My clothes washer seems to be draining erratically. Let me first explain that I thoroughly cleaned the entire drain system with household vinegar including the boot at the bottom of the tub, drain ball. pressure sending unit, debris filter, pump and motor assembly, and discharge hose. After reassembling the drain system, I ran the washer through two "Clean Washer" cycles: the first with bleach, as directed, and the second with half a gallon of vinegar.
The machine performed both clean cycles perfectly. I am convinced the machine is suds free.
Now the troubles begin. I first ran a "Drain and Spin" load with clean, but wet socks and tee shirts, it was competed in the 15 minutes. Then, with the same small amount of suds free clothes, I ran the "Rinse and Spin" cycle with no fabric softener. At the 16 minutes remaining mark it failed to drain completely and gave a single F21 error code. Having unplugged the unit and opening the drain at the bottom, I ran the clean cycle again with water only. Finally, I put the same wet clothes through a "Normal/Casual" cycle without detergent or other additives. It ran well and on time until the 36 minutes remaining mark, where it tried to drain, stopped with a SD error code and filled up a little, and repeated the SD error code and fill once more. It all ended with another F21 error code.
I am baffled. Could it still be a pump problem? The impellers are not damaged and turn freely when bench tested. Is it the sensor unit itself?
I felt it necessary to give all the details in this lengthy post in order to receive an intelligent response. Does anyone have an idea what is going on?