Why Your Pool Pump Is Surging or Pulsing and How to Fix It

Written by Michael Dean
May 15, 2024

surging pool pump

Pool pumps shouldn’t be silent, but they should operate pretty quietly and smoothly. So, it’s a noticeable issue if your pool pump is surging or pulsing. If this is happening with your pump, you should take immediate action to sort it out. But how do you fix a surging or pulsing pool pump, and what happens if you leave it alone? I’m here to explain all this and more, so let’s get straight to it!

Main Takeaways 

  • When your pool pump is surging or pulsing, it means there is an irregular water flow.
  • A pool pump surging or pulsing can lead to issues like poor circulation and filtration, water imbalance, increased energy consumption, shortened pump lifespan, and overheating.
  • Low water levels, clogged impeller, air leaks, stuck skimmer weir, clogged filter or skimmer basket, pump motor issues, and incorrect pump size can all lead to a pool pump surge.

What Is a Pool Pump Surge?

First, what does it mean when a pool pump is surging or pulsing, and why does it occur? When a pool pump is pulsing, it typically signifies an issue within the pool’s circulation system.

Pool pumps are designed to maintain a steady and consistent flow of water. However, when a pool pump is pulsing, it means this flow is irregular. This irregular behavior can result from several factors, all of which we’ll get into below. Identifying the specific cause of this surge is essential to address the problem effectively and maintain the health of your pool.

What Happens If It Continues to Surge?

A pool pump surging or pulsing is more than an annoying noise. If a pool pump continues to surge or pulse without being addressed, it can lead to a whole range of potential problems and consequences.

  • Poor circulation and filtration: A pulsing pump won’t be able to efficiently circulate and filter the water in your pool. This will lead to poor water quality as the filtration system is unable to remove debris, contaminants, and algae effectively.
  • Water imbalance: Due to a lack of circulation, the chemicals you put in your pool will not be distributed evenly throughout the pool. This can make it much harder to maintain proper water balance and temperature.
  • Increased energy consumption: Pulsing pumps often consume more energy than pumps operating smoothly, as they are working harder to maintain proper water flow. This can lead to higher electricity bills, which is the last thing you want!
  • Shortened pump lifespan: The strain on the pump due to this issue can lead to premature wear and tear, shortening the pump’s lifespan: another significant expense you’d probably want to avoid if possible.
  • Overheating and burning out: Related to the above issue, if your pump is pulsing, your pump motor may overheat and burn out. This may eventually lead to your pump failing completely!

So now you can see that if a pool pump continues to surge or pulse, you should address the issue ASAP! But before you can fix the issue, you need to figure out the source of the problem. That way, you can appropriately address the issue at its root to ensure that your pool pump lasts as long as possible and continues to act as the heart of the entire pool system.

Causes of Pool Pump Surging or Pulsing

Pool pump surging or pulsing can severely affect the pump’s performance and efficiency. You definitely want your pump’s flow to be consistent. Pulsing pool pump flow can cause a plethora of problems for your pool. So, identifying the root cause goes a long way in sorting the problem out. Here are a few common reasons your pool pump is surging.

Low Water Levels

Cause: Pool pump surge can occur when the water level in the pool falls below a certain level. This is because, below a point, the pump will suck in air, causing surging or pulsing.

Fix: The solution is pretty simple. You need to refill the pool and maintain the water level at or a bit above the midpoint of the skimmer’s opening to ensure a consistent water supply to the pump. This is a common issue I see pool owners make that destroys pumps over time.

Clogged Impeller

Cause: The impeller spins around inside your pump and is responsible for taking water in. It is a highly mobile part of the pump and, if clogged, can seriously impede water flow, leading to irregular pumping and surging.

Fix: Turn the pump off and disconnect the power. Remove the pump housing, disassemble the pump, and gain access to the impeller. Check for blockages or obstructions around the impeller and the shaft area, and remove anything if you spot it. This is also a good time to empty the pump strainer basket. Check out my article on cleaning your pool pump impeller for more on this.

Air Leaks in Suction Lines

Cause: The suction lines in the pump create a vacuum that pulls water through the system. If there are air leaks in these lines, you can expect the pump’s ability to maintain a continuous flow of water to get disrupted, which leads to surging or pulsing.

Fix: Remove the pump housing and disassemble the pump. Inspect all suction line connections: the pump lid, seals, pipes, gaskets, and O-rings. Restore any dislodged seals or O-rings and ensure all leaks are plugged or repaired. If you find major air leaks in the suction lines, you may need to replace them entirely.

