Skip to Content

Pool Pump Not Circulating Water? Here’s Why (+ How to Fix)

Your pool pump needs to circulate the water, or the pool will get algae, and the motor will overheat. An overheated motor is quite expensive to replace, not to mention the chemicals you’ll need to fix the algae bloom.

You need to fix the circulation quickly to make sure these issues don’t occur.

The good news is that almost all circulation issues can be repaired without hiring a technician.

If your pool pump isn’t circulating water, here are the probable causes:

  • There’s not enough water in the pool
  • Broken or clogged impeller
  • Excess debris in the baskets
  • Incorrect valve directions
  • Clogged or damaged filter

In this post, I’ll cover the primary reasons your pool pump can’t circulate the water. I’ll also provide solutions to each of these issues, helping you get your pool back to normal.

Not Enough Water

If there’s not enough water in the pool, the water won’t flow into the inlet suction line and won’t circulate water in the pool.

Check if the water is above the pool’s skimmer basket, then make sure the gate opens to let the water flow into the inlet. A lack of water will eventually overheat the motor and trip the breaker.

How to Fix

The best way to fix this common issue is to get a solar blanket.

My preferred blanket is the Sun2Solar Solar Cover. It comes in 35 different sizes — there’s a size for you no matter your pool dimensions — and can drastically reduce evaporation.

During the hot summer months, direct sunlight removes lots of water from the pool. That’s why important to use a high-quality cover to keep the pool comfortably warm and at a good level.

The second way to fix water level issues is to repair all of the leaks in the plumbing. Try these tips:

  • Replace all of the cracked or warped O-rings.
  • Use O-ring lubricant on all of the gaskets.
  • Tighten or replace each union on the equipment pad.
  • Hire a plumber or pool service technician to fix leaky couplings and pipes.

Broken Impeller

If your pump isn’t pulling water, the impeller might be broken.

The impeller pulls the water into the pump, filter, heater, and other equipment. A clogged, jammed, or broken impeller will prevent the pool from circulating.

The pump is practically useless without a functional impeller since the motor can’t do anything.

How to Fix

You can replace your pump’s broken impeller with these steps:

  1. Turn off the pump’s power supply.
  2. Disconnect the pump’s housing assembly from the motor by removing the retaining screws.
  3. Use a screwdriver to remove the impeller (you might need a strap wrench if it’s too tight).
  4. Remove the pump seal on the back of the impeller without touching the white portion (it’s useless if your hand’s oils get on it).
  5. Place the pump seal in the new impeller with the part number provided by the manufacturer.
  6. Tighten the impeller on the motor with a screwdriver, then secure the motor to the pump’s housing assembly.

Debris-Filled Baskets

Too much debris in the pool’s baskets will slow or prevent the water from flowing. Most pools have at least two baskets:

  1. There’s a basket in the skimmer, which is the small compartment that pulls water behind a thin plastic gate.
  2. There’s a basket in the pool pump to prevent large debris from clogging the plumbing.

How to Fix

All you have to do is turn off the pump and remove the debris from the skimmer basket. Skimmer baskets get a lot of leaves, hair, sticks, and other large debris. The excess small bits flow into the pump basket.

Open the pump’s lid, remove the basket, and dump everything out of it. Anything that passes through the pump’s basket will go to the filter, so that needs to be emptied eventually (I’ll dive into the step-by-step process later in the post).

These baskets should be emptied at least once to twice per week. Depending on how much debris gets into the pool, some baskets may need to be emptied more often.

If trees and bushes surround your pool or your pets swim in the water, you’ll likely have to empty these two baskets daily.

Incorrect Valve Direction

If your pool pump has valves, they have to face the correct direction. If you have a spa, some valves push water into the spa, so your pool might not circulate if they’re facing the wrong way.

Check the valves to ensure they’re facing whichever way pulls water from the pool, then check the return valves to ensure they push the water into the pool.

How to Fix

Changing the valve’s direction almost always fixes this issue.

Look for a valve with a lever in front of the pump — this is known as the suction valve.

The suction valve decides where the pump pulls the water from. Make sure the valve is pointed toward the inlet pipe coming from the pool.

Next, look for a valve after all of the equipment right before the water gets back to the pool. This valve is known as the return valve.

Ensure the return valve faces the line going to the pool, not the spa. I suggest labeling the valves so you know which way they need to be.

Clogged Filter

A clogged pool filter will drastically reduce the water’s circulation, so checking for excess debris is important.

Your pool filter’s PSI shouldn’t exceed 25 in most cases. If it gets too high, the water won’t circulate, and the pump’s motor will overheat.

Clogged filters can also cause leaky cartridges, unions, O-rings, plumbing, and more.

How to Fix

Unclog your pool’s filter with this process:

  1. Turn off the pool pump.
  2. Remove the retaining bracket from the filter, then set the top portion (or lid) aside.
  3. Pull the cartridges out of the filter and spray them off to remove the excess debris.
  4. Place the cartridges into the filter, then replace any of them if they have torn pleats or bands.
  5. Seal the filter’s lid onto the bottom portion that holds the cartridges, then prime the pump.

Check out Swim University’s video tutorial to learn how to clean a DE or sand filter:

Additional Pool Pump Troubleshooting Resources

If you have any other issues with your pool pump, check out our other pool pump troubleshooting articles: