Pool Pump Capacitor

Knowing the ins and outs of your swimming pool and how it ticks can save you plenty of money in the long run but one of the reasons why a capacitor fails, besides age, is when your pool pump runs hot which happens when you don’t pay attention to simple maintenance. What is a pool pump capacitor and what does it do? 

A pool pump capacitor is similar to a battery in a car, the same reason cars need a battery to start, Pool pumps need a capacitor to start, pumps may have 1 or 2 capacitors one to start the pump, & a Run capacitor that brings the pump up to speed (3450) RPM before it switches over to AC power source.

Pool Pump Capacitors are usually the first component to go in any pool pump and they’re easy to fix. Swap them out and you’re good to go. The hard part is opening up the pump housing and getting to the actual part which are usually older pumps on older systems.


Pool Pump Capacitor


A Pool pump capacitor is a cylindrical electrical device about 3 to 4 inches long, but some models may be smaller. Some pool pump systems like the 1.5 and 2.0 hp Superpump by Hayward require two capacitors located under the motor’s housing. One capacitor helps give a little push of energy enabling the start of the pump and one helps it keep running at higher RPMs. 

Either way, a pool pump capacitor is an essential electrical component of a pool’s pumping system, and without it, a pumping system will not work properly. Most pool pumps need to get up to a speed of 3450 RPM before they can run off another energy source.

Some pool pump systems require two capacitors. One capacitor starts the pump and one helps it keep running. Either way, a pool pump capacitor is an essential component of a pool’s pumping system, and without it, a pumping system will not work properly.

Capacitor allows the pool pump to get up to speed before it switches over to using a different power source to run. The start capacitor is used to give a motor an extra electrical push to start it turning. The capacitor is located under the round cover on the back end of the pump motor.

How Do I Know if My Pump Capacitor is Bad


If you come out to your pool and find the pool pump motor off when it’s supposed to be running without a problem with external power, a timer, or a breaker then you need to test the capacitor when everything else checks out. The good news is that this electrical component is fairly inexpensive and easy to replace. Swimming Pool Pump Motors Deconstructed - In The Swim Pool Blog

  • The 1st method to know if a capacitor is dead is to use your ears-When the pool pump turns on, listen for a quiet buzz or hum. This sound indicates that the pool pump capacitor has become dead
  • The 2nd method is to know how old the component may be-Standard pool pump capacitors are only good for around 5000 starts before they go bad.
  • The third method to see if a capacitor is bad is to use your noseWhen your pool pump tries to turn on, the capacitor may be bad if you can smell a burnt electrical smell.
  • The next method involves physically testing the Capacitors inside the housing of the pump

First, make sure the power is turned off to the pump.

  • Then before you touch the wires on the capacitor, take any tool with an insulated handle and tap across two terminals on the capacitor, which will store a charge. If you touch them with bare fingers before discharging them, you might get a little zap.
  • There will be an electrical spark when you do this so make sure you are only touching the capacitor with the screwdriver.
  • After you release the capacitor’s charge, it’s safe to remove the capacitor from the larger cylinder.
  • Use a multimeter on each of the prongs to test the capacitor. Use the lowest ohm setting, and if the meter stays at 0, it’s gone bad.


How do you Determine if the Pool Pump is Not Pulling Water From Skimmer?

The most common reason for low or no flow is that the baskets are full of debris. Checking and emptying both the skimmer basket by the pool and the pump basket at the pump will free ……………………………………. Read more


Pool Pump Capacitor Replacement



Why Won’t My Pool Pump Turn On?

  • The external Power outage breaker tripped
  • Pool timer-ensure that it reset to cycle properly
  • Clogged Pump Impeller-Clean out impeller-Look for the reset button on the back motor
  • Broken pump Capacitor
  • Air locked
  • Overheated motor from being covered
  • The pump shaft is seized
  • Clogged Pump Basket  .……………………………………………………………………………. Read more



JimGalloway Author/Editor


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