Is it new? If so then make sure the room is warm, dehumidifiers will not be able to colelct water if the air is cold and the water has already condensed onto your windows or other cold surfaces. A nice warm room means more moisture is in the air and then it will be attracted to the DH.
If it isn't news give the filters a good clean.
Pumpkinhead
March 2010
Automatic Answer
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