E07 error and water continuously drains to the waste line

Safety: Turn off power and close inlet and outlet valves. Open a faucet to relieve pressure before opening the valve head.

• Confirm symptom: Check the drain hose from the Aqmos softener. If water flows to drain even when not regenerating, the valve is not sealing.
• Inspect drain line: Ensure the drain line is not routed too high or submerged in standing water, which can cause backpressure and improper valve seating.
• Disassemble valve head: Remove the control head cover and access the main piston and seal pack (refer to Aqmos exploded view). Carefully pull the piston assembly out.
• Clean and inspect: Rinse the piston and internal bore to remove grit. Check seals and spacers for cuts, flattening, or deformation. Replace the seal and spacer kit if worn.
• Check drain valve seat: Inspect the drain port and seat for damage or foreign objects. Clean thoroughly.
• Reassemble and test: Reinstall the piston and seals, ensuring correct orientation. Restore water and power, then check that drain flow stops in service mode. If E07 persists, the valve body or control head may need replacement.