Desiccant dehumidifiers allow you to achieve humidity levels as low as 5 or 10% which may be needed for special applications. Dessicant dehumidifiers do not remove the moisture from the air by using a refrigeration system. Air is drawn in from the room and passes through what is called a desiccant wheel containing a highly absorbent material like silica where it is able to draw the moisture from the air. This dried air is then circulated back into the room out the other side. Since there is no refrigeration system used, the moisture can be removed regardless of the air temperature or humidity. The only other thing that is necessary for this kind of dehumidifier to be efficient is that the desiccant wheel needs to be regenerated, so it can continue to absorb more moisture from the air. The way this is done is to circulate air from the opposite direction that has been heated in some fashion through the wheel, so the heat and moisture removed can be exhausted to the outside. Because of how a desiccant dehumidifier works it is both expensive and more difficult to install. We recommend Novel-Aire desiccant dehumidifiers.
If you want more options, see our complete selection of dehumidifiers.