E7 error and brine tank does not fill with water before regeneration

Safety: Unplug the unit and place it in bypass before working on the brine system.

• 1. Check brine tank water level: After a scheduled regeneration, there should be a small amount of water in the brine tank. If it is completely dry, suspect a fill issue.
• 2. Inspect brine line: Follow the brine line from the control valve to the brine tank. Look for kinks, pinched sections, or air leaks at fittings. Straighten or replace as needed.
• 3. Clean refill orifice: Many RainSoft valves use a small orifice or flow control for brine refill. Remove it and soak in vinegar to dissolve scale. Rinse thoroughly and reinstall.
• 4. Test brine fill solenoid: During the brine fill stage (consult manual for timing), measure voltage at the brine valve coil. If voltage is present but no water flows, the valve is stuck or failed and should be replaced.
• 5. Verify water supply pressure: Ensure adequate pressure (typically 40–80 psi). Very low pressure can prevent proper brine fill.

Note: If there is no voltage at the brine valve during fill, the control board output may be defective and require replacement.