The AC's capacitor is used to help its compressor or fan motor turn on. Without the capacitor, the AC's motor won't be able to start rotating. So how does the capacitor work, anyway? And why is it needed? Whether it's your AC's blower, condenser fan, or compressor—all of these devices use electric motors to run. One thing. The AC's start capacitor gets the motor running, while the run capacitor helps keep the motor running smoothly. In the permanent split capacitor (PSC) motors found in most AC units,. One of the most common issues of an AC system is a bad capacitor. Here are a few different signs that your AC's capacitor might be bad: 1. Your AC's blower won't turn on 2. Your AC's. Discharging your AC's capacitor is important an important step if you're going to be testing or replacing the capacitor. Discharging a capacitor. If you have a multimeter with a capacitance testing function, then you can test your AC's capacitor. CAUTION: Capacitors contain dangerous amounts of electrical charge, so.
