How Does A Dehumidifier Work?



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By installing a dehumidifier in your crawl space or basement, you can maintain a consistent humidity throughout your home and thus, prevent countless problems. Controlling the humidity in your home can help to prevent mold, pests, and structural damage, plus provide a more comfortable environment for your family to live in. While you may be aware of some of the benefits that a dehumidifier can provide, you might not know exactly how a dehumidifier works. The dehumidifier process can be explained in a few simple steps:

Change Set Point on Dehumidifier

Step #1 - All Seaira Global dehumidifiers come standard with a built-in humidistat that automatically monitors the humidity of the surrounding environment. Simply program the humidistat to your desired set point (the level you want the humidity to remain around) and the humidistat will start the dehumidifier as necessary to maintain that relative humidity level.

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Step #2 - Once the humidistat in the dehumidifier detects that the ambient conditions are outside of the set point, it will signal the dehumidifier to turn on. To start the process, the fan and compressor will run.

Signal Dehumidifier to turn on


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Fan draws air through grill and across coils

Step #3 - The fan motor will then draw in air through the grill (and filter if you have opted to use a prefilter on your dehumidifier) and across the coils to start the dehumidfying process.

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Step #4 - At this point, the air is directed to the cold evaporator coils. The difference in temperature between the air and the evaporator coils causes the moisture in the air to condense.

Coils cause air to condense
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Condensation drips into drain pan

Step #5 - The condensation, caused by the air cooling, on the dehumidifier's evaporator coils will then drip down the coils and into the drain pan on the bottom of the dehumidifier.

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Step #6 - Meanwhile, the air continues to travel to the warm condenser coils in the center of the dehumidifier, where it is heated back up (10°-15° warmer than when it entered the machine).

Air travels onto warmer coils
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Conditioned air blown out

Step #7 - Finally, the conditioned air is blown out of the exhaust duct on the side of dehumidifier.

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To sum it up, when the conditions are outside of the set point, the dehumidifier will draw in the humid air, remove the moisture, and return the conditioned air to the space. While returning the conditioned air back into the space, the water that was collected on the dehumidifier coils will drip into the drain pan and out of the dehumidifier. Thus, instead of a humid, uncomfortable environment, you will have a comfortable, well conditioned home.

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