Dehumidifiers

A dehumidifier is a small and simple air conditioner that draws the air over the cold coil or evaporator to condense the moisture and then the dry air passes through the hot coil or condenser to heat it back up to its original temperature.

Anyone who has seen a cold glass of water on a hot, humid day has seen the process of dehumidification in action. When air cools it loses its ability to hold moisture. The same thing happens in a dehumidifier or air conditioner. The moisture in the air inside the room condenses onto the air conditioner's or dehumidifiers cold coils and effectively dries the air.

If you have a central air conditioner it is possible that it can be modified to work like a separate dehumidifier in addition to the moisture that is removed during its usual cycle. You will need a thermidistat or humidistat and other controls added by a professional contractor.

Some dehumidifiers use chemical adsorbents to remove moisture from the air without cooling it. This type of dehumidifier is designed primarily for hot, humid climates and tends to use more energy that a traditional dehumidifier. Chemical adsorbent dehumidifiers absorb moisture from the air with a drying agent like silica gel which is on a wheel and exhausts the damp air outdoors through a special duct.

Some people make homemade dehumidifiers by using bags of road salt to absorb moisture from their air. The wet salt drips into a pan or drain drying the air. Because salt is highly corrosive to metals and hard on the skin this method can be troublesome and ineffective for large areas.