Dehumidifier


Also found in: Dictionary, Thesaurus, Medical, Wikipedia.

dehumidifier

[‚dē·yü′mid·ə‚fī·ər]
(mechanical engineering)
Equipment designed to reduce the amount of water vapor in the ambient atmosphere.

Dehumidifier

A mechanical device that removes water vapor in the air inside a building, by lowering it below the dew point.

Dehumidifier

Equipment designed to reduce the amount of water vapor in the atmosphere. There are three methods by which water vapor may be removed: (1) the use of sorbent materials, (2) cooling to the required dew point, and (3) compression with aftercooling.

Sorbents are materials which are hygroscopic to water vapor. Solid sorbents include silica gels, activated alumina, and aluminum bauxite. Liquid sorbents include halogen salts such as lithium chloride, lithium bromide, and calcium chloride, and organic liquids such as ethylene, diethylene, and triethylene glycols and glycol derivatives.

Solid sorbents may be used in static or dynamic dehumidifiers. Bags of solid sorbent materials within packages of machine tools, electronic equipment, and other valuable materials subject to moisture damage constitute static dehumidifiers. A dynamic dehumidifier for solid sorbent consists of a main circulating fan, one or more beds of sorbent material, reactivation air fan, heater, mechanism to change from dehumidifying to reactivation, and aftercooler.

The liquid-sorbent dehumidifier consists of a main circulating fan, sorbent-air contactor, sorbent pump, and reactivator including contactor, fan, heater, and cooler. This unit will control the effluent dew point at a constant level because dehumidification and reactivation are continuous operations with a small part of the sorbent constantly bled off from the main circulating system and reactivated to the concentration required for the desired effluent dew point.

A system employing the use of cooling for dehumidifying consists of a circulating fan and cooling coil. The cooling coil may use cold water obtained from wells or a refrigeration plant, or may be a direct-expansion refrigeration coil. In place of a coil, a spray washer may be used in which the air passes through two or more banks of sprays of cold water or brine, depending upon the dew-point temperature required.

Dehumidifying by compression and aftercooling is used when the reduction of water vapor in a compressed-air system is required. This is particularly important, for example, if the air is used for automatic control instruments or cleaning of delicate machined parts. The power required for compression systems is so high compared to power requirements for dehumidifying by either the sorbent or refrigeration method that the compression system is not an economical one if dehumidifying is the only end result required.

dehumidifier

Any device or apparatus for removing moisture from air.
References in periodicals archive ?
A dehumidifier won't do much good if you don't empty it.
Typical cyclic internal air temperature and humidity simulations were presented for energy and dehumidifier wheels that are similar to those of Zhang and Scott (1993) for heat transfer.
TIP: Avoid another cause of condenser coil icing by running the dehumidifier only in spaces where the temperature is at least 65 degrees F.
Gilman has published a newspaper notice today announcing the termination of supply of the dehumidifier concerned.
TechNavio's report, the Portable Air Humidifier and Dehumidifier Market in the US 2014-2018, has been prepared based on an in-depth market analysis with inputs from industry experts.
2 million dehumidifiers under 12 other brand names in September 2013.
One thing I would like to add to that is that armorers need to make sure the dehumidifier is actually working.
Manufactured by Hoffman, one of Schroff's sister companies within the Pentair Group, the H20MIT system consists of a compact thermoelectric dehumidifier and a corrosion-resistant vent drain.
These include the possibility of cooling the air by manipulating the air and liquid flow rates, the lower regeneration temperatures required by liquid desiccants, and the fact that liquid systems generally do not require complex dehumidifier geometries and thus can be easily applied to various commercial and industrial applications.
com), has launched what it says is the smallest and most powerful dehumidifier in the world.
Michael Giordano, Fedders' president, director and chief executive officer-elect, said that room air and dehumidifier margins, which represented about 55 percent of the company's sales in the quarter, took the hardest margin hits, with gross profit margins in the retail channel at about 5 percent.
The trio were all staff from Lancashire-based firm Links Units (Engineering) which installed the dehumidifier at the Copthorne hotel.