The level of relative humidity in your home is essential because it affects your comfort level and health. Besides feeling sticky and soggy, higher humidity levels promote mold growth and may worsen conditions for allergy and asthma sufferers.
All portable air conditioners have some impact on the relative humidity of a room. However, since dehumidifying is not the primary purpose of a portable air conditioner, it’s not as effective as a dehumidifier. To have the most significant impact on lowering the relative humidity levels in a room, a portable air conditioner must have a dehumidifier mode.
Before understanding humidity, we have to do a quick refresh of some elementary school science.
While over 70% of the earth's surface is water, that is not enough to sustain life in the other 30%, where there is no water. The water cycle is the vehicle that ensures life can flourish anywhere on the planet.
Heat provides the energy needed to break the bonds which hold water together, allowing it to turn from a liquid into a vapor. This process is called evaporation. When that water vapor condenses, clouds form.
Eventually, the condensing vapor becomes too heavy to remain suspended in the air, and it falls back to earth as precipitation. That precipitation collects as water on the earth’s surface, where heat once again turns it into vapor, continuing the cycle.
Humidity is a measure of the naturally occurring water vapor that is present in the air.
The higher the temperature, the more vapor will move around and resist condensing. In short, hotter air can hold more water vapor (before condensing) than cooler air can. Relative humidity simply tells us how full the air is of water vapor at a specific temperature.
While the percentages for ideal relative humidity levels may vary – even among government organizations – several studies published on the National Center for Biotechnology Information website conclude that between 40-60% is the "optimal range for reducing growth opportunities for viruses, bacteria, and fungi." If you want the healthiest home environment, strive to keep your relative humidity between 40-60%.
Now that we understand humidity and relative humidity, its importance to sustaining life and what the ideal levels should be in your home, there is one more bit of information needed to understand how a portable air conditioner can affect indoor relative humidity levels. Dew point.
A dew point is a specific temperature the air needs to be at for water to condense. When the vapor in the air condenses back into water, the humidity level drops.
The primary purpose of a dehumidifier is to remove water vapor from the air. The way it accomplishes this task is relatively simple.
The primary purpose of a portable air conditioner is to cool the air. The way it accomplishes this task is very similar to how a dehumidifier works.
Dehumidifier: Is designed to remove moisture from the air to decrease the relative humidity without affecting the temperature of a room.
Portable air conditioner: Is designed to lower the temperature of a room. While it does remove some moisture, that is not its primary purpose, so it is not as effective at lowering the relative humidity of a room as a dehumidifier.
While many portable air conditioners are only designed to cool the air, they can also be manufactured to dry the air or just move the air. A model that can function as a dehumidifier will feature a dry mode or a dehumidifier mode. Checking to see if your portable air conditioner has this mode is the easiest and quickest way to know if your model has a dehumidifying feature.
Whynter Dual Hose Portable Air Conditioner
This dual hose unit can quickly cool down a room that is up to 500 square feet. The dehumidifier has a maximum capacity of 71 pints per day, and the fan has three speeds so you can fine-tune your comfort level.
Where to buy: Sold by Amazon, Home Depot and Wayfair
BLACK+DECKER Portable Air Conditioner
You can cool smaller spaces (up to 250 square feet) down to 65 degrees with this BLACK+DECKER unit. It features a sleep mode for quiet operation at night, a fan mode and a dehumidifier mode.
Where to buy: Sold by Amazon
LG Electronics Portable Air Conditioner with Dehumidifier
For versatility, this LG portable air conditioner has two cooling and fan speeds as well as a 24-hour timer so you can create a customized cooling schedule. The removable filter is washable, and the unit features a light that illuminates when it is time to clean the filter.
Where to buy: Sold by Home Depot
Toshiba Portable Air Conditioner with Dehumidifier
The dehumidifier feature on this portable air conditioner can remove up to 4.27 pints of moisture from the air each hour. It has four wheels for ease of portability, a 24-hour timer and a sleep mode for convenience and comfort.
Where to buy: Sold by Home Depot
SereneLife Portable Air Conditioner Unit
If budget is your primary concern, this air conditioner is more affordable than comparable models from other manufacturers. It features four modes – cool, dehumidifier, fan and sleep – and can be operated by remote if desired.
Where to buy: Sold by Amazon
Allen Foster writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.
