Pump stops during operation and displays E03 after running for several minutes

Safety first: Turn off power at the breaker and allow the pump to cool for at least 20–30 minutes before touching the motor.

• Check ventilation: Inspect the Aquaflow motor housing. Clear away leaves, dirt, or obstructions blocking the cooling fins or fan vents. Ensure the pump is not enclosed in a tight, unventilated box.
• Verify fan operation: With power off, look through the rear motor vents and confirm the plastic cooling fan is intact and not rubbing. Spin the shaft by hand; you should hear the fan move freely.
• Check valve positions: Ensure suction and return valves are fully open. A restricted flow can cause the pump to work harder and overheat.
• Ambient temperature: If the pump is in direct sun or a small shed, consider adding shade or ventilation. Excessive heat can trigger E03.

After cooling and clearing obstructions, restore power and test. If E03 recurs quickly, the internal thermal sensor or motor windings may be failing; consult a technician for motor testing or replacement.