Troubleshooting guide
Dolphin not covering entire pool
Double-check before purchasing
- Recommended cycle duration by pool size varies between Dolphin model generations — consult your model-specific manual.
The Problem
When a Dolphin finishes a cycle but leaves sections of the pool uncleaned, it is usually because the cable is restricting its range, the cleaning cycle time is too short for the pool size, or the robot's navigation is being disrupted by a mechanical fault.
Steps
- 1
Measure your pool's longest diagonal (corner to corner). Confirm the cable is long enough to cover this distance with slack.
- 2
Straighten the full cable before each use and confirm no part is caught on pool fittings, steps, or the skimmer.
- 3
Check your cleaning cycle time setting. Increase to the longest available cycle for a large or complex-shaped pool.
- 4
Watch the robot for the first 5 minutes of the cycle. If it is moving in circles or getting stuck in one area, those are separate issues to fix first.
- 5
Try starting the robot from a different position in the pool — opposite end or the centre — and see if coverage improves.
💡 On some models, the starting position significantly affects which path the algorithm selects.
- 6
Inspect the drive belts and tracks for uneven wear. A belt that has partially stretched on one side will cause a coverage bias.
Possible Causes & Solutions
Cable too short or tangled, restricting the robot's range
Measure the pool's longest diagonal. The cable should be long enough to reach the far corner with slack to spare. A tangled or short cable prevents the robot from reaching far sections.
Cycle time set too short for the pool size
Most Dolphin models have 1.5-hour, 2-hour, and 3-hour cycle options. Large pools need longer cycles. Consult your model manual for recommended cycle time by pool size.
Robot spinning in circles instead of covering the pool systematically
If the robot drives in circles, it is not following its cleaning grid. Inspect the tracks and drive belts for uneven traction. See the circular movement guide for full diagnosis.
Algorithmic navigation disrupted by unusual pool shape
Very irregular pool shapes — L-shaped, pools with many alcoves, or pools with large steps — can confuse the navigation algorithm. Try starting the robot from different positions on alternate cycles.
Robot consistently getting stuck in one area
If the robot repeatedly gets stuck in a corner or on a step, it spends its cycle time trying to escape rather than cleaning. Identify the trap zone and adjust cable placement or pool entry position.
When to Replace
Replace drive belts when cracked or stretched. Replace the cable assembly if it cannot reach the far end of the pool with slack — do not add extension cables as this can cause electrical faults.
Where to Buy
Find compatible replacement parts from these retailers:
Compatible Parts
Full Cable Assembly
Available in 10m and 18m lengths. Confirm your model's cable length before ordering.
Drive Belt Kit
Model-specific — confirm compatibility before ordering.
Frequently Asked Questions
Can the robot's navigation algorithm be updated to improve coverage?
Some Dolphin models support firmware updates via the MyDolphin Plus app or a Maytronics service centre. Check whether a firmware update is available for your model.
My robot cleans the same half of the pool every time. Why?
This usually indicates a cable or traction imbalance pulling the robot toward one side. Check cable tension and inspect the drive belts and tracks for uneven wear.
Should I use a shorter or longer cycle for coverage problems?
Always use the longest available cycle for a coverage problem. A short cycle simply runs out of time before the robot finishes the pool.
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