Washer-dryer combo displays E12 and drying performance is poor; cycle ends quickly with damp clothes.

Safety first: Unplug the unit before cleaning internal ducts or accessing sensors.

• Clean lint filter: Remove and thoroughly clean the lint filter after every drying cycle. Wash with warm water and mild detergent if coated with fabric softener residue.
• Inspect air ducts: Remove rear or top cover to access the dryer air path. Vacuum lint from ducts, blower wheel, and heater housing.
• Check condenser (if equipped): On ventless Costway combos, remove the condenser unit (usually behind a front panel) and rinse it under running water to clear lint and scale. Allow to dry before reinstalling.
• Clean moisture sensor bars: Inside the drum, locate the metal sensor strips (often near the door opening). Wipe them with a cloth dampened with white vinegar to remove residue that can prevent accurate sensing.
• Inspect sensor wiring: Access the back of the sensor assembly and ensure the harness is firmly connected and not corroded.
• If E12 persists: Replace the moisture sensor assembly. If airflow and sensors are good, the control board's drying algorithm may be faulty and require replacement.