Should Capacitors Get Hot?

In general, things get hot when current flows through them. A properly-connected capacitor shouldn't have current flow in a DC circuit, so it should not warm up.

What causes a capacitor to get hot?

1. In power electronic circuits, electrolytic capacitors are exposed to high temperatures and high ripple currents. When charging and discharging currents flow through a capacitor losses are caused by ohmic resistance which causes an increase in temperature.

What happens when a capacitor overheats?

These capacitors will occasionally fail, causing a compressor to fail to start. Overheating is a primary cause of a failed start capacitor. Start capacitors are not designed to dissipate the heat associated with continuous operation; they are designed to stay in the circuit only momentarily while the motor is starting.