A non-working motor is most commonly caused by saltwater crystallization locking the propeller shaft
A non-working motor is most commonly caused by saltwater crystallization locking the propeller shaft, or debris wrapped around the propeller. Fix: turn the robot off, manually rotate the lower propeller by hand to break the jam, rinse thoroughly with fresh water, and restart. Only goes in reverse? Check both propellers and update firmware. Grinding noise? Clear debris from the impeller chamber. Only goes in reverse? Check both propellers and update firmware. Grinding noise? Clear debris from the impeller chamber.
Saltwater Crystallization
If you use the EcoSurfer S2 in a saltwater pool, mineral deposits can form on the propeller shaft and cause the motor to appear seized. To resolve: (1) Remove the robot from the pool. (2) Turn off the device. (3) Observe the propeller rotation — if jammed, manually rotate the lower propeller counterclockwise to break the salt crust. (4) Rinse the propeller area thoroughly with fresh water. (5) Power on and test rotation before returning to pool.
Debris Wrapped Around the Propeller
Hair, string, or fine pool netting can wrap around the propeller shaft and stall the motor. Turn off the device, use a thin tool (not sharp) to carefully remove any wrapped debris. Never use scissors or a blade near the rubber propeller blade — cuts permanently reduce propeller efficiency.
Left Motor Not Responding After Cleaning
If only the left motor is non-functional after cleaning the propeller: (1) Restart the device. (2) Test in the pool for 2–3 minutes. If the motor remains dead after restart, this indicates an internal motor failure within the warranty period. Contact Aiper support with purchase date and serial number.
Saltwater Pool Maintenance Tips
After each session in a saltwater pool: (1) Rinse the entire robot with fresh water (focus on propeller area). (2) Allow to air-dry before storing. (3) Once per month, soak the propeller area in fresh water for 10 minutes to dissolve residual salt deposits. This prevents crystallization buildup and extends motor life significantly.
Robot Only Goes in Reverse or Spins in Circles
If the EcoSurfer S2 only moves backwards or spins in one direction: (1) Check for debris wrapped around both propellers, not just the obvious one. A single wrapped propeller causes asymmetric thrust and circular movement. (2) Check the firmware version in the Aiper app. Version v5 firmware has a known directional bug — update to v6 or later (Device Info → Firmware Update). (3) If both propellers are clean and firmware is up to date, one motor driver may have failed. This is a warranty-covered defect — contact Aiper support with a video of the behavior.
Robot Avoids Pool Edges — Stops 18 Inches from Walls
The EcoSurfer S2 uses optical sensors for obstacle avoidance. Stopping approximately 18 inches from the pool edge is normal behavior — the sensors detect the wall and trigger an early turn to prevent collision. This is by design. If you need closer edge cleaning: (1) Ensure the device is in Full mode (not Eco mode) in the app. (2) Check for black or very dark-colored pool walls or obstacles — the optical sensors may not reliably detect dark surfaces. In this case, the robot may behave unpredictably near dark walls. (3) If edge avoidance is excessive (stopping 3+ feet from walls), clean the sensor windows with a damp cloth — dirty sensors reduce detection range.
Unusual Noise During Operation — Grinding or Rattling
A grinding or rattling noise usually indicates: (1) Debris in the impeller. Turn off the device, remove the bottom cover, and check the impeller chamber for small stones, sand, or leaf fragments. (2) Worn bearing. If the noise is a consistent whine that changes pitch with motor speed, a propeller shaft bearing may be worn. This typically occurs after 12+ months of heavy use. Contact Aiper support for bearing service — continued use with a worn bearing can damage the motor. (3) Cavitation. A brief rattling when first placed in the water is normal air purging from the impeller chamber — it should stop within 10–15 seconds.
Robot Only Goes in Reverse or Spins in Circles
If the EcoSurfer S2 only moves backwards or spins in one direction: (1) Check for debris wrapped around both propellers, not just the obvious one. A single wrapped propeller causes asymmetric thrust and circular movement. (2) Check the firmware version in the Aiper app. Version v5 firmware has a known directional bug — update to v6 or later (Device Info → Firmware Update). (3) If both propellers are clean and firmware is up to date, one motor driver may have failed. This is a warranty-covered defect — contact Aiper support with a video of the behavior.
Robot Avoids Pool Edges — Stops 18 Inches from Walls
The EcoSurfer S2 uses optical sensors for obstacle avoidance. Stopping approximately 18 inches from the pool edge is normal behavior — the sensors detect the wall and trigger an early turn to prevent collision. This is by design. If you need closer edge cleaning: (1) Ensure the device is in Full mode (not Eco mode) in the app. (2) Check for black or very dark-colored pool walls or obstacles — the optical sensors may not reliably detect dark surfaces. In this case, the robot may behave unpredictably near dark walls. (3) If edge avoidance is excessive (stopping 3+ feet from walls), clean the sensor windows with a damp cloth — dirty sensors reduce detection range.
Unusual Noise During Operation — Grinding or Rattling
A grinding or rattling noise usually indicates: (1) Debris in the impeller. Turn off the device, remove the bottom cover, and check the impeller chamber for small stones, sand, or leaf fragments. (2) Worn bearing. If the noise is a consistent whine that changes pitch with motor speed, a propeller shaft bearing may be worn. This typically occurs after 12+ months of heavy use. Contact Aiper support for bearing service — continued use with a worn bearing can damage the motor. (3) Cavitation. A brief rattling when first placed in the water is normal air purging from the impeller chamber — it should stop within 10–15 seconds.