The answer depends on a number of factors including how old your air conditioner is. If it is more than 10 years old, it may be time to replace it, regardless of its condition. If it is less than 10 years old, you should consider its condition and how much it costs to repair. Another factor to consider is how often the air conditioner breaks down. If it breaks down more than once a year, it may be worth replacing it. Finally, you should consider the cost of replacement versus the cost of repairs. If the cost of repairs is more than 50% of the cost of replacement, it is probably worth replacing the air conditioner.