How To Use A Dehumidifier

The main purpose of a dehumidifier is to extract moisture in the air, helping you maintain optimal humidity. High levels of indoor humidity can cause discomfort and difficulty in breathing. If left unattended, it can also lead to mold and mildew growth, pest infestation, rust, and corrosion. 

The best solution to these problems is a dehumidifier. Depending on the type of space, its size, moisture content, and temperature, there is a particular dehumidifier you can use to maximize dehumidification. 

Whether you’re looking to buy a new unit or you have one that doesn’t seem to be working effectively, here you can learn all about the ways using a dehumidifier can help you.

Frigidaire FFAD5033W1 Dehumidifier

How Your Dehumidifier Works

There are two types of dehumidifiers based on the methods they use to remove moisture: refrigerant and desiccant. Similar to how an air conditioner works, refrigerant dehumidifiers work through a process of condensation to collect moisture. 

The fan draws humid air and passes it over the refrigerant coils. As the air cools, the moisture condenses and is collected in a tank or drained through a hose. The dryer air is then reheated and exhausted into the room. A refrigerant dehumidifier is usually excellent in warm climates. Most consumer grade models start to decline in performance at 65F or lower. 

On the other hand, a desiccant dehumidifier uses a substance that absorbs or adsorbs moisture from the air. They come in different sizes but the full-size models are about the same in appearance as their refrigerant counterpart. 

The humid air that is drawn into the dehumidifier runs through the process zone of the desiccant rotor. Moisture clings to the surface of the desiccant material and separates from the air molecules. A heater warms the circulated air before it passes through the remaining part of the rotor. Moisture is then transferred from the desiccant to the warm air. The desiccant is now renewed so it can adsorb more moisture. 

These processes of adsorption and desorption occur continuously and simultaneously as the desiccant wheel rotates. Since they don’t use condenser coils, dehumidifiers are more versatile in terms of operating temperatures.

Another method of dehumidification that mini dehumidifiers often use is called the Peltier effect or thermoelectric cooling. It is based on the idea that a voltage of electricity creates a temperature difference between the two sides of a Peltier module.

Humid air is drawn by a small fan on one end of the unit and enters through the cold side on the front. As the air cools, the moisture condenses and drips down to the water tank. The cold, dry air then passes through the hot side. The now warmer and dryer air exits through this side.


1. Pick the perfect size dehumidifier.

The size of a dehumidifier refers to its capacity to remove moisture. Getting the right size dehumidifier for your space maximizes its effectiveness and efficiency. If you use a dehumidifier with a smaller capacity than you need, it has to work really hard to keep up, yet it still won’t be able to drain out all the moisture. Overworking your appliance can lead to its early death.

To find the right dehumidifier size, measure the area of the space you need to dehumidify. Also take note of the amount of moisture that needs to be removed. For commercial spaces, some other factors that may affect your decision are the air temperature and humidity levels you need to maintain. 

If you notice visible signs of excessive moisture like condensation on surfaces, mold growth, or rust on metal, you may want to go with a higher capacity unit. It’s always a good idea to get the next bigger size than you actually need so that the unit won’t have to work at the highest settings.

2. Find the best location to place your dehumidifier.

Where and how you install your dehumidifier can dictate how well it performs. To find the best location for your dehumidifier, look for the main source of humidity in the area. Keep all the doors and windows closed while operating so that the unit works only on the specified area. Ideally, you want a central location for maximum coverage, but you can also place the unit in one corner or side of the room for your convenience.

No matter where you place your dehumidifier, make sure that the air isn’t blocked from the intake and exhaust grilles. Keep the unit at least 6-8 inches from walls or furniture to maintain airflow. The ideal position of your dehumidifier is also impacted by its capacity, dimensions, and drainage options. You need to be able to access it to empty the water tank. Or, if the condensate continuously flows from a hose or pump, there must be a nearby drain or sink. You also need to think about the power supply since the unit has to be plugged directly into a wall socket.

3. Set your dehumidifier in the correct humidity level.

The next step is to put in your preferred humidity level. Modern dehumidifiers usually have onboard controls that allow you to do this. The ideal range for a residential area is around 30-50%. For storage areas and other commercial spaces with more specific needs, you may adjust the humidity level accordingly. Make sure the dehumidifier you have can perform as needed.

Most of the higher capacity dehumidifiers feature a humidistat which automatically adjusts the relative humidity level. It’s important that you pick the exact setting you need. It’s wise to only keep your dehumidifier on continuous operation when it’s absolutely needed. This way you can save energy and give the device a little downtime.

Even with a humidistat in place, it’s good practice to monitor humidity levels to ensure that your unit is working effectively. If necessary, you may set up a separate hygrometer to keep track of the humidity in the area.

