In the spring of 2014 I started getting a rubbery residue in my dishwasher. This isn’t the calcium powder from hard water, but a stretchy gray substance. The technician that came out cleaned it up but had never seen anything like it. When it came back a few months later I did some web searches and finally found a forum post from someone who had the same problem. He had a different dishwasher but he had hard water (check) and was using Costco “non-phosphate” dishwasher detergent (check). So I posted in the same forum to see if this person had found a solution. He responded that the problem went away when he started using “Bubble Bandit” detergent. BB still has phosphates because it is a commercial product while all the consumer brands had to eliminate phosphates last fall. Apparently this is when my problem started.
So my solution was to go down to Nichols and get a small box of Trisodium phosphate (TSP) powder. I sprinkle a bit on top of the detergent with every other load. From what I have read that is the equivalent of putting phosphates back into your detergent. And now the gunk is gone. Has anyone else has seen this?
I just disassembled my dishwasher to diagnose a suspicious noise and discovered it. It looked like someone had spilled pale gray latex paint in the inner workings. A web search turned up this blog post, your exchange with the guy with the Gaggenau, and very little else. I would love to know the science behind the goo.
Can’t help you there, Joe, but when Costco stopped selling Kirkland Dishwasher detergent I went back to Cascade and I no longer had to add TSP. Something about the combination of hard water and cheap dishwasher detergent.