Noises generally indicate a problem. If your system is making an abnormal noise, you should generally call a professional. You should also pay attention to how your system is functioning. If it’s running non-stop or blowing out air that is the wrong temperature, there is most likely a problem. A particularly high bill could also be a sign.

If you have any of these problems, simple wear and tear could be to blame. You will most likely experience more issues toward the end of your unit’s life. Other issues⏤such as a bad part⏤can usually be prevented with maintenance.