E07 displayed and the unit indicates a drain or backwash fault

Safety first: Turn off power and close inlet/outlet valves before disconnecting the drain line. Be prepared for water discharge.

• Inspect drain hose: Follow the hose from the valve to the drain. Straighten any kinks or sharp bends. Ensure the hose rises and falls according to Monarch installation guidelines.
• Check for blockages: Remove the hose from the valve and from the drain point. Flush it through with mains water until it runs clear. Replace if heavily scaled or damaged.
• Clean drain flow control: Many Monarch valves have a small drain flow restrictor or button. Remove it carefully, soak in descaler, rinse, and reinstall.
• Verify drain termination: Ensure the hose discharges into an open standpipe or tundish with an air gap. If the standpipe is blocked, clear it or consult a plumber.
• Test backwash: Restore water and power, then start a manual regeneration and observe the drain flow. If E07 reappears, the internal valve passages may be obstructed and require professional service.