Automatic Pool Cleaner Troubleshooting Guide

Pool Cleaner Types, Suction, Pressure, Robotic
Automatic pool cleaners
are an integral part of pool maintenance; disaster strikes and time comes to a standstill if your pool cleaner stops working. Symptoms include jitters, sweaty palms, and trembling hands – accompanied by a feeling of injustice and loss. But really, help is out there and by following just a few simple steps, you can actually troubleshoot your automatic pool cleaner and get it running again.

Though pool cleaners are available in a wide variety of various types, there are some basic guidelines you can follow to troubleshoot your pool cleaner if it decides to call it quits or becomes sluggish. First of all, let’s walk you through some of the most common reasons why a pool cleaner may quit working and then discuss how to fix those problems yourself- absolutely without the need to call the National Guard.

There are 3 main types of pool cleaners, Suction, Pressure and Robotic. Suction cleaners connect into a suction line like the skimmer, or a dedicated cleaner line that is sucking water into the filter pump. Pressure cleaners, operate on the pressure side of the filter pump – that is, they are powered by water being pushed to the cleaner, usually by a separate booster pump. Robotic cleaners are independent of the filter pump, they operate under their own power and don’t rely on the suction or pressure of your filter pump.

For this blog post, I’ll cover all 3 automatic pool cleaner types.

suction pool cleaners

Suction Pool Cleaner Does Not Move

Suction pool cleaners are powered by your pump water flow when the pump is operating; they cover the whole pool in a random pattern – only while the pool circulation system is on.

For a suction pool cleaner that is not working at all, the first step is to check the cleaner hose to make sure that it is firmly attached to the suction line in the skimmer or to the dedicated cleaner line, if your pool is equipped with one.

Second step is to check the hose sections to make sure that there are no air leaks, either where the hose sections join together, or from splits or holes in the hose.

You may need to close down or restrict other suction lines, such as the main drain or another skimmer, to increase the suction on the line that the cleaner is connected into.

Suction Pool Cleaner is Slow

Usually the main reason for this kind of dysfunction is a congested pool filter or a clog at the intake hole at the bottom of your pool cleaner. To clean the intake hole, just flip the cleaner over underwater and look down into the intake hole.

You will also want to make sure that there are no obstructions in the hose, and that all hose connections are tight and secure.

Next step is to clean your skimmer basket, pump basket, and pool filter. If there are leaves or rocks trapped in there, it will reduce your pumps water flow which in turn will slow down a suction pool cleaner.

Suction Cleaner is Too Fast

As mentioned above, suction pool cleaners work based on your pool pump water flow. If you have an especially powerful pool pump or your water flow is exceptionally fast, your pool cleaners may move faster than usual. This can cause your cleaner to skip over some debris, as it “flies” around the pool.

Most suction cleaners have a device in the skimmer that will allow you to control the flow, or if you have other incoming suction lines, such as a main drain or secondary skimmer. Opening these lines more fully will reduce the flow from the line that the cleaner is connected to.

Suction Cleaner Does Not Cover Entire Pool

Seems like a big issue but the solution may be as simple as checking the hose length. In order for the pool cleaner to be able to reach all areas of your pool, the hose should be long enough to reach from the skimmer or dedicated suction line to the furthest point in the pool with 3 feet to spare. If the suction hose is not long enough, consider adding extra lengths of hose.

Adjustments to the direction of the return jets in your pool can affect cleaner coverage. Your returning water may be pushing your cleaner away from certain areas.

If the hose length or return flow is not the problem, consult your owner’s manual for slight adjustments to the hose or cleaner which will create a different cleaning pattern.

Air Bubbles Enter Pool at Return Line

This may be caused by air leaks in the hose or the connections. If the vacuum connections are not fitted together tightly or the hose is punctured, air will leak into the system, causing bubbles to appear at the return wall fitting.

Check the hose and vacuum connections for any air leaks; the vacuum connections can be tightened and secured with o-rings and hose leaks can be easily fixed with silicone or rubber cement (which looks better than duct tape!).

Suction Cleaner Gets Stuck on Steps/Ladders

Most suction cleaners have a device that snaps onto the throat of the cleaner, to keep it from getting stuck on steps. This is an aftermarket item for some cleaners.

If your cleaner is getting stuck on/under your pool ladder, you may consider installing a Ladder Guard Kit and if it sticks on a raised main drain cover, look at the UniCover, which creates a smooth transition from floor to drain.

Visit our pool cleaner parts department for any spares you need.

