Every summer before the weather is too hot and humid, I contact the AC repair company to perform a full service tune up on my AC machine. I have had this AC serviced regularly performed each year, because I think it is an important part of seasonal maintenance on the system. A tune-up on the AC machine is much like a tune-up that will be performed on a car. All of the parts of the machine are examined from the top to the bottom. A full-service ac tune up should include replacing the air filter, cleaning the drain line and condenser coils, and checking for faulty or damaged electrical parts. The full service inspection completed by the local company includes 50 different areas. My wife and I received a paper at the end of that service and the technician has to check off each individual spot. All of the individual parts of the heat pump and AC unit are inspected and each space has a comment section for anything that might be out of the ordinary. There is a 30-day warranty on the service tune up and if there are any problems that come up during that time, there is no fee for the labor. Regularly scheduled tune-ups can really prevent a lot of minor problems from becoming a major hassle. As the machine ages, I know that the mechanical and electrical components will run down and wear out. That is one of the biggest and most important reasons to hire a trained professional to inspect the system every year.