If your air conditioner is not getting your home as cool as you would like, there are a couple of reasons. First, you may need to change your filter. Second, you may need to clean out the outdoor condenser. If these two things don't work, you may need to call a professional for service. If it is extremely hot outside, you may not need service. It might just be too hot outside for your AC to keep up with the heat. All air conditioners have a filter. It is located inside the home, often behind a grill in the hallway.