Pressure Pool Cleaner Does Not Move

Pressure pool cleaners need to have about 30 psi to operate (17 psi for low-pressure cleaners like the Polaris 360 or Letro Legend II). Check that the booster pump is operating, and – the filter pump should also be running at the same time.

Pressure cleaners have an inline strainer (some have two) that needs to be cleaned periodically. This may be located in the wall fitting connection, or in the feed hose.

Rocks or sand can become lodged in the wheels or a pressure cleaner, preventing movement. Likewise, tiny grains of sand or plaster can make their way around inline strainers (especially if you’ve lost yours!) and can clog up small orifices inside the cleaner.

Pressure cleaners may be shaft driven, belt driven or chain driven. Either one of these power trains can have problems. Generally speaking, these are working well if you turn one wheel and the other wheels turn at the same time and speed.

Pressure Pool Cleaner is Slow

Check the inline strainer(s) for debris that is slowing down the water flow to the cleaner. Also check the hose, to make sure that pressure is not being lost somewhere along the line. Slight water loss around the hose swivels is normal.

Loose wheels or loose drive belts can cause your cleaner to behave sluggishly. Worn tires will reduce speed and wall climbing ability. Check your owner’s manual for specific adjustments for your particular pressure pool cleaner.

Pressure Cleaner Does Not Cover Entire Pool

For this problem, all you need to do is adjust the thrust jet, located on the back center, where the water sprays out. 11 o’clock is the default setting, but placing it at 1 o’clock will give the cleaner an opposite cleaning pattern.

The feed hose of course must be long enough to reach the furthest point from the wall connection, plus 3 feet. And, make sure that the feed hose is floating – old style hose floats can become water logged and not keep the hose up on the surface.

Pressure Cleaner Gets Stuck on Steps/Ladders

If your pressure cleaner gets stuck on the stairs – try to adjust the thrust jet to create a new cleaning pattern. If you cleaner gets wrapped around a handrail or stuck behind a ladder, install ladder guards to block the path around these rails.

Pressure Cleaner Feed Hose Becomes Tangled

Measure the hose to ensure that it is adjusted to the proper length for the pool size – too much hose will cause tangling. You also need to make sure that the feed hose is floating. Waterlogged hose floats should be replaced. The hose swivels should rotate freely. One other possibility is that not all wheels are being powered. Rotate one of the wheels when the cleaner is in OFF mode and make sure that all wheels turn together.

Too much power to a pressure cleaner can cause it to fly around the pool and tangle itself. Bleed off excess pressure at the wall fitting. Finally, if the thrust jet is in a 9 or 3 o’clock position, this will create a circular pattern, which may cause tangling. Visit our pool cleaner parts department for all of these parts mentioned.

Robotic Pool Cleaner Does Not Move

Robotic pool cleaners are electric, and don’t rely on your pump’s suction or pressure to move around the pool. The floating power cord for your robotic pool cleaner should be firmly plugged into the power supply transformer, which is plugged into an outlet. The power supply should have an indicator light – indicating that power is being received.

If power is being received to the power supply, but the cleaner is not moving, we need to trace the problem towards the cleaner. The problem lies, where the power dies. Many times, the power cord itself can have a short, where the wires have broken, inside the rubber casing. This usually occurs at a point near the cleaner, where the stress on the cord is the greatest. If you have a dog that goes after the robot, look for bite marks in the cord!

If the cord is intact, you can test the resistance of the wire with a test meter (set on Ohms) to ensure that the cord wires are not an issue. At this point, you will want to check the drive motor itself, to make sure connections are tight, and using your test meter, check that the power is reaching the motor. If it is, and the motor is not responding to the power, this may be signaling the need for a new drive motor.

Robotic Pool Cleaner is Slow

This is usually a problem of loose drive tracks, loose drive belts or missing small parts that keep tension on the belts and tracks. You may notice that it moves, but doesn’t climb the walls any more. This could indicate worn drive tracks or wheel tube brushes.

Robotic Cleaner Gets Stuck

If your floor surface is not so smooth, you may find the cleaner getting stuck on high spots. Some newer models have adjustments that will raise the cleaner slightly, but this may compromise it’s vacuuming ability. Robot cleaners can also get stuck behind ladders and handrails, and like our other pool cleaners above, you can solve this problem with a product called a Ladder Guard.

Mayday Mayday Mayday

If everything has failed and your pool cleaner is being stubborn and is refusing to cooperate, it may be time to call one of our pool specialists/advisers who can assist with you further with troubleshooting or repair. Of course, our specialists can also help you select a new pool cleaner if you’d rather just start over.

