Humidity

Relative humidity measures humidity in the air. The term refers to the amount of moisture the air can hold at a certain temperature. One hundred percent is the maximum amount of moisture the air can hold, so when relative humidity is 50 percent that means the air is holding half the moisture possible. Warm air can hold more moisture than cool, so relative humidity changes as the temperature changes.

Air Conditioners and Humidity

An air conditioner will remove humidity, if it is the appropriate size for the space. If you have a window unit that is too large for the room, it will cool the room quickly and shut off before it has had much chance to get rid of humidity. A properly sized unit will remove enough humidity from the air to make it feel comfortable.

Humidity and Mold

Too much humidity in a home can breed mold. Mold spores float around and there is no practical way to get rid of them except by controlling humidity and moisture in the home so mold cannot grow. Allergies and stained walls are common problems in homes with continuous high humidity. Running an air conditioner when needed can help control a mold problem.

Considerations

You can keep track of the humidity level in your home by purchasing a hygrometer. A finding of excessive humidity on most days in your home would make an air conditioner a wise purchase if you live in a warm climate. Depending on the relative humidity after cooling with an air conditioner, you may also need to consider a dehumidifier to reduce humidity to a level that feels comfortable and does not cause problems.