BUCHI Rotavapo R II - Manual (Page 40)

8 Troubleshooting
40 R II Operation Manual, Version E
Table 8-1: General malfunction and their remedy
Malfunction Possible cause Corrective measure
Seal is defective Replace seal
Table 8-2: Malfunctions with vacuum controller and vacuum pump and their remedy
Malfunction Possible cause Corrective measure
Frequent switching of valve or pump System is leaky Check all sealing points (tubes and
their connections)
Chosen hysteresis is too small Choose larger hysteresis (if end-
vacuum is higher than 700 mbar,
switch to automatic hysteresis)
Vacuum is not reached Back evaporation at Rotavapor Empty receiving flask
Water pressure of water jet pump is
too low Open water tap completely
Distillation “died out” Manually decrease the pressure until
the distillation starts again
Distillation stopped, although not
dried out completely Back evaporation from the receiving
flask is too strong (especially for
solvent mixtures) Empty receiving flask and restart
distillation
Malfunction in distillation procedure
which is not exactly defined (e.g.
sudden cooling, heat flow too low,
etc.) Decrease the pressure manually until
the distillation starts again
NOTE
At the R II no errors are displayed and read out via the RS485 interface.
Reset of the overtemperature sensor at the bottom of the Heating bath B-491
Let the bath cool down and empty it. Then
push the temperature sensor reset button at
the bottom side of the heating bath e.g. by
means of a tooth stick.
Fig. 8.1: Heating bath B-491 bottom view