BUCHI KjelSampler K-377 - Manual (Page 134)

7 Maintenance
134 K-375/376/377 Operation Manual, Version B
7 .5 .2 Decalcification of the steam generator
To decalcify the steam generator proceed as follows:
1. Make sure that the steam generator is cooled down (switch off the unit and let it cool
down for at least 30 minutes)
2. Remove the water of the steam generator (see 9.1 Emptying the steam generator)
3. Mix about 0.8 L of solution for decalcification (use approx. 160 g citric acid or 80 g ami-
dosulfuric acid dissolved in 0.8 L water)
4. Remove the hose from the H
2
O pump on the back of the device and connect another
hose with the pump
5. Dip this hose into the decalcification solution
6. Switch on the K-375
7. After initialization the pump starts running
8. Switch off the unit after the steam generator is filled with the solution (pump stops run-
ning)
9. Let the solution dissolve the lime for 0.5 – 1 hour
10. Remove the solution of the steam generator (see step 1 and 2)
11. Perform a second decalcification (see step 5 – 10)
12. Connect the hose from the water tank with the pump for H
2
O
13. Flush the steam generator 2 – 3 times with distilled water (see step 6 – 8 and 10)
14. Perform 2 – 3 times a CLEANING (cleaning procedure) of the instrument
7 .5 .3 Replacement of the sodium hydroxide pump
The pump for sodium hydroxide is considered as an expendable part which needs to be replaced
once per year as a proactive measure.
Proceed as follows:
! WARNING
Serious chemical burns by corrosives.
• Observe all data sheets of the used chemicals.
• Handle corrosives in well ventilated environments only.
• Always wear protective goggles.
• Always wear protective gloves.
• Always wear protective clothes.
• Do not use damaged glassware.
! Warning
Death or serious injuries by contact with high voltage.
• Make sure device is switched off and unplugged before replacing the pump.