Eppendorf New Brunswick -86 °C Freezers Premium - Manual (Page 22)

Premium -86 °C Freezers — Operating manual
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6.1.5 Vacuum effect
After closing the freezer door following access to the contents, a vacuum may be created. Before
the door can be opened again, it may be necessary to wait two or three minutes for the vacuum
to be released by the vent port. Do not try to force the door. During the release of the vacuum,
a slight hissing may be heard. In order to minimize vacuum formation, the vent heater assembly
has a spring-loaded plunger to clear ice from the inside of the vent.
6.2 Programming the freezer
Set the freezer to any temperature within the range from -50 °C to -86 °C.
6.2.1 Setting operating temperature
To set the operating temperature for the freezer:
1. Press the LOCK key.
The LOCK lamp will illuminate, indicating the system is unlocked and parameters can be
changed.
2. Press the SET TEMP key.
Its indicator will flash and the display will indicate 0.
3. Using the numerical keys, enter a new temperature (from -50 °C to -86 °C).
The temperature selected will appear in the TEMPERATURE display.
4. When the correct temperature is displayed, press the E key to enter the data. To set the high
alarm setpoint skip to (see Setting high alarm setpoint on p. 22), step 2.
The SET TEMP lamp will go off.
5. Press the LOCK key to exit programming.
The LOCK lamp will go off and the freezer will return to normal mode.
6.2.2 Setting high alarm setpoint
The high alarm setpoint may not be warmer than -10 °C and may not be less than within +5° of
the operating temperature. The default setting is +5° from the temperature setpoint.
1. Press the LOCK key.
The LOCK lamp will illuminate, indicating the system is unlocked and parameters can be
changed.
2. Press the HIGH ALARM key.
Its indicator will flash and the display will indicate 0.
Hint!
Be careful not to place a rack directly against the vent, as this will inhibit the plunger’s ability to
operate correctly (see Heated vent port on p. 28).
Hint!
All temperature setpoints are automatically negative °C.
Hint!
The LOCK lamp will flash if a lock code (password protection) is required, (see Changing lock
codes on p. 24).
Hint!
Press the C key to clear the display during programming.
Hint!
The LOCK lamp will flash if a lock code (password protection) is required, (see Changing lock
codes on p. 24).
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Op
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