Pool Pump No Water Flow - Why? How To Fix It?

If you are experiencing a pool pump with no water flow, it can be hard to determine what is causing the issue.

In this article, we review some of the top causes of a pool pump experiencing low or no water flow, as well as ways you may be able to remedy this problem on your own.

Causes Of Pool Pump With No Water Flow

Pool Pump Is Leaking

A leak can easily cause a pool pump to have no water flow. Pool pump systems contain many gaskets and o-ring sealed joints, all of which must be air and water-tight in order for your filter unit to function as intended.

If air enters your filter unit through a leak, the air in your plumbing can reduce the flow of water through your pump and may even stall its operation entirely.

Air Leaks In Pool Plumbing

Similarly, air leaks in pool plumbing can cause issues for your pump and filter. If air gets entrained in the pipes connected to your pump’s housing, it can cause problems with operation.

In some cases, air will not make its way all the way to your pump but can still remain in the plumbing, which greatly reduces the amount of water that flows through these pipes.

If you stand next to the pipes while the pump is in operation, you may be able to hear the turbulence of the water against the trapped air.

Clogged Water Intake Ports

Another cause of flow issues with filters is clogged water intake ports. Commonly associated with zodiac pool pumps experiencing no flow, this problem is typically caused by skimmer baskets that have not been emptied properly.

Additionally, you should check your pool pump’s ‘check valve’.

Check valves prevent water from flowing backwards through your pump and filter unit in case of malfunctions, but sometimes they can become clogged with debris, which adds pressure drop and reduces the flow of water passing through your filter system.

Impeller Problems

The impeller in your pump unit is the piece of the machine that rotates quickly in order to produce water flow. If you have no water flow, there could be a problem with your pump’s impeller system.

Impellers can stop functioning if air or debris enters their housing, but they can also experience wear and tear over the years, especially if debris is passing through the filter occasionally and contacting the impeller.

The impeller bearings can also fail. If you have an Astral pool pump with no flow, it could be a bearings issue.

Certain models of Astral pool pump are known to need the impeller bearings replaced more frequently than other brands. If you believe this is due to a malfunction in your pump, contact your manufacturer to see if your warranty covers the problem.

Filter Needs Cleaning

Occasionally you can experience a pool pump with no water flow if your filter needs to be cleaned. High amounts of debris in any type of filter unit can cause problems with water flow.

How To Fix Pool Pump With No Water Flow

Clear Clogged Plumbing (check valve)

The first step you should take to fix your pump is to check for and remove any clogs in the pool's plumbing. Begin by emptying any skimmer baskets, then ensure that the water intake ports near these skimmer baskets are not clogged by debris that may have overflowed from the baskets.

With the pump shut off, you may use a long, flexible, metal grabber tool to reach into the drains and pipework and pull out any debris that may be present.

After checking this, you should then take a look at your pool’s check valve to ensure that no debris is lodged in the flow mechanism. Debris that you dislodge from pipes may end up here once the filter is turned back on.

Check For Leaks

Inspect your pool’s pipes for leaks. If you cannot find water escaping your pool’s plumbing, you should also make sure air bubbles are not entering your pipes.

If air is in your pipes, it is likely to accumulate near the check valve, or occasionally in the filter canister itself, which can affect your pressure readings.

Most leaks will need to be fixed by professionals. In the case where leaks are found directly on the pump unit, you may need to replace vital o-rings and other rubber gaskets that help your pump maintain ideal pressure and flow.

Inspect Pump Impeller

To inspect your impeller, keep your pump system shut off at the power source. Your pool’s pump manual should indicate the best route for you to access your impeller.

Once you have exposed part of the impeller, use a long metal grabber tool to poke around and remove any debris that may be preventing this unit from spinning.

You should be able to gently turn this unit as you clean it. If the impeller resists turning in one direction, do not force it, as many impellers can only rotate one way even when they are shut off.

Clean Your Filter Unit

To clean your filter, shut your pump off entirely at the source. If your filter uses cartridges, remove these and wash them thoroughly with clean water. If you have a filter canister, use the backwash setting to remove excess debris from the unit.