Pump display shows E03 and the motor will not run or stops shortly after starting.

Safety first: Turn off the breaker and lock it out if possible. Verify power is off with a meter before opening the wiring compartment.

Steps to correct undervoltage:

• 1. Confirm nameplate voltage: Check the SuperFlo label for required voltage (typically 230 V for VS models). Ensure the breaker and supply match this rating.
• 2. Inspect wiring connections: Remove the motor wiring cover. Tighten all terminal screws and verify that the hot legs and ground are correctly landed as per the Pentair wiring diagram. Look for discoloration or melted insulation.
• 3. Measure line voltage: With power ON (use extreme caution), use a multimeter to measure voltage at the pump terminals. It should be within ±10% of the rated voltage. If it is significantly lower, there may be an issue upstream.
• 4. Check wire gauge and run length: Compare the installed conductor size and length to Pentair’s installation manual. Long runs with small gauge wire can cause excessive voltage drop. If undersized, have an electrician upgrade the wiring.
• 5. Verify breaker and panel connections: Inspect the breaker for signs of overheating or looseness. Tighten lugs and replace a suspect breaker as needed (by a qualified person).

If E03 continues with correct voltage at the terminals, the drive electronics may be misreading voltage and the motor/drive assembly may need replacement.