lifespan of an air conditioner lifespan of an air conditioner lifespan of an air conditioner lifespan of an air conditioner lifespan of an air conditioner last a decade or more last a decade or more lifespan of an air conditioner lifespan of an air conditioner lifespan of an air conditioner lasts between 10 and 15 years. lifespan of an air conditioner lifespan of an air conditioner lifespan of an air conditioner lifespan of an air conditioner lifespan of an air conditioner last about 15 years lifespan of an air conditioner furnace lifespan lifespan of an air conditioner lifespan of an air conditioner A/C unit’s lifespan lifespan of an air conditioner lifespan of an air conditioner A typical system lasts 10 to 15 years lifespan of an air conditioner lifespan of an air conditioner Fifteen years