Espa variable-speed pool pump will not start and shows E03 on the display

Safety first: Isolate power at the main breaker. Only qualified persons should open electrical panels.

• 1. Visual inspection: Check the Espa control box and terminal cover on the motor. Look for burnt wiring, loose screws, or discoloration at the L1, L2, L3 terminals.
• 2. Tighten terminals: With power off, tighten all phase and earth connections at the pump terminal block and in the external control panel feeding the pump.
• 3. Check fuses and breakers: Inspect any three-phase fuses or miniature circuit breakers dedicated to the pump. Replace blown fuses with the correct rating specified for the Espa model.
• 4. Measure phase voltages: With power restored and using a multimeter (electrician only), verify that all three phases are present and balanced at the pump terminals. Any missing or significantly low phase will trigger E03.
• 5. Inspect contactor: If a motor contactor is used, check that all three poles close properly and that there is no burnt contact. Replace the contactor if one pole is defective.

If E03 persists with correct supply, the internal drive or control PCB may be faulty and should be evaluated by an authorized Espa service center.