Someone had a dishwasher question and it triggered mine. I've noticed that water gathers in bottom of the dishwasher when it is not in use. Not a lot, an inch or two. Dirty water I think. The exhaust hose of the dishwasher is hooked up to the drainage pipe from the kitchen sink, which seems appropriate. The hose from the dishwasher goes up from the dishwasher to near the bottom of the sink and then down and attaches to the pipe.
What I think is happening is that the hose does not go up far enough. So, when water rises in the sink, water rises in that hose, goes over the highest part, and down into the dishwasher.
I'm guessing that either some one-way valve is shot or there isn't a valve in the first place. Am I correct in thinking that this is the problem and that putting in a longer hose with a higher top, somewhere near the top of the sink, will prevent water from entering the dishwasher?