A common reason for pumps not starting is failure of the start capacitor. There can be two types of capacitors in a pump - a start capacitor and/or a run capacitor.
Not all motors have run capacitors. The newer VS pumps do not have a start capacitor either.
The start capacitor is often under the small bump at the top of the motor. Or it can be inside the motor.
Some capacitors have a bleed resistor connecting the two prongs. If your capacitor has a bleed resistor it should be moved to the new capacitor.[1]
Be careful when handling a capacitor. It can hold a voltage charge for a long time and you can be shocked by it. To drain all the power out of a capacitor you can touch both prongs together with the shaft of an insulated screwdriver. You may get a spark or pop from the current outflow.
The voltage rating should be at least √2 x the intended voltage. Assuming a maximum voltage of 250 volts, the capacitor minimum rating should be 354 volts. So, 370 volts should be fine. 440V is a better quality capacitor and will last longer, especially under high temperature conditions, but the 370 volt should be fine.[2]
It has been reported that many Ace Hardware Stores carry start capacitors if you need something right now.[3]
How To Select the Right Capacitor For Your Pool Pump Motor
How To Replace a Pool Pump Capacitor
Tips
- If it's not the capacitor, it's probably a bad centrifugal switch.
