Dryer does not heat; F4 error appears after a few minutes of operation.

Safety first: Disconnect power and wait for all internal components to cool. Heating components can remain hot for some time.

• Check airflow first: Ensure the lint filter and exhaust duct are clean and not blocked. Poor airflow can overheat and trip safety devices.
• Access the heater assembly: Remove the rear panel or side panel (depending on model) to reach the heater housing.
• Inspect wiring and terminals: Look for burnt connectors or loose spade terminals on the heater and thermostats. Tighten or replace damaged connectors.
• Test the heating element: Disconnect the heater leads and measure resistance across the element. An open circuit indicates a failed element that must be replaced.
• Check thermal cut-out and thermostats: Test each thermostat and thermal fuse for continuity. A blown thermal fuse will read open and must be replaced; investigate and correct any airflow issues before replacing.
• Reassemble and test: After replacing faulty parts, reassemble, restore power, and run a warm cycle to confirm proper heating and that F4 does not reappear.