Harvey K Sitka , AK August 01, 2020 Appliance: Whirlpool Electric Dryer WED9400SW2 Whirlpool Dryer Wed9400sw2: Dryer would not start. First thought it was safety switches. Had to take it all apart to trace wires. Found door switch open. How to replace Dryer Thermistor. Waiting for new door switch.. Do-It-Yourself Rating: Repair Time Estimate: 2+ hours