Models that scored excellent or very good in our noise tests are so quiet that the only sound you might hear is the fan running. Air conditioners that scored fair for noise could disturb light sleepers when set on low, and are distracting to all when set on high. Factor in the Window Location Window air conditioners generally do a better job blowing air in one direction. That can be a problem if your window isn't centered on the wall. To uniformly cool a room, you'll need to direct air to its center, so check whether your A/C needs to blow air to the right or to the left. Some have fan arms that swivel. To get the most from your window air conditioner it must be properly installed. Most units are intended for double-hung windows. If you have casement windows, you may want to consider a through-the-wall air conditioner. Make sure your window unit is level so it drains correctly. And move any heat-generating devices such as a TV or lamp away from the unit. Make sure you can easily access the filter for cleaning, something you'll be doing frequently to keep the unit in tip-top condition.

Some air conditioners have gotten smarter, allowing you to control and adjust them from your smartphone. You can often interconnect them to other cooling units in your home. Some air conditioners have longer warranties. When you're buying a new unit, check the manufacturer's website for information and ask the retailer about the warranty for that model and brand. Sizing Up Your Options Before you consider price and features, start by determining the size of unit you need for the space you want to cool, as well as where you’ll place the unit. Window air conditioners have cooling capacities ranging from 5,000 to 12,500 British thermal units (Btu). As a rule, an air conditioner needs 20 Btu for each square foot of living space. But don't buy by Btu alone. Energy Star recommends you make allowance for other considerations—such as the height of your ceiling, where the unit will be placed, and the size of your windows and doorways. • If the room is heavily shaded, reduce capacity by 10 percent.

• If the room is extra sunny, increase capacity by 10 percent. • If more than two people regularly occupy the room, add 600 Btu for each additional person. • If the unit is used in a kitchen, increase capacity by 4,000 Btu. Get more Consumer Reports information on how to beat the heat here. Which Model is Right for You? Some small window units cost less than $200, which makes them a tempting proposition—but only if you need to cool a very small space. If you need to cool a larger area, you’ll want to focus your search on units that better match your square footage. Nearly all the window units we tested meet the latest Energy Star standards, which require them to use 15 percent less energy than units without that certification. Standout models had quiet operation, convenient controls, and worked under brownout conditions. Check our Air Conditioner Ratings to see to how they stacked up. Small—Capacity ranges from 5,000 to 6,500 Btu/hr. Cools roughly 100 to 300 square feet.

These units are the smallest, lightest, and least expensive, but they can’t adequately cool a room measuring more than 300 square feet. Medium—Capacity ranges from 7,000 to 8,200 Btu/hr. Cools roughly 250 to 400 square feet. Prices start creeping up, and their size and weight can make them harder to install and remove for winter storage. Large—Capacity ranges from 9,800 to 12,500 Btu/hr. Cools between 350-650 square feet. small window ac unitsBest for cooling a large room, but the bulk and weight make these models awkward and difficult to install.prices on window ac units Window Air Condioner Ratingstop rated central ac unit Portable air conditioners are intended for homes in which window configurations or building regulations prevent installation of window units.

The portable air conditioners in our tests range from 5,000 to 15,500 Btu. But don't compare portable and window air conditioners by that measurement alone. Our latest tests found that portables aren’t as good at cooling as manufacturers claim. Plus, they’re pricey and use more energy than similarly sized window units. They tend to be noisier than window-mounted units. And while technically “portable,” their 50- to 80-pound weight can make them cumbersome and ungainly to roll across carpets or thresholds. Portable Air Conditioner Ratings Split ductless is a smart way to add air conditioning to a limited number of rooms without having to open up walls to install ductwork—as you would with a central-air system—or install and remove multiple window units each year. In our past tests, all did an excellent job cooling and were much quieter indoors and out than window air conditioners. Indeed, on the low setting they were barely audible. Split ductless is more expensive than window or portable units (and professional installation is recommended), but is less expensive than central air if you are cooling only a few rooms.

However, if you are looking to cool the majority of your home, a central-air-conditioning system is probably the more cost-effective choice. Cost: $1000 and up. Consumer Reports' Air Conditioner Overview Interactive Video Buying Guide For more, watch our interactive buying guide below. You can skip to chapters based on your interests, such as portable air conditioners, split ductless air conditioners, and other topics. Smart Features to Help You Chill Out All the units in our Air Conditioner Ratings do an excellent job of cooling. They also come with convenient features like digital displays, built-in timers, and remote controls. Some units have touchpad controls, and a few change the direction of the airflow automatically to better disperse cool air throughout the room. Look for air conditioner features that affect performance and efficiency.You are here » Room Air ConditionersTilt your window unit slightly lower outside to aid draining. Not only does air conditioning lower the temperature inside your home no matter how hot the day, but it also removes humidity from the air.

As the cold refrigerant inside your window air conditioner circulates through the evaporator (an indoor cooling coil) the warm air inside your home creates condensation -- like steam on a bathroom window during a shower. Newer units are designed to hold much of this water in the pan, where the fan slings it across the condenser (the outdoor coil) to lower the unit's temperature and increase its efficiency. Some units drain continuously, however. To help either drain better, take whichever measures you find necessary. Unplug the window air conditioner, and ensure it is stable. Have an assistant help you during your work; she can steady the air conditioner and help remove it from the window if it becomes necessary. Check the window unit to determine if it's level or slanted toward the ground outside. To aid proper drainage, the rear of the unit should drop about an inch lower than the front. "Eyeball" the air conditioner, working from outside; if it's slanted enough, it should appear obvious.

If it's difficult to tell, lay a carpenter's level across the top. Drop the rear of the unit lower than the front to increase the unit's angle and encourage good drainage. Even newer units that don't drain continuously generally have an overflow drain in case the water level gets too high. To lower the unit's rear, consider the installation method. If the unit sits unsupported in the window, it's generally a matter of pulling it slightly forward to allow the rear to drop. Braces of various kinds may need to be cut and reattached or otherwise lowered to allow the rear to drop. Find the drain hole or plug designed to expel excess water. On constantly draining units (usually older or very large units) the hole is generally underneath the exterior portion of the unit and may be very small. Window air conditioners designed to retain water may have a hole on the side instead, so when the water reaches a given level it drains away. Alternatively, you may find a cap underneath the unit that allows you to pour off water before recapping.

Unplug the drain hole if you see or suspect it's clogged at or near the entrance. Poke a long, thin wire or even a baby bottle nipple cleaner through the hole, and work it back and forth like you're brushing your teeth. Often this is enough to encourage the water to drain. Pull the unit from the window, remove the outer casing if necessary and set the unit on a clean surface. Lay a thick cloth over the switches and fan motor, and tilt the air conditioner slightly to encourage water to flow away from these electrical parts. Spray the unit, using a low-pressure stream, directing the flow from the inside of the coils out to remove excess dirt and debris. Remove the base pan, into which the condensation drains, to clean the pan or the internal drain system. Unscrew or pull to unclip the base pan (sometimes called a drip tray) from the bottom of the unit. Scrub with a rag and water from the hose. Alternatively, replace the tray with a new one; if it's rusted or extremely damaged, it may be preventing proper drainage.