Dehumidifiers are chosen based on several factors. One major factor is the dehumidifier size. Now, before choosing a dehumidifier you need to be aware of the severity of your humidity condition. A large dehumidifier will dehumidify a large area in a short time. A small dehumidifier will take longer to dehumidify a large area. Also, large dehumidifiers will effectively deal with severe humidity conditions compared to small dehumidifiers. Small dehumidifiers will however fit perfectly in small spaces like bathrooms and crawl spaces.