If the spring showers haven't already forced you into a dehumidifier purchase, the dog days of summer to come should. New models often appear in late spring and early summer, so be on the lookout for sales and in-store promotions. Delay too long and you might have to settle for a less-than-optimal dehumidifier—either a unit that's sized incorrectly to your needs or one that comes up short in Consumer Reports' dehumidifier tests.

A hot summer forecast—and air-conditioner prices that are going up with the mercury—could mean an early run on window units. But you needn't wait and sweat it out: Consumer Reports testers just named 15 top room air conditioners that include several small and mid-sized models priced at around $200 or less. But the volume of some we tested could keep you up at night. And a few might have you struggling with less-than-intuitive controls.

The Nest Learning Thermostat is already one of the smartest devices on the market, learning your habits and controlling your home's climate accordingly. Thanks to Nest's WI-Fi capability, the $250 gadget can also receive IQ-enhancing software upgrades, including a batch this week designed to conserve energy during the cooling season.

This month while some regions of the country are flirting with temperatures in the eighties others are still digging out from snow. But summer will be here all too soon so it's a good time to make sure your air conditioner is in working order before a real heat wave hits. Air conditioners fail because they're installed wrong, serviced poorly, or not maintained properly. Some problems you can fix yourself but others may take a call to a professional. Here are the five most common problems with air conditioners and how to troubleshoot them, according to the federal Department of Energy.

As a result of the last-minute enactment of the Taxpayer Relief Act earlier this year, six common energy-efficient upgrades you may have made to your home in 2012 or plan to make this year are eligible for a federal tax credit. Replacement windows and doors, new roofs and upgrades to heating and ventilation systems all qualify for a credit of up to $500. The improvements must be made to your existing home and principal residence, new homes do not qualify. Here are the details, according to Energy Star.

High-definition screens, web-enabled controls, smart capabilities—you'd expect to find these features on the latest televisions and tablets. But increasingly they're also on thermostats, as manufacturers look to up the wow factor of these relatively mundane products, while also making them easier to use. These features, which were on some of the top-rated thermostats from our latest tests, are also on new models introduced by Lennox and Honeywell at the International Builders' Show.

With winter temperatures expected to be near normal, most households will be spending more to heat their homes than last season when temperatures were mild. The pocketbook pain will be especially acute for the six percent of homes that heat with oil—average expenditures for those households are forecast to be higher than any previous winter on record, according to the U.S. Energy Information Administration, and almost 20 percent more than last year.

In Consumer Reports' recent report on programmable thermostats, the Nest Learning Thermostat earned a spot on our recommended list, thanks to its clear display, relative programming ease, and Wi-Fi capability, which allows you to control the device from a computer or smart phone. But several programmable thermostats fared better overall in our Ratings. The second-generation Nest, which launches today, comes with several design enhancements and the promise of improved control and compatibility.

In a milestone in energy-savings, one million homes have been weatherized since 2009 as part of the Energy Department's Weatherization Assistance Program. Financed by the American Recovery and Reinvestment Act, the program helps lower-income households, which studies show spend significantly more of their total income on energy bills than other households. But homeowners who don't qualify for the program can use the same techniques to seal the leaks in their own homes and reap the rewards.

Programmable thermostats can lower energy bills by roughly $180 a year, yet only half of thermostats installed in today's homes are programmed to lower temperatures when the house is unoccupied or at night, according to a study funded by the Department of Energy. The reason, says other studies, is that people find programmable thermostats too hard to use. And in Consumer Reports latest tests of 30 energy-saving thermostats, we did find some that were so difficult to set that you might give up in frustration. Fortunately, some others were simple to adjust.

Electric space heaters are a cheap way to chase away the chills—and they don't come much cheaper than the $25 Optimus H-5210 sold at major retailers like Amazon, Sears, and Walmart. But it was the only electric heater in our tests of 19 models that set our test cloth on fire. We contacted Optimus, and test results it sent us also showed a potential safety problem with this model. It claims to have fixed the problem on 2012 models. But we bought our heaters, 2011 models, in early summer, and there is no way to tell the model year from the box.

Isaac in all its guises—hurricane, tropical storm, tropical depression—dropped a lot of rain on residents of the Gulf Coast leaving behind a soggy mess. The next threat for affected homeowners is mold, which can ruin home furnishings and pose problems for residents with allergies, asthma, and compromised immune systems. To keep it in check, homeowners should attack the problem within 24 to 48 hours.

With much of the country still under a blanket of sweltering heat, chances are you still have your dehumidifier running full tilt. But dry, cool air will be here before you know it, and retailers have already stocked up on humidifiers. Consumer Reports recently wrapped up testing of nearly 30 models from brands like Crane, Essick, Hunter and Vicks. About a dozen made our winner's list—not a bad percentage as product categories go—though we also found several models with poor performance and added costs.

The maker of EdenPure heaters has been told to discontinue its claims that the portable heaters are safer, superior and save more than other heaters. Suarez Corp, the manufacturer, can continue to boast that the heaters are "made in the U.S.A." after a review by the Electronic Retailing Self-Regulation program. Consumer Reports recently included an EdenPure model in its tests of portable heaters but it didn't make the list of eight top picks.

Sears, Roebuck and Co. and Kmart Corporation recalled 795,000 Kenmore dehumidifiers because the units can overheat, smoke, melt and catch fire, posing a fire and burn hazard. Sears has received 107 reports of incidents, including three smoke inhalation injuries and more than $7 million in property damage.