Lemme guess, you keep opening up your dishwasher, and you know that they last time you peeked inside there was no water left, but you keep seeing standing water in the dishwasher, don’t you? Well there are a few reasons why this happens, as I have dealt with this problem literally hundreds of times, and I do one thing to get rid of standing water in dishwasher once and for all, and let me tell you that it works about 95% of the time. Most of the time your problem is that the drain hose is not mounted properly, which if you know a thing or two about the gravity of water and how it flows, when you run water from your sink, your dishwasher is going to fill up with water unless you have the drain line mounted above where the water fills up. Look at this picture for example, this is a dishwasher that always seemed to have standing water in it, even when it was not in use.
Now in case you did not know your drain line is coming out of the garbage disposal here, right above the white piping which is the drain line for the sink. When the dishwasher goes through the drain cycle, it will drain the water into the garbage disposal using the motor, the way that this is set up, not all of the water is going to get drained properly and some will go back inside of the dishwasher. Also, if you are running the water in the sink, there is a good amount that is going to go down that drain line, as this is how gravity works. All we have to do to fix this is mount the dishwasher drain line, above the garbage disposal, where most of the water accumulates at from both the drain cycling and using the kitchen faucet to rinse dishes or whatever. This is how the dishwasher drain line should be mounted so that there will no longer be any standing water in dishwasher.
Now this will prevent dirty water from going back into the dishwasher. What I used to mount the line was a piece of metal stripping and two screws into the wall. You do not necessarily have to use the exact same thing as I did, but it was the only thing that I had on hand at the time. Many new dishwasher drain hoses come with a plastic loop around the hose that has a hole in it, guess what that is used for, mounting the dishwasher line! As I said, whenever I get a service request about standing water in dishwasher, this solves the problem 95% of the time.
Now there is one more thing wrong with this dishwasher drain line that could potentially cause a problem in the future, can anyone see what it is?