E05 error appears and regeneration stops in mid-cycle

Safety: Disconnect power. Close inlet valve and place the softener in bypass before opening any drain connections.

• Inspect drain hose: Follow the drain hose from the Idrobase valve to the drain point. Ensure it is not kinked, crushed, or routed higher than recommended. Straighten or reroute as needed.
• Check drain air gap: If an air gap fitting is used, remove and clean it. Clear any sludge or scale that may restrict flow.
• Clean drain port: Remove the drain line from the valve. Inspect the drain port for resin beads or debris. Flush with water and a small brush. Do not enlarge the port.
• Flow test: With the unit in manual backwash (refer to manual), briefly open the inlet while the drain line discharges into a bucket. Confirm strong flow. If weak or none, the internal valve may be blocked and require disassembly and cleaning.
• Restore operation: Reconnect drain line securely, ensuring a proper air gap and slope to the drain. Reset the error and run a full regeneration.