Alerts: A number of events may occur during a lyophilization procedure that will cause an
alert to be displayed on the Freeze Dryer touch screen. An audible alarm (beeper)
will also be sounded that will automatically be muted after one minute.
The specific alert type can be identified by observing the message box on the
display. The alert message box and audible alarm can be dismissed by pressing the
“Back” button on the alert message box. The following conditions will initiate an
If a power failure occurs during a Freeze Dry process, the vacuum control valve
will allow air to bleed into the Freeze Dryer System. If the failure is of a short
duration and the collector does not warm up above -30°C, when power is restored
the Freeze Dryer will restart and resume operation of the refrigeration and vacuum
systems. If the power failure lasts for a longer duration and the collector warms
above safe limits, when the power is restored, the Freeze Dryer will not
automatically restart. This prevents melted sample from being drawn into the
collector and prevents liquid from being drawn into the vacuum pump.
When power is restored, the POWER FAIL alert message will be displayed on the
touch screen and the audible alarm will sound.
If the voltage supplied to the Freeze Dryer varies beyond allowable limits, the
LINE VOLTAGE RANGE alert will be activated. The high and low alarm points
are preset at the factory to correspond to the normal allowable voltage variations
based on the nominal voltage specified for the freeze dryer. Some models may be operated outside the normal voltage limits (see Appendix C). If necessary, the high
and low LINE VOLTAGE OFFSETS may be adjusted from the Settings /
After the collector temperature has cooled to below -40°C, an alert will be
activated if the collector temperature rises above –40°C for more than 5 minutes.
If there is liquid in the collector chamber and either the COLLECTOR or
VACUUM start button is pressed, neither function will start and an alert will be
activated. This feature prevents the inadvertent start of the vacuum pump when
liquid is in the collector and thereby can extend the life of the vacuum pump.
A few drops of liquid may remain in the drain hose after draining. When the
vacuum pump is started these drops may be sucked into the collector chamber.
The vacuum pump normally plugs into the vacuum pump electrical receptacle on
the back of the Freeze Dryer. When the Freeze Dryer has accumulated a total of
1000 operating hours, an alert will be activated. It may be necessary to service the
vacuum pump more frequently than every 1000 hours depending on the operation
of the Freeze Dryer. The pump oil should be regularly monitored to verify that
it is clean. The “Set hours between oil change” can be reprogrammed from the
Settings / Maintenance screen for any value from 0 to 9999 hours.
If the vacuum level in the freeze dryer has not reached at least 5 mbar within 30
minutes of starting the vacuum, an alert will be activated and the vacuum pump
will be turned off (if it is plugged into the Freeze Dryer vacuum pump outlet).
If the system is unable to achieve the vacuum set point (during Manual or Program
mode), an alert will be activated. This alert will be activated if the vacuum level is
not within 0.500 mbar of the vacuum set point in 20 minutes.