Don't wait until your AC isn't working at all and panic! I would encourage you to find your local AC company and sign up for their annual service plan! Guy's AC is who I use and they actually come out twice a year and maintain both of my units. With the extreme Texas heat, these AC units are working NON-STOP! Don't get in a bind! It will make your units last longer I promise!
Also, if you have a home inspection report, look carefully at the AC and ensure it is functioning properly with the differential in temperatures and humidity ranges.
If you have a home warranty on your home, use it! That $75 co-pay is worth it!
Questions? Comment on the blog!