An air conditioner’s life expectancy is affected by many factors. An air conditioner that receives regular AC maintenance will last a lot longer than a car that has regular maintenance. It is also important to consider the quality of the installation as well as the brand of AC conditioner that was used. Certain brands have known issues. We believe that an air conditioner should last around 15 years. However, some air conditioners can still be used for up to 20 years.