Newly remodeled house, new-looking dishwasher: Brown spots on our dishes

We moved into a newly remodeled house with a new-looking dishwasher two years ago. We noticed that the dishwasher didn’t quite get our dishes clean; it left some brown spots and residue on our dishes, most noticeably on our white Corelle Ware plates and bowls. We thought it was just a cheap dishwasher.

Dishwasher could put brown spots on clean dishes!

To figure out what was going on, I tried washing a load of dishes that we had thoroughly rinsed so there was no food residue left. Somehow the dishwasher managed to put the brownish spots on the dishes even though there was no dirt on them to begin with. That should have been my clue.

Replaced dishwasher AND installed an under sink water filter: Brown spots continue

We replaced the dishwasher anyway with a nice mid-grade stainless steel Maytag dishwasher. The brown spots on our plates and bowls continued. Internet searches suggested that the spots were rust, dirt, or some sort of sediment from incoming our water line. So I installed a $40 Whirlpool under sink water filter. The brown spots continued to appear.

At this point I had eliminated both the dishwasher itself and the incoming water as the problem. By process of elimination that left the drain as the culprit. My dishwasher drains into the garbage disposal. Could dirt be migrating from my garbage disposal into my dishwasher?

We paid close attention after that, and it seemed like the more we used our garbage disposal, the more brown spots the dishwasher put on our dishes when we ran our dishwasher.

The fix: Looping the dishwasher drain hose up high

After some more searching revealed that other people had cleaner dishes after replacing their garbage disposals, I ran across some advice to loop the dishwasher drain hose up high under the sink before connecting it to the garbage disposal.

I disconnected the drain hose and looped it up over the water pipes for the faucet in order to hold it in place before reconnecting the dishwasher drain hose to the garbage disposal. Previously the drain hose had just come up directly to the garbage disposal, so any junk from the garbage disposal could flow down into the dishwasher.

Over the next several months, the brown spots on our dishes gradually decreased. I think it took repeated cycles of the dishwasher to clean out the junk from the garbage disposal that had accumulated in the dishwasher drain hose. If you are having a similar problem, you could try replacing the drain hose and hopefully that would fix the problem immediately.

Have you had a similar problem? What did you do to fix it?