SEER RATING: When selecting a new system, pay close attention to the SEER rating or seasonal energy efficiency rating of the air conditioner. It's a number that describes how well air conditioning equipment works. In fact, the higher the SEER rating, the more efficient the system will be and the more you'll save on your energy bill. For central air conditioners, the national minimum energy-efficiency rating requires a 13 SEER rating. But in order to achieve maximum energy efficiency, you should look for models that have a SEER of 15 or higher. Lennox offers the Dave Lennox Signature® Collection XC21 air conditioner, the quietest and most efficient central air conditioner on the market. With a SEER rating up to 20.5, it can reduce monthly energy bills by up to 60 percent.

SOUND LEVEL: Older cooling units tend to be noisy and can produce sounds as high as 82 decibels, which is about as loud as an alarm clock. An important consideration that homeowners tend to overlook is that today you can find units that are designed to help decrease noise while providing total comfort. Product lines such as the Dave Lennox Signature® Collection air conditioners and heat pumps from Lennox quietly deliver a superior level of comfort by using exclusive sound-absorbing SilentComfort™ technology. In fact, the Dave Lennox Signature Collection XC15 air conditioner is the quietest central air conditioner you can buy with sound levels as low as 64 decibels, which is about the sound level of normal conversation.

SIZE: Bigger isn't always better when it comes to air conditioners. If the unit is too large, it may turn on and off too frequently and will not effectively cool your entire home. Also, if the unit is too small, it will run too often and may be unable to cool your home sufficiently on the hottest days of the year. To help you determine the proper size and correct air conditioning cooling capacity for your home, enlist the help of a reputable home cooling contractor.