Dehumidifiers

What is a dehumidifier?

A dehumidifier is an appliance that removes extra humidity from indoor air. It is helpful for allergy sufferers.

Humidity and allergy

Humidity is the water vapor that is suspended in the air. So obviously humidity itself does not cause allergy, but excess humidity facilitates the growth of molds, mildew and the house dust mite, which depend on humidity for their supply of water. So humidity inside the house contributes indirectly to worsening allergy and that is why allergy sufferers are frequently advised to install a dehumidifier.

How do dehumidifiers remove humidity from the air?

There are 2 types of dehumidifiers:

1. The simple dehumidifier:
   Is actually a refrigerator or air conditioner with a fancy name! Anyone with an AC unit at home must have noticed the water that drips from the unit, that is the water that is removed from the air as it is made colder because hot air can carry water vapor but as the air becomes colder the water is condensed and is collected and removed by a discharge tube.The dehumidifier removes moisture from the air in the same way (by refrigerating the air), it has 2 extra parts though, a component that reheats the air and reintroduces it into the house, and a component that re-vaporizes the collected water into the outside air.
2. The desiccant dehumidifier:
   As the name implies, it removes moisture by exposing the air to a desiccant, which is a chemical material that absorbs water and moisture.
   A desiccant dehumidifier consists of an input component that sucks the air from the house and passes it onto the second component, the housing with the desiccant chemical, and then the third component removes the resulting dry air and recycles it into the house.

Which is more effective of the 2 types?

The refrigerating or simple dehumidifier is more effective.