If you’ve had the same central air conditioning system for the past ten or more years, it is likely that the system is on the brink of a breakdown.  Doing research into system replacements could save you from a sweltering home in the hot Chicago summer months.  The following tips can help you find the right air conditioner to maintain comfort, increase efficiency, and improve the value of your home.

Choose an energy efficient model

The efficiency of an air conditioner is based on the seasonal energy efficiency ration (SEER) rating.  The higher the SEER rating, the more efficient; air conditioners sold today have mandatory SEER ratings of 13 or above.  Look for a unit with an ENERGY STAR® seal, as these air conditioners meet the strict U.S. Department of Energy and U.S. Environmental Protection Agency standards for efficiency and quality and are at least 14% more efficient compared to similar models. 

Get the right size

An air conditioning system works best if it is the right size for your home, so bigger does not necessarily mean better in terms of central air systems.  A system too large will frequently cycle on and off and will not properly dehumidify the air in your home.  A system that is too small will fail to keep your home comfortable on the hottest summer days.  You can leave it to a qualified contractor to calculate the size that is needed for your home based on a variety of factors including: the volume of the space to be cooled, size and number of rooms; number and locations of vents, duct sizing; number, type, location, and orientation of windows and doors; and insulation levels in the walls, roof, basement, and other areas.  When contacting a contractor, make sure to ask for this calculation—called “manual J”—by name. 

Ensure proper installation

You want your new, high-efficiency air conditioning system to perform at its best, which means it is properly installed in your home.  First, check references to make sure a reliable contractor is doing the work.  A good contractor will spend a good bit of time inspecting and evaluating your home’s heating and cooling needs.  Next, make sure that your contractor has correctly connected and sealed the duct work.  Also be sure that the air conditioner has the refrigerant charge and air flow rate specified by the manufacturer.  Finally, check that the outdoor condenser has been properly placed in a shady location if possible, and is not located under a deck, porch, or other structure that would limit air flow on all sides of the unit.   

Before you start

It is a good idea to make sure that your home is correctly sealed and insulated before you start investing in new home heating or cooling equipment.  Proper air sealing will allow you to get the best results from a high-efficiency air conditioning system.