A dehumidifiers purpose is to lower and control the humidity in the air, thus eliminating odors, providing a more comfortable environment and decreasing the chance of mold growth. When humidity levels reach 60% and above in a home, mold growth is almost certain as well as other potentially harmful and costly issues. The ideal range of humidity within a home is between 35 to 45 percent. This will also limit populations of most pests including clothes moths, fleas, cockroaches, woodlice and dust mites. By their operation, dehumidifiers produce an excess of water which has been removed from the conditioned air. This water, usually called condensate in its liquid form, must be collected and disposed of. Some designs, such as the ionic membrane dehumidifier, dispose of excess water in a vapor rather than liquid form.
Choosing the right dehumidifier can be a daunting task especially because most units sold in big home stores aren’t big enough to compensate for the area in which they are placed. This will cause a unit to constantly run and never be able to handle the square footage of the area and make it impossible to regulate the humidity to the appropriate level. Most basements which are 1500 square feet or more will need a bigger and more energy efficient units to achieve the desired relative humidity level. A dehumidifier should remove 3 pints of water per kilowatt hour at 80°F and 60% RH, which is the industry standard. Units with even greater removal rates, from 5.5 to 6.8 pints of water per kilowatt hour, will generally cost between $1500 to $2200. They will not only pull a greater amount of water, but easily keep the RH levels at the desired rate while using a very limited amount of electricity. So when shopping for a dehumidifier, do not get sold on price, but how many pints of water can the unit pull while understanding the limitations of the unit itself against the size of the room it is being placed in.