dehumidifiers use and capacity

Dehumidifiers are simple and affordable devices that can solve some situations of excess moisture and humidity. You can regulate dehumidifiers to get the ideal RH (Relative Humidity) level: something between 35% and 45%.

Obviously there are also structural causes of moisture and condensation, demanding other means and strategies:

See:

Controlling high levels of humidity
Moisture and insulation
Natural Ventilation
Mechanical ventilation
Basics on Humidity

Dehumidifiers and energy efficiency

Dehumidifiers energy-efficiency is measured in liters of water removed per kilowatt-hour of energy consumed: Litters/kWh. A higher ratio means usually a better energy performance. Ratios between 1 and 3L/KWh are common.

Buying dehumidifiers: their capacity and performance

Dehumidifier capacity is measured in pints per day. The higher the number of pints the higher the capacity of the humidifier. Dehumidifiers with 40-65 pints are very common today.

When shopping, have in mind the energy efficiency and the capacity of the humidifier, but also the area that needs dehumidification and its situation. The chart below allows an estimation of the humidifier minimum capacity (number of pints) for several basic conditions and areas.

Condition without Dehumidification	Area (Sq. Feet)
Condition without Dehumidification	500	1,000	1,500	2,000	2,500
Moderately Damp (space feels damp and has musty odor only in humid weather)	10	14	18	22	26
Very Damp (space always feels damp and has musty odor. Damp spots show on walls and floor.)	12	17	22	27	32
Wet (space feels and smells wet. Walls or floor sweat, or seepage is present.)	14	20	26	32	38
Extremely Wet (laundry drying, wet floor, high load conditions.)	16	23	30	37	44

hart source: Energy Star and AHAM (Association of Home Appliance Manufacturers)

Energy Star Dehumidifiers and qualified brands

Consider qualified dehumidifiers models with the UE eco-labels (European countries) and Energy Star ratings. Qualified models are slightly more expensive but they will ensure better performance and lower energy consumption.

Manufacturers

Manufacturers and brand names as Amana, Amcor, Comfort Aire, Danby, Dayton, De'Longhi, Fedders, Friedrich, Frigidaire, GE, GoldStar, Haier, Home Hardware, Kenmore, LG, Maytag, Therma-Stor, Therma-Stor, Whirlpool, Woods have excellent qualified models.

Dehumidifiers and Water Removal

Typical dehumidifiers use a removable plastic bucket and an automatic shutoff when the bucket is full of water. You won’t have to worry about the bucket overflowing.

To avoid the need of emptying the bucket, typical dehumidifiers allow hooking a hose to the bucket and direct it into a floor drain (or sump pump).

Cares

Make sure the dehumidifier is connected to a properly grounded outlet. Keep drain hoses and water drainage away from electrical circuits, connections and devices. For better operation, locate the dehumidifier properly; air should circulate freely around it.

Locate the dehumidifier away form dust and dirt sources. Doors and windows should be closed while the dehumidifier is running.

Operating Temperature

Frost can form on the condensing coils of the humidifier whenever air temperature drops below 65ºF, affecting their efficiency. Buy a model able to overcome that limitation. Some models are able to work at very low temperatures.

Humidity, Humidistats and Hygrometers

Many dehumidifiers include a built-in device (a humidistat) to automatically set the desired humidity level. If your dehumidifier does not have a built-in humidistat, you may purchase a hygrometer. Hygrometers measure humidity levels and enable people to monitor when to turn the dehumidifier on and off.