KitchenAid Dishwasher fill up with water after use
Is the water clean water or dirty water? This may sound like an ignorant question, but it can make a difference.
If the water is clean water, it sounds like you could have a bad fill valve. If the dishwasher is filling with water when it is not running, chances are the fill valve is leaking. The valve is closed when the float switch senses the tub filling to a certain level. The valve is also closed when not energized by the control board during drain, drying and off cycles. However, if the valve diaphragm is not seating properly when closed, it will continue to leak by. That's probably why you don't notice it while is running and it has a chance to fill during the night when not in use. Here's what to look for:
With the dishwasher off, take a towel and dry the tub as much as possible. Now, locate the fill port where the water comes in (usually on the left hand side of the tub). Watch this fill port closely for several minutes to see if water is running in. It could be as minute as a trickle or drip. If any water is coming in at all, the fill valve should be replaced.
Now, another problem that can occur is when you notice dirty water staying in the tub or overflowing. This is usually caused by a bad check valve in the drain pump that's allowing water to leak back from the sink into the tub. Or, you do not have a high loop in the drain line. Here's what to look for:
Check to make sure the drain line has a high loop as it leaves the dishwasher and before it gets to the drain pipe at the sink. That is, make sure the drain hose is looped above the trap in the sink and not laying under the sink somewhere.
You can also try filling the sink with water and open the dishwasher door. Drain the sink to see if anything is getting fed back into dishwasher. If you see water starting to fill in the tub, chances are you could have a bad check valve. Some dishwashers have a check valve in the drain pump, while other models have the check valve located in the drain hose itself. Some don't have one at all. That's why the positioning of the drain hose can be important.
Good luck to you and I hope this may help. If you determine a cause, post back with comments if you need advice on how to replace anything.
on Feb 11, 2019