Search guides

Fix a robot pool cleaner that will not clean

We'll confirm the symptom, rule out power and water level, then check the filter, impeller, and drive—or tell you when to call a pro.

Troubleshooting · Home appliances
15–45 min
What you'll need
  • Hose (for rinsing filter)
  • Owner's manual (for filter access, impeller location)
  • Replacement filter bag or tracks (if worn)
Diagnostic graph validation issues: Terminal node n_tracks must have null branches
Step 1 of 9

Quick triage — pick your path

Get started

Choose the option that matches what you see. You can jump straight to that section.

Show full guide

Steps

Goal: Confirm the symptom, rule out power and water level, then isolate the cause—filter, impeller, or drive.

  • Place the robot in the pool and start a cycle. Check if it runs and picks up debris.
  • Good: The robot runs but leaves debris—filter or impeller may be blocked. Proceed to Check power and cable.
  • Bad: The robot does not run—power or motor fault. Proceed to Check power and cable.
  • Worse: The robot hums but does not move or pump—shut off power and call a pro.

Check power and cable

Goal: Rule out power loss and cable issues before opening the robot.

  • Verify the transformer is plugged in and the circuit breaker has not tripped. Check for a tripped GFCI—press reset if needed. Confirm the transformer LED or indicator is on.
  • Check the floating cable for tangles around ladders, steps, or equipment. Untangle any loops. Inspect for cuts, cracks, or exposed wire. Replace a damaged cable per the manufacturer.
  • Confirm the pool water level is at least halfway up the skimmer. The robot must be fully submerged.
  • Good: Power is on, cable is clear, and water level is OK. Proceed to Filter and impeller.
  • Bad: Cable damaged or no power—fix or replace, then retest. If the breaker trips immediately, call a pro.

Filter and impeller

Goal: Clear blockages that prevent the robot from picking up debris.

  • Remove the robot from the pool. Open the filter compartment per your model. Empty the filter bag and rinse it with a hose. Reinstall and run a cycle.
  • If cleaning is still poor, unplug the robot and access the impeller. Check your owner’s manual or search “[brand] [model] robot pool cleaner impeller” for location. Remove leaves, hair, or debris. Rinse the housing. Reinstall and test.
  • Good: Filter was full or impeller was blocked—cleaning should improve.
  • Bad: Filter and impeller were clear—proceed to Tracks and brushes.

Tracks and brushes

Goal: Confirm the drive system is in good condition.

  • Inspect the tracks and brushes for wear, tears, or debris. Clean out leaves, pebbles, or hair wrapped around the axles. Replace worn tracks or brushes with exact-match parts from the manufacturer.
  • Good: Tracks and brushes are in good condition. The robot should move and clean.
  • Bad: Replaced parts but still not cleaning—call a pro.

When to get help

Call a pool equipment technician if:

  • The robot does not run at all with power and transformer confirmed.
  • It hums but does not move or pump (motor or drive fault).
  • The cable or housing is damaged and you cannot replace it safely.
  • You are not comfortable with electrical or mechanical repair.

Never work on electrical components with wet hands or while standing in water.

Verification

  • The robot runs, moves across the floor and walls, and picks up debris.
  • The filter bag is emptied after each run.
  • No tangles in the cable; no damage to the housing or cord.
  • The impeller spins freely and the tracks grip the pool surface.

Escalation ladder

Work from the device outward. Stop when the problem is fixed.

  1. Confirm symptom Verify the robot runs or does not; note if it picks up debris.
  2. Power and cable Check transformer, GFCI, and floating cable for tangles or damage.
  3. Water level and filter Confirm water level; empty and rinse the filter bag.
  4. Impeller and drive Inspect impeller for blockage; check tracks and brushes.
  5. Call a pro Robot does not run with power confirmed; hums but does not move or pump; cable or housing damaged.

What to capture if you need help

Before calling support or posting for help, have these ready. It speeds everything up.

  • Whether the robot runs or is silent
  • Whether it moves and picks up debris
  • Filter condition (full, clogged)
  • Cable condition (tangles, damage)
  • Impeller and track condition
  • Steps already tried

Does the robot run but leave debris behind, or not run at all?