But that’s usually not the case – most of the time, your pool cleaner just needs a few tweaks here or there, or some pool cleaner parts, and it’s off and running again – without the need for a visit from the National Guard!

Happy Trouble-Shooting!


Ayesha Aslam
InTheSwim Staff Blogger



Automatic Pool Cleaner Troubleshooting Guide — 10 Comments

  1. I have an aqua jet electric that worked great for 5 years. Now when I put it in, it starts fine. Then after about 5 or 10 minutes it just stops. The poet supply is still lit and clicking to change directions, but the aqua jet won’t move. This starting the r d of last season and behaved the same first time in the water this year. I love my swisher but none around d here works on them. Help!

    • Hi Tammy, from the Aquabot AquaJet Owner’s Manual: “Take a garden hose with high pressure, spray into the Valve Housing at each Valve Port opening. This should free the Jet Valve System of any debris. If this does not solve the problem, there is most likely debris wrapped around the Propeller beneath the Jet Valve or between the Valve Flap and the Valve Housing wall.”

      Now since it works and then stops working, i don’t think anything is clogged or restricted. Inspect the power cord very carefully, moving it through your hands to see if you moving the cord starts the cleaner again. The floating cords can break inside the casing, without any external damage, especially near the cleaner, where it enters the cleaner. Cords can be shortened and reattached, or you can buy a replacement cord if that is the issue. Power can also be tested at the motor, with the cover off, after it stops moving, to determine if it’s the power cord or the motor that is failing.

    • The reason that a pressure cleaner like a Polaris or Kreepy (Letro) Legend might float is usually that air is trapped inside of the unit. Holding it underwater, flip it over and shake a bit to let the air escape. They also may kind of ‘float’ around the floor, not contacting all surfaces, when the booster pump water pressure is low, usually from a clogged inline strainer, or sometimes something jammed in between the wheels, or an internal blockage that keeps the wheels from moving.

    • Hi Rosemary, I read thru the manual – and it did not address air suction between hose sections, but I would first make sure all connections are tight (I assume they are threaded, but maybe they are twist lock). If threaded, you could use Teflon tape or other thread sealant on the male threads, to help seal it up. If they are gasketed, with an o-ring, Teflon lubricant can be used (or Silicone, actually better) to help seal up the oring or gasket.

      Now, i should say that if you are using a pump and filter system that is too large for the cleaner (it is meant to work with the 1500gph to 3500 gph Intex filter systems, then that could be the problem. In such a case, you could modify the wall fitting, by drilling holes in it, to relieve some of the vacuum suction on the hose sections. To clarify, the first hose section that connects to the wall fitting – If your pump is too large, you could drill small holes in the solid part of the fitting, to pull water in at that point, to create a bypass or alternate suction intake, however be careful that this does not create a suction entrapment hazard, drilling many small holes all around the fitting, is probably safer than one large hole in the side.

  2. the push rod that goes to the turning cog keeps breaking on one side when it turns after hitting the actuater bumper turn bar.

    • Hi TIm, are you talking about an Aquavac robotic cleaner? The sensor bar slide that connects to the push bar and the adjusting arm? Adjustments to the adjustment arm (the one with the spring on it) can provide a bit more room or play between the parts. Changing cleaner direction may also help, as it could be one particular spot on the pool that is at the wrong angle, causing the damage.

  3. Hello Ayesha,

    I’m a pool cleaner. I have an account where the Shark suction cleaner used to work great, now it’s slow and less efficient. It’s vinyl pool. Backwashing helps, but never as good as it used to go all the time. We bought a new shark. I replaced the pump motor and the impeller, which was severely clogged with grass. I also replaced the pump basket which was cracked. Pool gets lots of grass, but it should be working great with all these adjustments. Played with the skimmer valve, that’s not it. Sand looks normal in the filter. Anything I’m missing?
    Thank you,
    Richard Schnittger
    Pisces Pool Service Oahu

    • Hi Richard, any chance that a line (pipe) could be clogged or restricted (partially collapsed if flex pipe) or something reducing the flow volume from the skimmer? Is there a separate main drain valve or second skimmer that can be throttled? When a cleaner is connected, this created some vacuum pressure, which makes it easier for air leaks to occur around the pump, and the pump would prefer to draw from other lines that are less work to draw from. Another slim possibility is a solar return valve that is open, which is a line connecting the return line to the main drain line, on some pools back in the day.

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