Most air conditioners are not made to last beyond fifteen years, even with adequate maintenance. At some point, as a homeowner, you will have to replace your air conditioner. Investing in a new AC system is a costly endeavor. However, continuous repairs, which can run into thousands of dollars each time, are often more expensive as you go on. The most important factors to think about are the age of the unit, your comfort, and how much the AC unit costs each month in energy expenses. If your AC unit is over ten years old, can’t keep your home cool, and costs a lot to run, a new system is a smart idea.