Hi,
From the tech sheet for your model washer.
No water supplied to washer.1. Check water connections to washer.
2. Verify hot and cold water supply is on.
Plugged filter/screen.Check for plugged filter or screen in the water valve or hoses.
Drain hose installation.Check for proper drain hose installation.
Valve problem.See TEST #2: Valves, page 13.
Main control problem.See TEST #1: Main Control, page 12.
Whirlpool Washing Machine Model WTW4820XQ0 PartsTech sheet sent via PM, to large for me to attach to this topic.
Hope that helps. Let us know what you find wrong or if you have any other questions.