Troubleshooting Tips for Automatic Pool Cleaners

Today's pool professional has learned to incorporate the automatic pool cleaner into their service routine, and retailers are frequently selling the units to their pool owner customers. With so many automatic pool cleaners in the market, pool professionals must now be versed in how to troubleshoot common problems and user mistakes when using the product. Like any robotic product, there are some common user errors and sometimes-faulty parts that can cause an automatic pool cleaner to malfunction. This article provides troubleshooting solutions for pool professionals and aquatic facility managers when automatic pool cleaners aren't working properly.

The automatic pool cleaner 'flips' upside-down or does 'wheelies.'


The water level in a pool is one of the most common causes for automatic pool cleaners to flip over. When the water level on the skimmer is too high, the water line is too close to the coping. So when the automatic cleaner start to climb up the pool wall, it hits the coping and flips on to its back. This is actually very detrimental to the motor(s) on the cleaner because the motor is no longer in the water—but exposed above the water. The motor of the robotic cleaner is cooled by the water, so having it run out of water allows it to get hot fast and fail. Depending on the temperature of the day, the motor could fail as quickly as within one hour. (If it's really hot, say 90 degrees, it only takes a matter of minutes.)

When an aquatic facility staff member first uses an automatic cleaner they often forget to remove all of the air in the unit before starting the machine. Not only can this cause flips and wheelies, but it also keeps the cleaner from performing correctly. This happens the first time they use the unit. If the unit still has air, it tends to "float" sometimes just an inch above the floor—so it looks like it might be working—as it moves forward—but isn't touching the floor to actually clean. It can take up to 30 minutes to remove all of the air. One must hold the unit under the water and shake it from left to right and up and down—watching the water bubbles come out. Then one must carefully watch that the unit actually hits the shallow end floor.

Remember also that there is the possibility that the pump motor is weak or turning too slowly, so the only solution might be to replace the motor.

The robot does not lay flat on the pool.

Most likely the PVA (poly vinyl alcohol) brushes have not absorbed the water. This is a very common call and easy to fix. Simply let the automatic pool cleaner sit in the pool for at least 30 minutes or until brushes are soft. Once the brushes are soft, the unit will lay flat on the pool floor.

The robotic cleaners will not climb walls.

Sometimes the solution to this problem can be as simple as ensuring the pool water isn't too cold. In order for the robotic cleaner to operate correctly, the water needs to be at least 60 degrees Fahrenheit. Water can also get into the handle that may cause the unit to lift brushes from the wall and will break the suction making the unit fall from the wall. Users should try to place the handle at an angle to remove the water so unit can climb the wall. Or it is possible that the handle needs to be replaced. If the temperature is above 60 degrees Fahrenheit and the handle doesn't have water in it, then there is also the possibility that the pump motor or propeller is defective. If this is the case, you will likely see an early shutdown of the unit and the pump motor will need to be replaced.

The robotic cleaner falls backward off the pool wall.

The most likely cause is water in the handle of the unit. If the handle is cracked, water will leak in and disrupt normal operation. To determine if there is water in the handle, simply remove the unit from the pool and place on the pool deck and move the handle back and forth and listen for sloshing water.

The robotic cleaner will not move or moves in short, jerky motions.

Though it's obvious, be sure that the power supply is connected properly to the power outlet. If the unit moves in short, jerky motions, the unit could have a deteriorated drive belt that can be simply replaced to solve the problem. Debris could also be stuck in the drive pulleys, so it's important to inspect for and remove any debris then retry the unit. If the pulley teeth are filled or missing, replacing the pulley is another simple solution. It's also important to check the wear and tear of brushes and drive tracks, which can also become worn with use and need to be replaced. Lastly, check to see if the bottom lid assembly is secured as it could be dragging on the pool floor and causing irregular movements. Simply turn over the unit and secure the lid. Worse case, the unit may need new lock tabs.

What tips can you offer to ensure the full life of the cleaner motor? What are some of the common causes of motors that burn out prematurely?

Overheating of the motor is the number one problem. This can be caused by several factors.

