypass valve
