Why Does My Pool Pump Capacitor Keep Blowing? Easy Repairs

Pool pump capacitors are responsible for delivering the initial jolt of energy required to power the pump. If the capacitor is damaged or doesn’t work, your pool filtration system won’t work. Additionally, if you’re replacing the capacitor more than once every 5 to 10 years, there’s a problem.

Your pool pump capacitor keeps blowing because it’s not compatible with the motor, the motor keeps overheating, or the capacitor gets wet. Other potential explanations include the capacitor getting overloaded by the circuit breaker or the pump running too often.

In this article, I’m going to explain why you keep having to replace your pool pump’s capacitor, how long the capacitor should last, and whether or not the pump will work without the capacitor.

Why Do I Keep Having to Replace My Pool Pump Capacitor?

If your pool pump capacitor keeps going bad, there’s a high chance that another pump component is damaged or failing. For example, if the motor overheats because it’s not rated for your pool’s capacity, it could ruin the capacitor every couple of years.

Here’s a list of causes and fixes for a pool pump capacitor that keeps blowing:

1. The capacitor isn’t the right part number for the pump motor. I can’t tell you how many times I’ve seen people use the wrong capacitor for their pool pump. Always use the capacitor’s part number that’s provided by the manufacturer’s part diagram.
2. The pump motor keeps overheating because it’s working too hard. This often happens when your pool pump is higher than the pool. The pool has to pull water uphill, causing it to work overtime. Keep your pool pump within 3 feet of elevation from the water level, then make sure there’s no air in the filtration system.
3. A soaked capacitor will lose its power every time. Your pool pump shouldn’t get wet if the seals are damaged. Moisture can get into the capacitor, frying it. Replace the capacitor seal and replace any of the screws if they’re stripped. You can also put a motor cover over the pump.
4. Incorrect electrical wiring can ruin the pump capacitor. Tighten each of the wires going to and from the pool pump. Turn off the circuit breaker, remove the capacitor cover, and make sure the capacitor is secured under the cover. Also, choose a circuit breaker that has enough volts and amps for your pool pump (use a dedicated breaker for your equipment pad).
5. Running the pump for too long or too often can wear down its capacitor. I always recommend running a pool pump for one hour per 10 degrees Fahrenheit outside. If it’s 60 degrees outside, run your pool pump for 6 hours. This becomes much more manageable if you have a variable-speed pump.

How Long Should a Pool Pump Capacitor Last?

A pool pump capacitor should last up to 10 years, though they usually last between 5 to 7 years. Some pump motor capacitors are rated to last well over a decade. Check your pump manufacturer’s warranty agreement to know if you can have the capacitor replaced by the company.

So, how do you know if your pool pump capacitor is failing?

• If the pump can’t maintain its pressure and there aren’t any leaks, the capacitor might be malfunctioning. This is because the capacitor can’t provide enough power to the motor, which means the motor can’t rotate the impeller. When the impeller doesn’t move, the pool water can’t move through the plumbing.
• Most faulty swimming pool pump capacitors hum and buzz. Humming is the most common symptom I’ve noticed that comes with a failing pool pump capacitor. The capacitor tries to supply power, so it buzzes until it overheats.
• The majority of pool pump capacitors are based on power cycles rather than years. According to Flower Mound Pool Service claims most pool pump capacitors last 5,000 cycles before they need to be replaced. In other words, the pump can turn on 5,000 times until the capacitor has to be replaced.

I suggest using the AstroAI Multimeter 2000 to test your pool pump capacitor. Set it to 1,000 Ohms, then place a probe on both capacitor terminals. If it reads 0, replace the capacitor. This multimeter also tests volts, amps, and more.

Can a Pool Pump Run Without a Capacitor?

A pool pump can’t run without a capacitor because it needs an initial power supply. When the capacitor stops working, it’ll hum and the pump won’t pull water into the pump housing or through the filter. Turn off the power immediately, then replace the capacitor.

The good news is that you can rebuild a pool pump by replacing the motor, capacitor, and other parts. Sometimes, replacing other pool pump parts can help the capacitor last a lot longer. For instance, a malfunctioning motor with rusted bearings will overheat and damage a new capacitor.

Another option is to test the capacitor if you think it’s on its way out. In the Swim suggests using an Ohm meter to check the capacitor before replacing it. Not only will this prevent electrical shock, but it’ll also make sure you don’t replace a capacitor that still works.

Keep this in mind before running a pool pump with a faulty capacitor:

• Your pool pump will likely overheat since it keeps trying to complete an electrical circuit.
• The capacitor will hum and get very hot, potentially causing fire risks.
• There’s a good chance that a faulty pump motor will trip the connected breaker, preventing any of the equipment from working.
• The pump won’t be able to circulate the water throughout the pool, but it’ll still use a lot of electricity.

Ultimately, a capacitor is a crucial and necessary part of a swimming pool pump. Without it, your pump won’t work properly.

If your pool pump’s capacitor keeps blowing, it’s time to look at all other parts of your pool pump. The impeller, plumbing, motor, and air in the system can damage the pump capacitor long before you should have to replace it. Pool pumps are complex systems, but everything connects and affects each other.