Pools that have beach entry should use an automatic cleaner with a pump motor that uses a "beach boy" (or similar) feature—a sensor that is used to detect zero-depth water level and prevents the cleaner from exiting the water. Without this type of feature, an automatic pool cleaner can simply travel out of the pool and down the deck or down the street. The motor is sure to fail, as motors require the water to cool the electrical motor. Overheating causes failure. Some units feature "air sensors," which tend to fail because they use additional wiring that will corrode from moisture exposure or the mechanical parts get clogged and stuck. Try to choose a cleaner with a drive motor that senses voltage draw from the pump; when the voltage draw drops, the drive motor assumes the machine is out of the water and reverses its direction. This way there is no way for the motor to get out of the water, overheat and fail.

Using a cleaner that uses an Aqua Smart system (or similar) also minimizes the wear and tear on the motor, its gears, belts, tracks etc., simply because the unit finishes each pool cleaning faster—so it's not on unnecessarily or as long.

Flipped cleaners where the motor is exposed and not being cooled by water, is one of the number one causes of motor failure.

Most automatic cleaners need to be serviced after every season, but units with an Aqua Smart system (or similar) only need tune-ups every two years. Tune-ups are important to ensuring a longer motor life.

Some cleaners seem to take forever and clean the same area over and over. Is there a way to avoid this?


Look for automatic cleaners that have systems that automatically change the cleaning direction using a smart mathematical algorithm to systematically cover every centimeter of the pool—eliminating the additional hours required by other robotic cleaners that use conventional, random patterns.

Place the machine in the center of the shallow end—at the back wall—facing the deep end. The machine measures the distance from end to end and left to right and "chooses" the most efficient pattern in which to clean the pool. Using a microprocessor, it measures the pool as it travels until it hits the deep end wall and from left to right. It re-measures every time the machine is dropped into a pool.

Many people make the mistake of dropping the machine anywhere in the shallow end (or similar as indicated in the installation/start up instructions). If the machine doesn't start in the correct location, it cannot gauge the size of the pool or the best cleaning pattern. This causes longer cleaning times or not covering the entire pool area.

Are there any special tips/ features to look for in an automatic pool cleaner?

In the case of commercial pools, the cleaning of the walls is generally done manually and the automatic cleaner is added simply to clean the bottom of the pool. Look for an automatic cleaner that can be changed from a "floor/wall" to a "floor only" mode at the touch of a button.

Sometimes commercial pools are so dirty that they require more than one full cleaning. A nice option to look for is a "time delay" option in which you can set the cleaner to start again 3 to 5 hours after it completes the first cleaning. This allows any dirt that has been lifted to settle back down to the floor bottom to be picked up on the second round.

A service light is another key feature for commercial pools—this shows the operator when the unit needs to be serviced to ensure the machine operates correctly and lasts up to its full potential.

What about spot cleaning—sometimes we just need the shallow end to be quickly cleaned—are there automatic cleaners that can help with this?

Look for an automatic pool cleaner with an infrared obstacle detection system and a remote control device ideal for quick spot cleaning. It operates independently of the filter system and has a sensor for beach entry pools and ramps. This can be helpful for spot cleaning.

What are some of the most common "technical" problems and solutions that users and pool professionals will likely find themselves troubleshooting daily or weekly?

This time of year, the calls come from parts of the country that are warm enough not to close the pool for the winter—but their pools are not being used by swimmers—so the water is cold! An automatic pool cleaner won't work in really cold water. Anything under 60 degrees will keep a cleaner from operating correctly.

If any of these problems turn out to be issues that fall under warranty or require repair, be sure to check with the manufacturer of the product as they likely will have a Certified Service Center where the units are sent in for repair.

In the end, automatic robotic pool cleaners are here to stay and benefit our industry. Integrating robotic cleaners into your service offering so you can spend less time cleaning the pool and more time doing profitable service repair work, or simply cleaning more pools per hour, the automatic pool cleaner is a boon to the service business.



Guy Erlich is the founder and president of Water Tech Corp., a manufacturer of swimming pool and hot tub cleaners in East Brunswick, N.J. For more information, visit