Bestherm BL-205DLR Manuel D'instructions page 18

Before refilling water, turn your unit to the "Off" position by pressing
the switch located on the back panel and unplug the power cord.
USING THE ICE BOXES
In order to increase the cooling effect of your fan, you can use the
ice boxes which are supplied with the unit. Before using, fill the ice
boxes with water and place them into the freezing compartment of
your refrigerator for a few hours. Then place them into the top
container and add water to the 'MAX' level. Using the ice boxes will
drop the temperature of the air flow which will create a more
effective cooling effect.
TECHNICAL DATA
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