Dehumidifiers FAQ's

Dehumidifiers FAQ's


A dehumidifier is a household or an industrial appliance that reduces the level of humidity in the air, usually for health reasons of man, machine & equipments. Humid air can cause mold and mildew to grow inside homes, which has various health risks. Very high humidity levels are also unpleasant for human beings, can cause condensation and can make it hard to dry laundry or sleep. Uncontrolled moisture during production, processing, storage and packaging is undeniably a major menace for the industry.

Higher humidity is also preferred by most insects, including clothes moths, fleas and cockroaches. Relative humidity in dwellings is around 50%. Dehumidifiers are also used in industrial climatic chambers for keeping desired humidity levels.


Dehumidification is the process of removing excess moisture from the air in your room or covered area and is primarily accomplished through the use of a dehumidifier. Dehumidifiers work by combining three basic principles: cooling the air, adsorption, and absorption.

By using coolant, dehumidifiers cool the air below the dew point which causes the moisture in the air to condense. The water is captured in a drain bucket. This same principle is also true for commercial/industrial dehumidifiers. Our dehumidifiers come equipped with larger fan motors, drain buckets, or internal condensate pumps to condense, collect and drain water away.

Condensation in electric items may cause irreparable damage, and can even be dangerous. Musty smells can develop, and eventually mold, mildew and fungus will appear. These can be damaging to your health. The recommended indoor humidity level is around 50%. Dehumidifiers can help to keep your home within those levels, but there are many different types available, and lots of features to choose from. Exploring the pages of this site will help you to decide what the best dehumidifier is for your situation.


Most of our everyday activities contribute to increased humidity in the home. Showering can add a 1/2 pint of water into the air. Simply preparing meals adds approximately 5 pints of water to indoor air for a family of four over course of a day. Washing your laundry, mopping, using the dishwasher and even indoor plants contribute moisture to indoor air.

Our most basic activity of breathing can add 1/2 a pint of moisture to the air over four hours. In a home of 1000 square feet with constant temperature, four to six pints of water can increase relative humidity from 15% to as much as 60%. As you can see, the most basic activities have a growing impact on indoor humidity levels. In a relatively short period of time, elevated humidity levels create a suitable environment for mold and dust mites to flourish.


Relative humidity is a percentage showing how much water vapor is currently trapped in the air relative to the maximum amount of water vapor the air can hold at a given temperature. Your relative humidity level is the ratio of the current amount of water vapor in the air relative to the maximum amount of water vapor it will hold at a given temperature.


There really is no easy answer to this question, and deciding which model and size is right for you will depend on several factors. You need to ask yourself several questions before purchasing.

  • • How severe is my moisture problem?
  • • How large is the room/location where the dehumidifier will be used?
  • • Under what conditions will my dehumidifier typically operate?
  • • Is energy consumption a primary concern?
  • • Will I port the unit or empty the drain bucket?
  • • Number of Persons?
  • • What are the activities inside?


Place a dehumidifier so it has free air flow in a room, a few feet from a wall. Dehumidifiers work by taking humidity out of the air, but also by heating the air as it runs through its condenser when discharged from the unit.


Dehumidifiers work by forcing condensation on cold surfaces. Humid air is drawn over cooled fins that makes moisture condense on the large cool surface. The condensation is allowed to drain from the fins into a collection tank, or is piped to a suitable drain. The fins are kept cool in the same way a fridge or an air conditioner keeps cool. In many respects a dehumidifier is similar to an air conditioner, with similar components (fan, condenser, cooling fins, refrigerant and pump) Mechanical dehumidifiers should not be confused with hydroscopic granules or crystals which are attract moisture from the air to the material.


Advance desiccant dehumidification systems remove moisture from the air by using a desiccant; a material which easily attracts and holds water vapor.

Desiccant dehumidifiers are especially well-suited for removing moisture from air at a low temperature and low humidity level.

At the heart of these dehumidifiers is a patented desiccant wheel made up of corrugated material. Air passes through the flutes of the material, contacting the desiccant. The incoming process air stream gives off its moisture to the desiccant. The process air is dry as it leaves the wheel. The humidity-laden wheel rotates slowly into a second, smaller airstream which has been heated.

This smaller exhaust airstream, known as reactivation air, warms the desiccant. The warmed desiccant gives off its moisture which is then carried away by the reactivation air. The newly dried desiccant material is rotated back into the process air, where it absorbs moisture once again. Desiccant dehumidification systems have become increasingly popular in recent years because of lower equipment costs achieved through economies of scale, modular designs, and the use of desiccant silica gel wheels. It should be noted that whereas the reactivation heat in the original desiccant systems was produced by burning natural gas, all electric desiccant systems are now available. These desiccant systems are extremely efficient and simple in that they use rejected heat from the condenser to regenerate the desiccant wheel.


The performance of any one dehumidifier is mainly dependent on the ambient humidity and temperature. Condensation on the cooling surface is enhanced when there is a greater temperature inversion on the surface (i.e. greater difference between the temperature of the air and that of the surface) The greater the ambient temperature, the more water they extract, and the higher the relative humidity then the more water that the unit will extract.

The performance is also affected by dust. All dehumidifiers will have some form of dust filter to protect the coils, however these only protect them for a period of time and they do need to be maintained. Disposable filters require changing and washable types require occasional cleaning. Some dust will penetrate the filter stage and accumulate on the condensation fins, which will have the effect of slightly reducing the performance. Performance can also be affected by the filter blocking therefore preventing enough humid air flow into the unit.