Pump controller displays E08 and the motor stops; often occurs when the pump starts under heavy load.

Safety: Isolate power before opening the motor terminal box or control panel.

• Check for mechanical drag: Ensure the impeller spins freely and there is no rubbing on the diffuser or volute.
• Inspect start capacitor: On single‑phase Certikin pumps, open the capacitor housing and visually inspect the capacitor for bulging or leakage. Test capacitance with a meter and replace if out of tolerance.
• Verify cable size: Confirm that the supply cable size and run length meet Certikin's installation recommendations to avoid voltage drop during start.
• Soft start settings: If using a variable speed drive, adjust the acceleration time to be slightly longer to reduce inrush current.

If overcurrent persists after mechanical and electrical checks, the motor windings may be partially shorted and the motor should be replaced.