Stuck Skimmer Weir

Cause: A skimmer weir lodged in a closed position can obstruct water flow and cause the pump to pulse.

Fix: Check the skimmer weir. Is it moving freely? If it’s stuck, release it. It needs to be able to move with the flow of water. Keep the skimmer clean to prevent any further blockages. If the weir has consistent issues with moving freely, you may need to replace it.

Clogged or Dirty Filter

Cause: Check your pool filter. It’s easy for dirt and debris to build up in these areas, and as you well know, a clogged pump or filter drastically increases the load on the motor and even causes breaker trips

Fix: Rinse and backwash the pool filter and replace any filter media as needed. Regular filter maintenance means uninterrupted water flow and a healthy pump!

Clogged Skimmer Basket

Cause: If your pool’s skimmer basket is full, it can clog the plumbing, leading to your pool pump. This can make it more difficult for the pump to draw in water.

Fix: This one is easy. Simply empty the skimmer basket, and your pump’s flow should return to normal!

Pump Motor Issues

Cause: Motor problems, such as a failing capacitor or damaged windings—will lead to irregular pump operations. This can cause the pump to pulse erratically.

Fix: If you’ve narrowed down on motor issues being a potential problem, get in touch with a professional technician. You’ll need a proper diagnosis, followed by repairing or replacing the motor components as necessary. If your motor is pronounced “dead,” you’ll likely need to invest in a new pool pump or motor.

Incorrect Pump Sizing

Cause: Your pool pump should be the appropriate size for your pool. If the pump is too large or small for the pool, it can create surges and pulses as it pumps water too quickly or slowly.

Fix: Consult a pool professional to assess and suggest the right pump size as needed. The pool pump has to be correctly sized for the pool’s volume and plumbing system for maximum efficiency. Check out my pool pump size calculator for a guide on getting the right pump!

In most cases, regular pool maintenance solves most issues. Keeping the pump clean, rust-free, and free of any debris is vital for a healthy pump system and smooth operation. If you’re still encountering persistent surging problems, I recommend reaching out to a professional.

What Are the Signs of a Pool Pump Failing?

As a pool owner, it’s important to recognize when to retire your pool pump. The last thing you want is for your pool pump to fail completely and for you to have no backup until you can get to the pool store the next day or get a delivery! So, without further ado, here are some signs to look out for that signify that it’s time to get a new pool pump.

Frequent Repairs

Do you find yourself frequently repairing the pump or replacing all parts? If yes, it might be more cost-effective and sensible to buy a new pump entirely instead of continuing to repair one that is faulty.


Water leakage in or around the pump housing or below that persists despite gasket replacement, seal repairs, or O-ring replacements might indicate an underlying issue that demands pump replacement. But before you spend your hard-earned money on a new pump, make sure you are properly troubleshooting the issue.

Loud Noises

Noises such as grinding, screeching, or rattling might signify serious internal damage that is irreparable. If, after troubleshooting, the issue isn’t solved, you may need to look at replacing your pool pump.

Poor Water Flow

If there has been a significant decrease in the flow of water intake by the pump, it’s a possible indication that your pump cannot circulate water effectively. This is a possible sign that the pump needs to be retired. But, of course, first check if there’s anything else that might be affecting the water flow.


Signs of severe rust or corrosion on the pump housing or motor can majorly impede the pump’s ability to function. For instance, the impeller might be unable to turn because of extensive damage. If this is the case with your pump and the rust is simply too much for you to clean up, replace the pump.

Old Age

Finally, pumps don’t last forever. In general, a pump will last you around 8 to 12 years. So, if your pump is nearing the end of its lifespan or is past this point, a replacement is due.

Get My Free Pool Care Checklist

Download my free, printable pool maintenance checklist to help you accomplish regular pool care tasks for any type of swimming pool.

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What About a Humming Pool Pump?

Several things could be causing your pool pump to hum, such as low water flow, a blocked impeller, electrical issues, and damaged bearings. Head to my article linked above for all the potential causes and fixes for each.

Enjoy a Pulse-Free Pump!

Surging or pulsing in a pool pump can be pretty annoying, and if left unchecked, it can damage your pool system. Unless you get to the root of the problem, it’s likely to affect the quality of your swimming experience. Luckily, most fixes are simple and DIY-friendly—most of the solutions I’ve gone over above should make it easy for you to sort things out on your own.

If you’re still feeling lost, however, please reach out! I’ll happily answer any questions you have about pool pump issues.

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