Today’s automatic pool cleaners are longer-lasting than ever. Still, no system is immune to parts wear or flow problems.

Though in-floor cleaning systems and robotic cleaners continue to gain market share, most common cleaners still work off the pump as pressure- and suction-side units.

Nonetheless, it can’t hurt to address some troubleshooting basics for all four. Here, service pros tell what to look for when cleaners act up.

Pressure- and suction-side cleaners
Pressure- and suction-side cleaners can’t function without working hydraulics. Nor will they run properly without a priming pump, a clean filter and unobstructed flow.

Before touching the cleaner, inspect the pressure gauges and pump or booster pump for potential problems such as parts wear (fairly common, though it could be in a few different areas) or worn hoses.

“On the pressure-side, you may see something where the pump has run dry,” says Don Pollard, owner of The Pool Pro in Glendora, Calif.

In fact, nearly every cleaner is plagued by worn hoses, and one of the first suspects should be the connecting hose.

The hose also can be a frequent site of obstructions. Check the couplings first, as these are the most likely places for debris to lodge.

Other parts replacement may be a matter of make. On some pressure-side cleaners, look for worn belts that could prevent the cleaner from running properly. Other models contain a flotation device that can crack or, when water is allowed in, may wind up lopsided.

On cleaners with rubber diaphragms, debris tends to get caught within the actual cleaner; and sharp objects can puncture the rubber.

“Sometimes, debris will actually tear the diaphragm as it goes through, so you [have to] look for perforations also,” Pollard says.

When re-assembling the unit, make sure you don’t twist the bearings or gaskets too tightly.
“A lot of people don’t recognize if you torque everything down, it won’t run right – the turbine won’t spin,” says Alan Stoner, owner of Arizona Pool Remodeling and Service in Glendale, Ariz.

To avoid stripping threads and cracking parts, stop tightening when you feel the first bit of tension.

In-floor cleaning systems
Pop-up cleaners, like any other system, are subject to flow problems and worn-down parts. Thankfully for pool techs, most repairs can be done above water.

As with other cleaners, filter gauges should be the first stop on any troubleshooting mission. Each system is different in terms of acceptable psi reading, but a plugged filter should always be checked prior to investigating the actual pop-up water valve assembly.

On most in-floor systems, the valve assembly box is located near the equipment pad. The assembly’s screen should be cleaned regularly to allow adequate flow through the system.
However, it may be the gears themselves that are restricting flow.

“There are different types, but basically they won’t rotate around, or some [designs] won’t let water flow through them,” Stoner says.

Blockages often are the result of broken gears, and usually can be solved with a simple parts replacement.

If the filter, screen and valve assembly show no signs of malfunction, the problem may be with the actual pop-up heads.

“They don’t typically go bad, but when they do, sometimes they can be a real pain to get out,” Pollard says. “Without draining the pool, there’s almost no way to do it.”

Though there are tools to remove the pop-up heads without entering the water, it’s difficult to get the necessary leverage from the deck, he says.

Neglected corners of the pool floor aren’t necessarily the result of faulty equipment or restricted flow. Bad design can just as easily cause dead spots, particularly around steps.
“Once it’s in the pool and it doesn’t sweep it properly, there’s nothing you can do,” says Ed Penfield, owner of Aqua Island Technologies in Everson, Wash.

Ideally, pop-up heads should be placed no more than 8 feet apart.

Robotic cleaners
Troubleshooting robotic cleaners can be done independently of the pool’s hydraulic system, mainly because these cleaners are powered by AC voltage. Therefore, if the cleaner stops working, the first check should be the power.

Most units have an indicator light. If the light is off, check the transformer; you may have to replace the fuse.

If the unit still doesn’t move, check the drive belts. Like any moving part, these belts are subject to deterioration. For example, over time drive belts can begin to skip and may refuse to move with the pulley or wheel tubes.

“I have [my commercial clients] buy two sets of treads, because as soon as we hit the spring and people really start using the pool, tracks are worn off after three months,” says John Balistreri, owner of Balistreri Pool Service in Petaluma, Calif.

Before replacing a belt, make sure the wheel tubes are straight. If they aren’t, the drive belts won’t stay on regardless of what condition they’re in.

If the cleaner is getting power but isn’t cleaning the pool effectively, the problem likely lies with the pump motor. Try bringing the unit to the surface. If water doesn’t geyser up, the pump probably is malfunctioning.

Take the cleaner out of the pool and unplug it. After removing the vent cap, check the impeller for any debris or obstructions.

Spin the impeller by hand to ensure it turns without difficulty. If it doesn’t, plug the unit in and watch the rotation. If it doesn’t spin, the pump motor is likely shorted. You’ll probably have to replace the motor.

You may also need a new motor if the unit has trouble climbing walls — a problem often attributed to the motor failing to create enough suction.

One final note of caution: Never remove the cleaner from the water by the power cord. It’s a surefire way to get an electric shock.