An air conditioning tune-up is a routine maintenance check that is performed on an AC unit to ensure its optimal performance. This checkup includes inspecting and cleaning the air filters, checking the refrigerant levels and pressure, lubricating the moving parts, inspecting the electrical connections and controls, and testing the thermostat. The purpose of an air conditioning tune-up is to identify and fix any potential issues before they turn into major problems, and to ensure that your AC unit runs smoothly and efficiently throughout the summer months. It is recommended to have an air conditioning tune-up done once a year to keep your unit functioning properly.