A motor capacitor, such as a start capacitor or run capacitor,
including a dual run capacitor, is an electrical capacitor that
alters the current to one or more windings of a single phase AC
induction motor to create a rotating magnetic field. It is used
in air conditioners, hot tub/jacuzzi spa pumps, or forced air
heat furnaces for example. A round dual run capacitor (described
below) is used in some air conditioner compressor units, to
boost both the fan and compressor motors. Motor capacitors
include two common types, run capacitors and start capacitors.
The units of capacitance are labeled in microfarads (µF or uF or
mfd). Run capacitors  Run capacitors are mostly polypropylene
film capacitors and are designed for continuous duty, and they
are energized the entire time the motor is running. Run
capacitors are rated in a range of 1.5–100 microfarads (µF or
mfd), with voltage classifications of 370 V or 440 V. Single
phase electric motors need a capacitor to energize a second-
phase winding. If the wrong run