Espa variable-speed pump display shows E04 and the motor will not run

Safety first: Turn off power before opening any part of the hydraulic circuit.

• 1. Check water level: Ensure the pool water level is at least halfway up the skimmer opening so the skimmer weir does not draw air.
• 2. Inspect valves: Confirm that the suction and return valves on the Espa pump manifold are fully open. A partially closed valve can cause low flow and trigger E04.
• 3. Prime the pump: Remove the prefilter lid, fill the Espa pump housing completely with water using a hose, reinstall the basket and lid, ensuring the lid O-ring is clean and lubricated with silicone grease. Restart the pump and observe for a solid water column in the pump housing.
• 4. Check for air leaks: Look for bubbles in the pump lid during operation. Inspect the suction unions, prefilter lid O-ring, and any threaded fittings for air leaks. Tighten unions and replace worn O-rings or apply PTFE tape to threaded fittings.
• 5. Clean suction lines: Backwash the filter if pressure is high, and clear skimmer baskets and main drain covers of debris.

If E04 continues despite good prime and no visible air, the flow sensor or pressure transducer in the Espa system may be faulty and require replacement.