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Green product watch: Best dehumidifiers 6/12
(This article is adapted from the June 2012 Consumer Reports magazine.)

Got that clammy feeling? In Consumer Reports’ tests several dehumidifiers were tops at sucking moisture out of steamy spots that can breed mold and other allergens.

The ideal indoor relative humidity is between 30 to 50 percent. At higher levels mold can grow. For the majority of persons, undisturbed mold does not pose serious health risks, according to the Centers for Disease Control. But the government says mold can be “a greater hazard for persons with conditions such as impaired host defenses or mold allergies.”

If you have only a minor outbreak in a very small area, you may be able to contain it without buying a dehumidifier. You can use a stiff brush, a non-ammonia detergent, and hot water to scrub mold off non-porous surfaces. To get between edges or tiles, use a stiff-bristle toothbrush or grout brush.

You can also make a paste of baking soda and water and brush with that. Remember to ventilate the room where you’re working, wear gloves, and use a protective mask, since mold spores can be inhaled.

New energy efficiency standards

Dehumidifiers work by using a fan to pull air over two sets of refrigerant-filled coils, which pull moisture from the air and drip it into a tank. Different models vary according to how many pints of moisture they can remove in 24 hours. In Consumer Reports’ tests, some models came much closer than others to the humidity levels that were set on the humidistat; some used less energy or ran more quietly; and some models handled simulated power outages better than others.

As of October 2012, federal energy efficiency standards for dehumidifiers will become roughly 20 percent stricter, on average. Energy Star models typically will have to capture about 4 pints of water for every kilowatt-hour of electricity used. That could save you about $20 per year, though prices could rise by up to $40 to cover the cost of better airflow and other improvements.

Large capacity models already approach the new standards and tend to be the most energy efficient, removing up to 75 pints per day. They can also handle a wider range of humidity levels with little or no additional noise. And you may be able to run a large model on a lower, quieter setting. Some manufacturers are scaling back on small units, which remove fewer than 45 pints per day and have been least impressive overall.

What to look for

The best large models –for big or very wet spaces-- remove moisture quickly and efficiently in the toughest situations, such as an especially wet basement. Watch video buying guide.

Frigidaire’s FAD704DUD 70-pint dehumidifier at $240 topped the ratings and makes less noise than most models. Haier’s DE65EK-L at $200 was also recommended though it made more noise. The Soleus Air SGj-DEH-70-2 at $225 did almost as well as the Frigidaire.

For small or damp spots, a medium-capacity model will do well with less cycling than a larger model, according to the industry. A Frigidaire model also topped this group with its FAD504DUD at $200.

Time your purchase

New models appear in late spring and early summer, and most sales and in-store promotions occur from June through August. You might find closeout deals in the fall and early winter.

Fix existing problems

Even the best dehumidifier may not work effectively if too much outside moisture seeps into your home. Before you buy a humidifier, see what’s causing the dampness. A sump pump or exhaust fan can help keep relative humidity within the optimal 30 to 50 percent.

Check that gutters aren't clogged and that downspouts are directing rainwater at least 3 feet away from the house. Grade your property so that rainwater flows away from the foundation. Keep the duct for your clothes dryer properly vented to the outside, making sure that it isn't clogged or leaking. Run an exhaust fan or open a window when showering, and squeegee or wipe down shower walls afterward. When cooking, use a range hood that vents outdoors.

In the basement, check the plumbing for leaks and condensation. For a damp rather than leaky basement, applying a waterproof coating (when walls are dry) may help. Use silicone caulk to seal small gaps in the foundation, and hydraulic cement for cracks. More extensive problems may require excavating and waterproofing exterior foundation walls, and installing drains outside.

Related links

Dehumidifiers buying guide.

How to control a mold outbreak. 10/11
Copyright © 2003-2012 by Consumers Union of United States., Inc., 101 Truman Avenue, Yonkers, NY 10703, a nonprofit organization. No downloading, transmission, photocopying, or commercial use permitted. Visit www.GreenerChoices.org.