Springtime Window of Opportunity for A/C

Enjoy it while you can. Beads of sweat will soon replace the balmy breezes of spring. Better start thinking seriously about home cooling as a major priority. Homeowners and home buyers should know that window A/C units, properly installed, are a practical alternative to sizzling and sweltering.

Window air conditioners can be a low-cost answer, short of installing or replacing a central a/c system, for cooling the home on a room-to-room basis. You can choose which rooms you want to cool and adjust the level of cooling accordingly. But before you open your checkbook, make sure you're prepared to purchase the right unit and install it properly.

Energy Efficiency Rating. (EER) Look for the EER when you are comparing window air conditioners. The higher the EER posted on the equipment, the less electricity it will take to run it - which means you save money on utility bills. A rating of at least 9.0 or higher is currently considered a good EER for home air conditioners.

Cooling Capacity. All AC equipment is rated in BTUs (British Thermal Units). Consult with a knowledgeable sales person in selecting the right capacity for the size of the room(s) you plan to cool. The most scientific calculation is through a cooling load estimate that translates factors including square footage of windows and number of people using the rooms into a BTU rating.

Electrical. Consider your house wiring. A 220-volt circuit is necessary to run a 220-volt unit. Smaller, 110-volt units should be plugged into their own circuits with their own circuit breaker. Consult with a licensed electrician on installing new wiring or circuit breaker.

Installation. Don't try to set an Olympic record by trying to manhandle a large air conditioner. While smaller units are okay for a solo effort, it may require two to three people to install a larger unit in the window. Try to place the window or wall air conditioner where it will be shaded from afternoon sun by a tree or awning. That way it won't have to work as hard to provide cooling. The sash supports the weight of the unit. Heavier units can stress out vinyl windows over time, causing the sash to bow. Make sure the unit is supported in some other way, with struts attached to the window or exterior of the house. The air conditioner should be mounted so that it is slightly tilted toward the outside so that it'll drain condensed water onto the ground and not back into the window. Be sure to block any gaps around the equipment with weather stripping or sections of foam plastic.

Through-the-Wall and Split Systems. This equipment is for those who don't like having their views blocked by a window air conditioner. Through-the-wall units are installed in the wall. They cost about the same to buy but more to install. A split system has the fan and cooling coil installed in an inside cabinet, with the condenser located outside where it won't cause as much racket. Split systems are quieter and have greater cooling capacity than window units.

Maintenance. Unplug the AC and take out its filter once a month for washing during hot weather use. Simple clips or tabs usually hold in the filter. Wash it in a mild soapy solution and let it dry. While you've got the filter out, vacuuming or brush out around the evaporator coils. Be sure you have the AC unplugged during any of the cleaning activities.