The first thing to check when water is flowing into the GE Duet washer, even when the washing machine is turned off is the drainpipe, which is also called the standpipe. If the drain hose is pushed too far into the drainpipe or the laundry tub, it can cause water to siphon into the washing machine after the cycle is complete instead of draining correctly. Pull the drain hose back so no more than 8 inches of the drain hose extends into the laundry tub or the standpipe.
Check the method used to connect the drain hose into the standpipe. If the drain hose is taped onto the standpipe or the standpipe is covered with tape, there is no air gap. An air gap is necessary for proper drainage and to prevent water from entering the machine when the water should be draining out or already drained.
If the drain hose is obstructed, water may not be able to flow freely through the hose and can end up backing into the washer. Set towels on the floor behind the washer and apply a wrench in a counterclockwise direction to disconnect the drain hose from the washing machine. Examine the hose for possible debris or obstructions and clear by flushing with water or shaking the hose hard. When all obstructions are clear, connect the drain hose to the washer with the wrench in a clockwise motion.
The Whirlpool washing machine has a fill valve that opens and closes to allow water into the washing machine automatically. If the fill valve gets stuck in the open position, water will enter the washer even when the machine is not turned on. Try disconnecting the power cord to the washer and wait to see whether water continues to flow into the unit. If water keeps flowing, turn off the water faucets and contact Whirlpool for service to replace the fill valve.