Display shows E02 and the unit fails to draw brine during regeneration

Safety first: Disconnect power and close the inlet and outlet valves. Open a nearby tap to relieve pressure before opening the valve body.

• Check brine level: Ensure there is adequate water in the brine tank to cover the air check at the bottom of the brine well. If the tank is completely dry, refill according to the Monarch manual and restart a regeneration.
• Inspect brine line: Follow the small tube from the brine tank to the Monarch valve. Check for kinks, blockages, or damage. Remove the tube at both ends and blow through it; it should be clear. Replace if restricted.
• Clean venturi/injector: On the control valve, locate the injector/venturi housing (often under a cap held by screws). Remove the cap and carefully take out the injector and nozzle. Soak in warm water with a little vinegar to dissolve scale, then rinse thoroughly and reassemble in the correct orientation.
• Check brine valve and air check: Inspect the brine valve assembly in the valve head and the air check at the bottom of the brine well for salt sludge or debris. Clean gently and ensure free movement.
• Test regeneration: Restore water and power, then start a manual regeneration and observe the brine draw stage. If E02 reappears, the control valve may require professional service.