Digital control on Pahlén pool pump controller shows E01 and pump will not start

Safety first: Turn off all power at the pool equipment breaker before opening any part of the pump or plumbing. Never run the pump dry.

• Check water level: Ensure the pool water level is at least halfway up the skimmer opening so the skimmer does not draw air.
• Inspect skimmer and pump basket: Open the skimmer lid and remove leaves/debris. Then open the pump strainer lid on the Pahlén pump, remove the basket, and clean it thoroughly. Reinstall correctly and ensure the lid O-ring is clean and lubricated.
• Verify valves: Confirm that all suction and return valves feeding the Pahlén pump are fully open. Partially closed valves can cause low flow and trigger E01.
• Check the filter: If you have a Pahlén filter or compatible sand/cartridge filter, check the pressure gauge. If pressure is high, backwash (sand) or clean/replace (cartridge) the filter to restore flow.
• Prime the pump: Fill the pump strainer housing with water, reinstall the lid, open any air bleed on the filter, then restore power and start the pump. Watch for a solid flow of water within 1–2 minutes.
• Clear the error: Once normal flow is restored, reset the controller (power cycle or reset button per Pahlén control panel instructions) and confirm E01 does not reappear.

If E01 persists despite good water flow, the flow sensor or control board may be faulty and should be checked by a qualified technician.