Buchi K-424, Operation Manual

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Digestion Unit K-424 5 Operation
5.4 Carrying out the Kjeldahl digestion
• Switch the unit on and preheat for approx. 5 minutes
on stage 10.
• Wear protective goggles!
• Place the digestion tubes in the digestion tube holder
on the rack .
• Introduce the sample and reagents into the digestion
tubes
.
• Seal off unused connecting branches with the glass
cap (item No. 17396) .
Never install empty digestion tubes!
• Place the suction module with the fitted gaskets on
the digestion tube holder.
• Turn on scrubber or water jet pump bevor any gases
can develop.
5.5 Malfunctions
Malfunction Possible cause Remedy
Heating elements do not 1. Mains plug not plugged in - Connect unit to the mains
heat up 2. Unit switched OFF - Switch ON
3. Energy regulator in position „0“ - Set to position "10"
4. Energy regulator faulty - Replace regulator
5. Heating elements faulty - Replace heating element
Lamp does not light up (H 1) Lamp faulty Replace lamp
Table 4: Malfunctions
Fig. 10: Operation of the K-424