4. Use your dehumidifier in the right temperatures.

Dehumidifiers generally perform better in higher temperatures. Refrigerant models are mostly used in hot and humid climates, although some high capacity commercial units are tough enough to operate in temperatures as low as 33°F. If the air gets too cold, the condensate may freeze on the condenser coils and damage the machine.

Some of the best residential dehumidifiers feature auto defrost which automatically shuts off the unit to allow the ice to melt. Even with this feature, it’s important to inspect the coils regularly to prevent any problem. If you really need to operate in cold conditions, use a dehumidifier specifically designed for this purpose.

Desiccant dehumidifiers are your best option for dehumidifying in cold conditions that refrigerant models cannot handle. Commercial units can go even down to subzero temperatures. If you need to control the humidity level in your business, make sure you use a dehumidifier that can operate at the exact temperature you need.

Ecor Pro EPD50 Desiccant Dehumidifier

5. Empty the water collected.

Dehumidifiers extract moisture from the air and turn it into condensate. This is then collected in an internal tank that you can take out for manual drainage. Usually, when the tank is full, an indicator lights up and the dehumidifier shuts off. 

If you want to keep the unit running when you’re away, you can attach a hose to the outlet to divert the water. That is one possible drawback if you don’t have a sink or drain nearby. Also remember that this continuous draining option works via gravity. This means the dehumidifier has to be on a higher level than the drain so that the water can drip down through the hose.

High capacity dehumidifiers also offer an internal pump which automatically pushes out the water. This may be a necessary feature for rooms without a floor drain or sink available. With an automatic pump you can have the drain hose positioned vertically up to a certain height. For a dehumidifier without this feature, you have an option to get an external pump.

6. Keep the dehumidifier clean.

Frequent cleaning helps maintain proper functioning and prolong the life of any appliance. Dehumidifiers typically require very little maintenance, but you must still check up on your unit from time to time. Dirt, mold, and bacteria accumulate on the machine and eventually get in the air. To ensure your health and comfort and help your dehumidifier last long, clean the unit at least every few weeks. 

Take out the air filter and wash it with liquid soap. Each model has a recommended period in which you need to change out the filters. Use a damp cloth to wipe the exterior and vacuum the inside to remove any remaining dirt or debris. Let everything dry completely before reinstalling. 

These are only some basic rules you can follow to keep your dehumidifier working effectively and efficiently. Consult the owner’s manual for more specific guidelines.

Benefits of Using a Dehumidifier

Dehumidifiers come in a variety of sizes and with different features for all types of applications. Using a dehumidifier for residential or commercial areas will benefit the entire property and everyone involved. 

A dehumidifier removes moisture and contributes to better air quality. It also eliminates mold spores, dust mites, and other common allergens in the air. This reduces the risk of allergies, asthma attacks, and other respiratory issues. 

Dry air lowers the chances of mold and mildew growth. This preserves the structural integrity of your house or other property. Drywalls and floors are especially susceptible to moisture and high humidity. Maintaining the humidity level within optimal range helps prevent rapid destruction caused by condensation, rust, corrosion, or pest infestation.

Adding a whole-house dehumidifier to your HVAC system gives you more control over the humidity level and temperature. High humidity can cause discomfort or a muggy and sticky feeling. Instead of turning up your air conditioner, you can use a dehumidifier to maintain a comfortable relative humidity, thereby saving more energy.


Other ways to control indoor relative humidity

If you still notice signs of dampness after using a dehumidifier, or you have yet to install one, here are some ways that can help reduce indoor humidity.

Improve ventilation. Open all windows and doors or install vents if possible. Get some fans running to let the air flow. Whenever you cook or take a hot bath or shower, turn on your exhaust fans or simply open a window. This helps keep the excess moisture and odors out.

If you need to keep the doors closed, use your air conditioner. Although it’s not as efficient as a dehumidifier, your AC naturally helps reduce relative humidity as it cools the air indoors. 

Try some alternative options for a dehumidifier. Just put calcium chloride in a bucket or a large bowl and place it where you have excess moisture. You may also use moisture absorbers you can easily get from your kitchen pantry such as rock salt and baking soda.

Avoid hanging wet clothes indoors. Moisture from the clothes evaporates into the air and makes it feel heavy and sticky. The best solution is to hang your laundry outside, but if this isn’t possible, you can also use a dryer or fan.

Check your plumbing. Fix any leaking pipes under sinks, in the bathroom, or in the basement. If you notice damp spots on your walls or floor, this can be a sign of a leak.

Each of these methods can help lower humidity levels. Some will take extra effort, time, and money. If you have serious humidity problems, these may not be enough to fully address them. The wisest course of action may be to simply invest in the best dehumidifier according to your needs.

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