What is humidity?
Humidity is most often referred to as a muggy or saturated feeling in the air; it’s essentially a measure of how much water is in the air at any given moment. There are two types of humidity, absolute humidity and relative humidity. The former is the actual amount of humidity in the air, while the latter is the ratio of the current absolute humidity to the maximum possible absolute humidity. A relative humidity of 90% would mean that the air is almost entirely saturated, and that only 10% more moisture would bring the air to full saturation.
Who needs a dehumidifier?
A dehumidifier is an important appliance for anyone who experiences any level of humidity. Humid air in your home can lead to health problems and damage to your home. High humidity contributes to lung conditions and aggravate allergies because it contributes to mold and dust mite growth. Humidity in your home can also lead to peeling wallpaper, damaged furniture, degradation of wood in your floor or walls, swelling doors, termite infestations, stains, and condensation in windows. Even low levels of humidity can irritate allergies and lead to long-term damage, so even if you only use a dehumidifier during the summer it can still be a good investment.
How do I know if I need a humidifier?
The American Society of Heating, Refrigerating, and Air Conditioning Engineers has created Standard Environmental Conditions for Human Occupancy, and recommends that the relative humidity in your home be no more than 50% in the summer and no more than 40% in the winter. You can purchase a cheap hygrometer to measure the humidity levels in your home, but many times you can tell you need a humidifier just by the comfort level of your home. If you have creaky wood floors or notice a lot of water build-up in your windows, or a musty odor in your home, it is a good time to consider investing in a dehumidifier.
How do dehumidifiers work?
There are two types of dehumidifiers. Desiccant dehumidifiers use a drying substance to get rid of excessive moisture in the air; air is streamed through the machine and the desiccant matter within the machine removes the moisture. Mechanical dehumidifiers work like air conditioners, with hot and cold coils in the unit. A fan draws air into the machine, and the air passes over the cold coil, which collects the moisture. The air then moves to the hot coil, which brings the air back to its room temperature. A mechanical model might release slightly warmer air.
Do I need a desiccant model or a mechanical model?
A desiccant dehumidifier will generally be less expensive than a mechanical model; if you live in an area with low humidity, a desiccant model will do just fine. Moderate to high humidity requires a mechanical dehumidifier to efficiently remove excess air moisture.
What size dehumidifier do I need?
A dehumidifier is measured in pints. In general, you should choose a dehumidifier based on the size of the room you will use it in and how humid it is in your home. The larger the room and more humid the air, the bigger dehumidifier you will need. A good guideline from the Association of Home Appliance Manufacturers dictates that a 500 square foot room will need a 10 pint dehumidifier for low humidity and 16 pints for high humidity, while a 2,500 square foot room will need a 26 pint dehumidifier for low humidity and 44 pints for high humidity. A smaller humidifier, running constantly, still will not have the capacity to remove a noticeable amount of moisture from the air in a large room, so it’s definitely worth your while to buy the appropriate sized humidifier for your home.
What if I want to dehumidify my whole house?
For dehumidifying your entire home, over 1500 square feet, consider having a professional dehumidifier installed by an HVAC technician. A whole house dehumidifier will be installed right into your HVAC system through you’re homes ductwork. You can also purchase a very large, standalone dehumidifier for one floor of your home. Just make sure you place it in a central location where all areas of the house can be affected.
What features should I look for in a dehumidifier?
Some good features to look for in a dehumidifier include portability, a built-in humidistat, and continuous drainage. Portability is important if you plan on using your dehumidifier in multiple rooms throughout your home; many models are very lightweight and have wheels or a carrying handle to make this easy for you. A built-in humidistat will help you control the humidity levels in your home but automatically measuring humidity levels and turning the unit on or off automatically depending on the humidity. Continuous drainage means you don’t have to worry about draining the storage tank where the air moisture is collected; you attach a hose to the unit and it automatically drains into your sink or garden, depending on where you place the hose.
What if the dehumidifier I am considering doesn’t have continuous drainage?
Not all dehumidifiers have continuous drainage; in this case, you will have to manually empty the storage tank where the water collects. If you do decide to opt for a model without continuous drainage, choose a dehumidifier that has a large storage tank capacity so you won’t have to worry about it overflowing. You might also want to buy a model that has automatic shut-off that will turn the unit off once the storage tank begins to become too full.
What if I plan on using the dehumidifier in a cold climate?
If your dehumidifier will regularly be used in temperatures under 65 degrees, you’ll want to invest in a unit that has anti-frost sensors that reduce the chance of frost developing within the unit and cycles the air at a faster rate.
Will I have to replace the air filter?
Depends. Most units have an air filter that traps small particles, and these will need to be either replaced or washed regularly. You can buy a unit that has removable filters that can easily be washed, cleaned, and replaced.
Do dehumidifiers require a lot of energy?
While a humidifier will necessarily consume energy, especially when used for long periods of time, there are many models available that don’t use a lot of electricity. Look for Energy Star-rated products, which mean that they have passed Energy Star’s energy standards, which are fairly rigorous. Another thing to look for is whether or not the dehumidifier’s fan runs constantly, or only when it’s used. Some dehumidifiers have fans which are always running, because it helps the dehumidifier monitor air moisture levels at all times. Others only have fans that run when the entire unit is running, so you will save more energy. Using a dehumidifier may actually reduce your energy consumption because it means you can run your air conditioner less, on higher temperatures. Humid air feels a lot hotter than non-humid air; there is as much as a 6 degree difference in your perception of air temperature depending on the humidity in the air; in zero relative humidity, a 75 degree day can feel like 69 degrees, and in 100% relative humidity that same day will feel like 80 degrees. So, by removing excess humidity, you can keep your home cooler and have less need for air conditioning or fans.
Are dehumidifiers loud?
How loud a dehumidifier is depends on the quality of the dehumidifier and how well it is manufactured. All dehumidifiers will make a little noise; it is comparable to the noise produced by an air purifier or the fan in your shower. The larger your dehumidifier, the louder it will probably be, though very high-quality humidifiers can be as quiet as a low-quality, smaller unit.
How do I use my dehumidifier?
Once you have chosen and purchased a dehumidifier, you will want to use it effectively. Make sure to place the dehumidifier in an area where the vents are exposed so air can circulate freely in and out of the unit. The vents on your humidifier should be no less than 6 inches from a wall or other obstruction. When you first use your dehumidifier, set it at the highest possible setting; you can adjust this later, but it will help stabilize the air. Make sure that you check the air filters regularly, and wash or replace as needed.







