It’s no secret that it gets hot and humid in northwestern Arkansas. You can usually count on a well-maintained A/C to dehumidify your home during the day, but it might not be enough to counteract all of the moisture in the air. Air conditioners are not designed to take moisture out of the air as their main function; this is simply a side effect of the cooling process.
An air conditioner pulls air into a cooling chamber and runs it over tubes filled with cooled refrigerant to remove heat from the air. The cooling process causes moisture to condense on the pipes and then drip down into a collection pan, where it’s drained away through a plastic or metal drain line. If it doesn’t result in a significant decrease in humidity in the home, a dehumidifier may needed to make up the difference.
When excess moisture is in the air, it takes longer for perspiration to evaporate from the skin, which is how we generally reduce our body temperature. We perceive the rate of heat transfer from the body, not the temperature itself, so when this rate is slower, we feel warmer. Lowering the relative humidity in the home will increase the rate of heat transfer and make us feel cooler.
There are two main types of dehumidifier:
A chemical absorbent drying dehumidifier is usually used as a whole-house device. In it, a silica gel pulls the moisture from the air. An exchange wheel takes the desiccant to an air loop that dries it and exhausts the warmed, damp air outdoors through a duct line.
A portable heat pump variety works on the same principle as an air conditioner except refrigerant in the coils is super-cooled to bring incoming air to near freezing temperatures. This causes more condensation and pulls a lot of moisture from the air. This condensation is collected in a bucket or run to a drain with a hose. The air is returned to the room, slightly warmer than before.
For information on adding a dehumidifier to help your A/C dehumidify your home, please contact us at Paschal Heat, Air, & Geothermal.
Our goal is to help educate our customers in Northwest Arkansas about energy and home comfort issues (specific to HVAC systems). For more information about A/Cs and other HVAC topics, download our free Home Comfort Resource guide.
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