Excessive foam or suds in the recovery tank, vacuum sound changes, and suction stops intermittently.

Safety first: Unplug the machine before emptying tanks.

• Empty and rinse recovery tank: Remove all foamy water and rinse the tank thoroughly to remove detergent residue.
• Use correct detergent: Only use Nilfisk‑approved low‑foam carpet extraction chemicals at the recommended dilution.
• Add defoamer: If allowed by the manufacturer, add a small amount of defoaming agent to the recovery tank to control foam.
• Clean float assembly: Ensure the recovery float moves freely and is not stuck in the closed position due to dried foam.