Robot Pool Cleaner Brushes or Tracks Not Scrubbing? Fixes

On this page4 sections

1. Why this happens
2. Fix it in order
3. Maintenance that keeps grip
4. When it is the robot, not your pool

What is going wrong

• 1Glazed tracksThe surfaces that drive the machine are the ones that scrub, so a worn set costs grip and cleaning at the same time.
• 2Load behind itA machine already fighting a loaded filter presses less hard on the surface it is meant to be working.

Why this happens

Scrubbing is friction. A cleaner works because textured brushes and tracks bite into the pool surface and lift film as the robot moves. Over seasons of sun, chlorine, and heat, foam and rubber brushes flatten and harden, losing the edge that does the work. PVA brushes rely on staying damp and swollen, and they stiffen and shrink if they dry out between uses. Tracks and tires glaze to a smooth polish as the tread wears, so they slide across the floor instead of gripping it. On algae the effect is worse, because a slick film gives a worn brush nothing to catch, and the robot glides over the growth rather than removing it.

Fix it in order

Work through these from the top. Start with the parts that wear first.

1. 1

   Brush profile

   Inspect the brushes for flattening and hardening.

   Compare against a new brush profile in the manual. Flattened, stiff, or cracked brushes have lost their grip and should be replaced.

2. 2

   Kept wet

   Keep PVA brushes damp.

   If your model uses PVA, store it so the brushes stay wet. A dried, hardened PVA brush will not conform to the surface, and soaking may not fully restore it.

3. 3

   Glazed tread

   Check the tracks or tires for glazing.

   Look for a smooth, shiny tread. Glazed tracks slip rather than drive, and worn ones need replacing.

4. 4

   Axle cleared

   Clear the brushes and drive path of debris.

   Hair, fibers, and grit wrapped around a brush or axle stop it from turning and rob the scrub. Remove anything wound in.

5. 5

   Algae brushed

   Brush and shock heavy algae before running.

   A worn or even a good brush slips on slick algae. Knock the film back manually and correct chemistry so the robot has something to grip.

6. 6

   Renewed as a set

   Replace worn contact parts as a set.

   Brushes and tracks wear together. Renewing them restores the friction the cleaner depends on.

Maintenance that keeps grip

• Sun and chlorine aging. These harden foam and rubber over time. Plan on brushes as consumables.
• PVA moisture. Damp is the working state for PVA. Drying out is a common cause of lost scrub.
• Track glazing. A polished tread slips. Texture is what drives the robot forward.
• Algae load. Slick growth defeats a worn brush. Manual knockdown plus chemistry comes first.