Humidifier

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A humidifier is a household appliance that increases humidity (moisture) in a room. There are point of use humidifiers, which are commonly used to humidify a single room, and whole house or furnace humidifiers, which connect to a homes HVAC system to provide humidity to the entire house.

Contents

1 Anatomy of a humidifier

1.1 Reservoir
1.2 Wick
1.3 Fan

2 Other types of humidifiers
3 Risks
4 See also

Anatomy of a humidifier

The most common humidifier, an "evaporative" or "wick humidifier", consists of just a few basic parts: a reservoir, wick and fan.

Reservoir

Reservoirs are common to all humidifiers and come in different shapes and sizes. The reservoir is a containing tank of water filled prior to operation, and provides the water for the moisture output.

Wick

The wick is a filter that absorbs water from the reservoir. Evaporation of water from the wick is dependent on relative humidity. A room with low humidity will have a higher evaporation rate compared to a room with high humidity. Therefore, this type of humidifier is self-regulating: As the humidity of the room increases, the water vapor output naturally decreases. These wicks regularly need cleaning and replacement--if this does not happen, the humidifier stops humidifying the area it is in and the water in the tank remains at the same level.

Fan

The fan is adjacent to the wick and blows on the water the filter evaporates.

Other types of humidifiers

Other types of humidifiers include:

Vaporizer (Steam Humidifier) - Boils water, releasing steam and moisture into the air. The least expensive of humidifiers, you can add medicated inhalant to the water to help reduce coughs. It produces the noisy sound of boiling water.
Impeller Humidifier - A rotating disc flings water at a diffuser, which breaks the water into fine droplets that float into the air.
Ultrasonic Humidifier (Cool Mist Humidifier) - A metal diaphram vibrating at an ultrasonic frequency creates water droplets that exit the humidifier in the form of a cool fog. Although silent, Ultrasonic Humidifiers should be cleaned regularly to avoid bacterial contamination which may be projected into the air.

If impeller and ultrasonic humidifiers are not used with distilled water, minerals in the droplets precipitate as a fine dust. Depending on the volume, this dust may have negative health effects. Wick humidifiers trap the mineral deposits in the wick.

For buildings with a forced-air furnace the humidifer may be built right into the furnance. A pipe brings water directly to a reservoir attached to the furnance. The wick is typically a drum attached to a motor that rotates the wick through the reservoir. The furnance blower is the humdifier fan.

Risks

The use of a humidifier can allow the reproduction of dust mites or the growth of harmful mold, which can be especially harmful for children and the elderly. The relative humidity should not normally be increased above 55%.[link]