E13 displayed, drain water continues to run or unit cannot complete regeneration

Safety: Isolate the softener and relieve pressure before opening the valve head. Drain water may be discharged at high flow—ensure the drain line is secure.

• Confirm symptom: With the unit in service mode, check the drain hose. There should be no continuous flow. If water is running, the drain valve is not sealing.
• Inspect drain line: Ensure the drain hose is not routed too high or submerged in standing water, which can cause siphoning. Correct the routing if necessary.
• Valve inspection: Remove the Cillit control head cover and inspect the rotor disc and seal pack. Debris or worn seals can prevent proper closure of the drain port.
• Clean and reseat: Disassemble the valve according to the Cillit service manual, clean all ports, and reinstall with a new Cillit seal and spacer kit if seals are flattened or torn.
• Test operation: Reassemble, restore water and power, and run a manual regeneration to confirm that the drain only flows during backwash and brine draw stages.