Energy efficiency is important in dehumidifiers. Differences of only 85 watts may add 20 kWh daily to your summer electric bill. Some models let the fan run continuously to circulate air back to the humidistat. Since in most situations the moisture content will be the same throughout the enclosed area being treated, this may be an unnecessary energy expense.
Place the dehumidifier at least 6 inches from the nearest wall where air can flow freely to and from all sides. Avoid locating it in a room corner or near a large piece of furniture. Shut all doors and windows to the area to be dehumidified.
For the first few days of operation, turn the humidistat, if the model has one, to drier or "extra dry." This aids moisture removal from furnishings as well as room air. After the area has dried, adjust the humidistat to your particular comfort level.
Before you empty the water pan or bucket, turn the machine off and also disconnect the power cord. This eliminates any possibility of electric shock if you spill water and there is a fault in the grounding
system of the unit or your home wiring. Be sure the area, the unit, and you are dry before you reconnect the cord.
Dehumidifiers operate most effectively at air temperatures about 70 F. At temperatures below 65 F frost may form on the coils (which are kept cold to condense as much moisture as possible). If this happens, shut it off, and wait for it to defrost before running again. Frost cuts down air circulation so the dehumidifying process does not work, and may damage the coils. This problem usually occurs in cool basements in spring or fall; check the appliance if temperature hovers near that point.
As water condenses out of the air, heat is given off, raising the temperature slightly in the area around the appliance. This warmer air results in a lower relative humidity.