BUCHI Rotavapo R-250 - Manual (Page 31)

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Rotavapor R-250 6 Maintenance
6.6 Testing for Leaks
With the assembled rotary evaporator in a clean and dry
condition, test it to ensure that the vacuum system is free of
leaks. To do this, evacuate the unit to below 100 mbar and
then close the vacuum line. The rate of pressure rise must
not exceed 3 to 5 mbar per 15 minutes.
A greater pressure rise indicates a leakage. In such a case,
recheck all EasyClamp connections and all valves.
6.7 Changing the Battery and Calibrating the
Pressure Gauge (Accessory)
Changing the battery
The service life is 360 hours. If the display indicates that the
battery is low, change it. Battery type CR2430. Switch the
unit off and on again after the battery has been changed.
When the button is pressed in, the following commands
are displayed during operation. If the button is released, the
corresponding command is executed.
s
release at Exe)
To obtain an absolute reading on the display, connect the
unit to the lowest possible vacuum and set the zero point
SEE
6.8 Customer Service
No intervention on or in the unit is permissible except when
done by authorized Service personnel. These are individu-
als with a well-backed technical professional training and
knowl edge of the dangers that result from a failure to observe
the safety precautions required. BÜCHI’s Customer Service
rep resentatives have available to them a Service Manual
specific to the unit in question. That manual is issued only
to authorized Service personnel.
The addresses of BÜCHI’s official Customer Service rep-
resentatives are shown on the back cover of this Operation
Manual. Please turn to these representatives should you
have any malfunctions, technical questions, or problems in
using the unit.
BÜCHI’s Customer Service Dept. will be ready and happy to
offer the following services:
s