Place the robot in the pool and start a cycle. If it runs but does not pick up debris, the filter or impeller may be blocked. If it does not run, power or the motor has failed.

Place the robot in the pool and start a cycle. Listen for the pump and watch for movement. Good: runs but leaves debris—filter or impeller. Bad: does not run—power or motor. Worse: hums but does not move or pump—shut off power, call a pro.

Runs but leaves debris Does not run

You can change your answer later.

Is power on and the cable clear?

Check transformer, GFCI, and floating cable before assuming motor failure.

Verify the transformer is plugged in and the GFCI has not tripped. Check the floating cable for tangles and damage. Good: power on and cable clear—proceed to water level. Bad: cable damaged or no power—fix or replace, then retest.

Yes No

You can change your answer later.

Is power on and the cable clear?

Rule out power and cable before checking filter and impeller.

Verify the transformer is plugged in and the GFCI has not tripped. Check the floating cable for tangles. Good: power on and cable clear—proceed to filter. Bad: cable damaged—replace per manufacturer.

Yes No

You can change your answer later.

Is the water level high enough?

The robot must be fully submerged. Water at least halfway up the skimmer.

Confirm the pool water is at least halfway up the skimmer opening. Place the robot in the pool—it should be fully underwater. Good: water level OK—proceed to filter. Bad: water too low—fill the pool and retest.

Yes No

You can change your answer later.

Fill the pool and retest

Fill the pool so the water is at least halfway up the skimmer opening. Place the robot in the pool and run a cycle. If it runs after filling, the low water level was the cause.

Done

Is the filter bag empty and clean?

A full or clogged filter bag reduces suction and cleaning.

Remove the robot from the pool. Open the filter compartment and empty the filter bag. Rinse with a hose. Reinstall and run a cycle. Good: filter was full—cleaning should improve. Bad: filter was clean—proceed to impeller.
Question

Was the filter full or clogged?

Continue

You can change your answer later.

Is the impeller clear of debris?

The impeller moves water through the robot. Blockage stops flow.

Unplug the robot. Remove it from the pool. Access the impeller per your model (owner's manual or search "[brand] [model] impeller"). Remove debris. Rinse and reassemble. Good: impeller was blocked—cleaning should improve. Bad: impeller was clear or damaged—check tracks and brushes, or call a pro.
Question

Was the impeller blocked?

Continue

You can change your answer later.

Are the tracks and brushes in good condition?

Worn tracks or brushes prevent movement and cleaning.

Inspect the tracks and brushes for wear, debris, or damage. Clean out wrapped debris. Replace worn tracks or brushes per the manufacturer. Good: tracks and brushes OK—robot should clean. Bad: replaced or still not cleaning—call a pro.
Question

Are the tracks and brushes in good condition?

Done

Call a technician

Call a pool equipment technician if the robot does not run with power and transformer confirmed, if it hums but does not move or pump (motor or drive fault), if the cable or housing is damaged, or if you are not comfortable with repair. Never work on electrical components with wet hands or while standing in water.

Done

Reviewed by Blackbox Atlas

Frequently asked questions

Why would a robot pool cleaner run but not pick up debris?
Common causes: full or clogged filter bag, blocked impeller, water level too low, worn brushes or tracks, or cable restricting movement. Empty and rinse the filter after each run. Check the impeller for debris. Confirm water level is at least halfway up the skimmer.
Can I fix a robot pool cleaner that will not clean myself?
Yes. Power checks, filter cleaning, cable untangling, and impeller inspection are DIY. Replacing the pump motor or drive unit requires opening the housing—call a pro if you are not comfortable. Never work on electrical components with wet hands or while standing in water.
When should I call a technician for a robot pool cleaner that will not clean?
Call a pool equipment technician if the robot does not run at all with power confirmed, if it hums but does not move or pump (motor or drive fault), if the cable or housing is damaged, or if you are not comfortable with electrical or mechanical repair.

Rate this guide

Was this helpful?

Continue to