Newer energy efficient air conditioners use 30% to 50% less energy to produce the same amount of cooling as air conditioners 20 and 30 years ago. Even if your air conditioner is only 10 years old, you could save 20% to 40% of cooling energy costs by replacing it with a new efficient model. The life on an air conditioner is about 10 to 13 years as it is.  Getting the proper size unit and installation are major elements in determining how well your air conditioner cools your house off.  A too small a unit will not be able keep up on the hottest days.  Also, the location, improper duct installation and lack of insulation,  can greatly affect it’s efficiency.  For air conditioning repair Denver call your HVAC service company.