Dishwasher Not Cleaning

Photo of dishes ins a dishwasher with water splashing

In this article we will discuss a dishwasher not cleaning the dishes properly. For the purpose of this discussion I will assume that there is not a mechanical problem with your dishwasher. In other words, there is enough water going into the dishwasher, the pump is working properly and the dishwasher is pumping all the water out.

What I will focus on is what I have experienced countless times over the years as the number 1 reason a dishwasher is not cleaning. I cannot tell you how many times I've been called to a customer's home because they called in and said the dishwasher was not cleaning properly when it turned out that the dishwasher was not broken.

If your dishwasher is not cleaning well there are a few things you can do to help the dishwasher do a better job. A lot of folks don't believe that they should have to wash their dishes before they put them in a dishwasher. That does not mean that you don't have to scrape the leftovers off your dishes. I agree that you should not have to wash your dishes before you put them in the dishwasher. Loading a dishwasher properly will certainly result in cleaner dishes. On most dishwashers the most aggressive wash action is going to be found on the bottom rack just above the bottom wash arm. And that is where you want to put the dishes that need the most cleaning.

I personally would never use a liquid detergent in a dishwasher and that includes the so-called gel detergent. That's because I have seen too many dishwashers with a build up of this liquid detergent that causes problems. I only use granular detergent or the granular tablets.

All of that having been said, the absolute most important thing you can do when your dishwasher is not cleaning properly is to turn your hot water tank up. In an effort to conserve energy, a lot of folks set the temperature of the water at their hot water heaters to 120 degrees. Well I've got some news for you, 120 degree water at the hot water heater does not mean 120 degree water at the dishwasher. Consider the distance between your dishwasher and your hot water heater.

The fact is with today's dishwashers using such little water in the wash cycle, it is possible that the water line between the dishwasher and the hot water heater holds enough water to fill a dishwasher. That means the dishwasher will not get a drop of water from the hot water heater. Whatever the distance, you should turn the hot water on at your kitchen sink and let it run until it is as hot as it can be before you start the dishwasher. This will purge all the water out of the line that is cold and hopefully your dishwasher will fill with the hottest available water.

The bad news is that if your hot water heater is set for 120 degrees it's still not going to be hot enough. I personally have my hot water heater set at 130 degrees. The distance between my dishwasher and the hot water heater is not very far so I don't bother purging the line. In addition to that, I have a Bosch dishwasher which has an external water heater that bumps the water temperature up and does a fantastic job.

Assuming that your dishwasher is functioning as it did when it left the factory, the bottom line is if you want clean dishes in your dishwasher at the end of the cycle, you're probably going to have to switch to granular detergent and turn up your hot water heater.