Last Saturday I set up to filter the last 15 gallons of my bulk 2020 stored syrup. Reheated my syrup in 5 gallon batches in my huge 30l stock pot, added the DE, and started to pump (manually) through the filter back into the stock pot. Usually, within a minute, the syrup is sparkling clear, so then the hose goes into the bottler. But this time, no dice. I filled a jar to take a closer look. It was just as cloudy as the syrup in the stock pot. I kept pumping thinking the plates needed time to fill up, but no change. Everything seemed to be normal; no leaks, flow the same. ???
I finally gave in the broke down the press (no so much fun when it's 200F). I took the plates off one at a time, expecting to find a blown out paper. But there was none. One paper had a small tear on the outside edge which would not have been exposed to the open area inside the plate, and I may have torn it pealing off the paper. The plates were not full, but I had not run more than a few gallons through. Papers were coated about 1/4 inch, but not evenly, and the back plates not as much. It's not possible to put this press together wrong, due to the design. So I still had no evidence of what might have happed.
Everything was cleaned and reassembled with new papers. I added about 2 cups more DE to the pot and started pumping again. Within a few seconds, the syrup was sparkling clear. And so it went until I finished filtering all the remaining syrup.
Anyone ever have anything like that happen? I saved the papers and will take another look. Barring a mechanical assembly error, it seems like one or more has to have failed, allowing the cloudy syrup to pass through.