Detergent dosing error; machine reports E11 and dishes are either not clean or show excessive foam.

Safety first: Wear gloves and eye protection when handling commercial detergents.

• Check detergent level: Ensure the external detergent drum or container is not empty. Replace or refill as needed.
• Inspect suction tube: Verify that the suction tube reaches the bottom of the container and is not kinked or blocked. Clean or replace the foot filter if fitted.
• Prime the pump: Some Comenda models allow manual priming of the detergent pump via the control panel. Run the priming function until detergent is visible in the line.
• Check dosing pump operation: During a wash cycle, observe whether the detergent pump runs. If it does not run but has supply voltage, replace the pump.
• Adjust dosing: If dishes are over-foaming, reduce the pump run time or stroke length according to the service manual.