Product review (5 stars): F21 error is GONE!  powerful motor!
Perfect solution for my dreaded F21 error.  I purchased&nbsp;<a data-hook="product-link-linked" class="a-link-normal" href="/Supco-LP30913-Washer-Drain-Pump/dp/B00RY3AOJ8/ref=cm_cr_arp_d_rvw_txt?ie=UTF8">Supco LP30913 Washer Drain Pump</a>&nbsp;about a year ago, but it didn't fix the intermittent F21 issue.  I kept troubleshooting the other parts, to no avail.
I purchased this pump, and it overloaded my drain.  This pump was powerful enough to show me that I had a partial blockage after the J pipe.
I am super grateful for this pump, I was ready to toss another $1000 plus for another washer after a year of troubleshooting.
Also, before when my washer was done, I could assume that my dryer was also done.  Now my washer completes it's cycle a good 20 minutes before the clothes are dry.