Keeping It Cool
Installing an air conditioner in your living room, bedroom or home office can help you keep cool when the temperatures start to rise. Whether you choose a window, portable or built-in wall unit, an air conditioner can help keep your home comfortable through the warm summer months.
Air conditioners must do three things to properly cool an area:
• Lower air temperature
• Remove air moisture
• Filter the air
The air conditioner must be the right size to perform all of these functions and successfully make the room cool and comfortable.
Selecting Your Air Conditioner
Size does matter when choosing an air conditioner, so it's important to get a unit with the cooling capacity to handle the room where it will be installed. A unit that is too small may not be able to cool a space efficiently, while an oversized air conditioner in too small a space will cycle on and off, wasting energy and decreasing the unit's ability to adequately dehumidify the room.
While there are many different types and sizes to choose from, not all air conditioners are created equal. As you shop for your new air conditioner consider the following:
• Where and how the air conditioner will be installed or used?
• How large is the room where you plan to install your new unit?
• What special feature options are most beneficial to you?
• Will you be installing your new air conditioner by yourself or will you have help?
Window units are by far the most popular. Models can be installed in most single or double-hung windows and typically come with accordion panels that allow for a secure fit. Some models can fit in sliding windows. They do require a support of some kind, such as a wooden plank or a specially designed shelf that can be attached to the exterior of your home for dedicated reinforcement.
Installing a window unit is an easy DIY project. Make sure you measure the inside window dimensions before you shop.
Advantages and Disadvantages
• Easy to install
• Easy to remove and store
• Heating and cooling units available
• Blocks window where installed
|Portable air conditioners or freestanding units can be used to cool a specific area in a home such as a bedroom. They don't require any permanent installation and instead have a standard window venting kit for the exhaust hose. Many portable units are mounted on casters so you can move them freely from room to room. They come with a large, flexible hose that is attached to a window for exhausting hot air, much like a clothes dryer is vented.|
Most portable units have reservoirs that need to be periodically emptied, though some also come with optional hookups for a drainage hose. Some new models evaporate much of the moisture and exhaust it, greatly reducing the frequency of need to empty a container. Portable air conditioners can also be used to support any central HVAC (Heating, Ventilating, Air Conditioning) systems.
When choosing the right portable air conditioner be sure to measure the room size (length x width), match the room size with the BTU and check electrical requirements.
Advantages and Disadvantages
• Easy to set up or relocate
• Can use in multiple rooms
• Less efficient
Built-in air conditioners can be installed in your wall for permanent placement and operation. These units often provide both cold and hot air operation for more versatile use. They are a great solution for rooms or additions to your house that may not be connected to the central heating and air conditioning system.
Wall units require opening a hole in an exterior wall. They don’t take up window space, and they allow for a more airtight and secure fit. Many window models can be installed through the wall, just add a frame to support the unit. Smaller units can be installed by handy do-it-yourselfers. Larger wall units may require professional installation.
Advantages and Disadvantages
• Models with heat function available
• Location flexibility
• Option to use wireless thermostat
• More expensive
• More involved installation
• Additional parts may be required
Energy Efficiency and BTUs
EER - Energy Efficiency Rating
All new room air conditioners are required to carry an EER, or Energy Efficiency Rating, which ranges from 8 to 11.5. The ranking is important for consumers because air conditioners with higher EERs yield the most savings in monthly electric bills.
The higher EER also helps the environment by reducing greenhouse emissions. Check the yellow Energy Guide label on new room air conditioners when you’re shopping. A rating of 10 or higher will produce the most in energy savings, though these models are likely to cost a little more.
BTUs - British Thermal Units
When it comes to evaluating the energy efficiency of a room air conditioner, there are two pieces of information you should pay careful attention to – the unit’s EER and its BTU (British Thermal Units) rating.
The BTU rating is a number that essentially tells you how quickly and effectively a unit can cool the room where it is located. They generally range from around 5,000 BTUs to more than 20,000.
Consult the BTU calculator to the right for some general guidelines. The EER rating is determined by dividing the number of BTUs by the air conditioner’s wattage.
Size and Efficiency
Choosing the right BTU for your room size, while integrating all other outside factors, like ceiling height, type of room insulation and type of climate, sun exposure and location, will give the most energy-efficient cooling system.
Selecting the right air conditioner begins with making a few simple calculations. First you’ll need to determine the size of the area where the unit will be installed. If the room is square or rectangular, simply measure the length and width of the room and multiply them to get your square footage. When cooling two adjacent areas, determine each space separately then add the totals.
Once you have determined the square footage of the room consult the BTU calculator for the correct amount of BTUs needed. Tailor the unit to the room. For example, if the room is:
• In a sunny location - increase BTUs by 10%
• In a shady location - decrease BTUs by 10%
• Occupied by more that one person - add 600 BTUs for each person
• A kitchen - add 4,000 BTUs
Room air conditioners that feature automatic timers or programmable thermostats allow you to set the unit to run on its own for maximum convenience and efficiency. Timers are a simpler and less costly alternative to programmable thermostats. Just set the time you want the AC to start or stop. Timers allow you to keep your home cool, without continuously running the air conditioner while you’re away.
Digital controls give you more control and precision over the operation of your air conditioner. Many units with this feature will allow you to specify the exact temperature you desire. The ability to control temperature by degrees—instead of with HIGH or LOW settings—allows for more comfort and wastes less energy.
Models that include a remote control allow for easy temperature adjustments from anywhere in the room.
Designed to operate at quieter levels, these units make it easier to carry on a conversation or watch your favorite television program without needing to compete with the noise of your air conditioning unit.
Variable Fan Speeds
More speed settings give you greater control of air flow. The lower settings also help save money.
Slide-out filters make it easier to clean and remove dust and other allergens from the air. Regular maintenance will extend the service life of your air conditioner and help it operate at full efficiency.
Sleep Setting/Energy-Saving Setting
These allow the unit to operate at a very low setting, saving on energy costs while making the room more comfortable for sleeping.
Installation and Maintenance
All room air conditioners function pretty much the same, although energy savings and cooling capacity can vary by brand and model. Like central air conditioners, room air conditioners cool and dehumidify the room air by extracting heat and moisture, and then return the air to the room.
When it comes to maintaining your unit be sure to:
• Clean filters on regular basis to ensure optimum performance
• Install foam weather stripping around window units to keep cool air inside
• Remove and store away window units during winter months
• Follow manufacturer's instructions for proper removal and storage
Air conditioners can be heavy and awkward to handle. Make sure you have assistance when handling heavy units to avoid any injuries. Also use caution when installing them on the upper levels of your home. Always follow the manufacturer's instructions for safe and proper installation.
Be aware of the room's electrical requirements before selecting your air conditioner. There are three electrical requirements to consider before making a purchase.
1) Is the outlet within reach of line cord?
2) Voltage requirements
3) Amperage available
UL requires that only 115-volt model using more than 7.5 amps be connected to a standard single outlet. 208/230-volt models require one of three branch circuit power supplies.