Why do Air Conditioner capacitors go bad now and then?!
There are many reasons for that. I mention some of the most important ones in brief:
1- Voltage spike or fluctuation.
2- Old or defective compressor.
3- High ambient temperature.
4- Dirty condenser coil (result in the compressor draws more amperage than normal)
5- Any blockage in the system
6- Dirty capacitor
7-Ending the lifespan of the capacitor.
8- Thermostat or ambient temperature sensor in Indoor Unit goes bad
9- Compressor oil acidity.