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• Backup kits are also an important consideration
if a freezer is located in areas where power
failures are common. CO2 backup kits alert
sta of a power problem, while maintaining
set temperature for a short time to allow
sta to correct the problem. If a ULT freezer is
located in an area experiencing frequent power
outages (which lacks backup generators) or
susceptible to hurricanes and/or other natural
disasters, consider backup options.
Energy concerns
• The facility manager should be aware of
additional heat load the ULT freezer will
cause. Energy management strategies to
mitigate the additional heat load may involve
consolidating all of the freezers into one
room with adequate cooling, or dispersing
the heat load by separating ULT freezers to
dierent locations.
• “Advances in ULT freezer compressor design,
insulation, and cabinet design have resulted in
greater eciencies to store samples. However,
the eciency of ULT freezers decreases over
time, due to loosening seals, refrigerant loss,
degraded lubricants, fatigue in mechanical
systems , or poor maintenance. Each year of a
ULT freezer’s age translates to approximately
3% increase in energy consumption. Some
ULT freezers age well; therefore, it is highly
recommended to test every freezer to verify the
need for replacement.”
• Some customers have a committee managing
cold storage which watches energy use and
performance over time.
• Regularly testing old freezers over time will
show which ones are the poor performers.
A four to six hour test with a plug-in energy
meter helps compare the voltage, wattage,
and amperage drawn for each freezer.
Price is always a consideration
• To oer low cost freezers, manufacturers
eliminate certain components. Low cost
freezers are risky for users who need stable,
reliable performance and other options that
indicate product quality.
• Moderately priced freezers will provide
consistent -85°C temperatures and protect
against oil logging. They may even include
USB ports to plug in and manually download
operation data. VIP options exist in this
category, and the same freezer performance
can be had paying double.
