Washer shows F15, often associated with heater or drying function on washer-dryer combo models.

Safety first: Unplug the appliance and allow any heating components to cool fully before servicing.

Step-by-step:

• Access heater area: On combo units, the drying heater is often located in a duct assembly at the rear or side of the cabinet.
• Check thermal fuses and thermostats: Use a multimeter to test continuity across thermal fuses and thermostats in the heater circuit. Replace any that are open.
• Test heater element: Measure resistance across the heater terminals. An open circuit indicates a failed heater.
• Inspect wiring: Look for burnt connectors, loose terminals, or melted insulation in the heater wiring harness.
• Control board: If all heater components test good, the heater relay or control circuit on the main board may be faulty and require board replacement.

When to call a technician: Heater circuits involve high wattage and can be hazardous if misrepaired. Professional diagnosis is recommended if you are not experienced with high-voltage heater circuits.