Richard H Portage , MI July 21, 2021 Appliance: Whirlpool Gas Dryer WGD6400SW0 Whirlpool Dryer Wgd6400sw0: The burner would ignite but wouldn't restart during the drying cycle. How to replace Dryer Gas Valve Coil Kit. Used the online videos to diagnose the problem. Purchased the parts, followed the step by step directions from the video, dryer fixed!! Less than $100 of parts in lieu of buying a new dryer!! Do-It-Yourself Rating: Repair Time Estimate: 30-60 minutes