My duet whirlpool front load washer will not drain .error code F21 how do I check to see if something is plugging drain like socks or coins etc.
Take off the lower front panel and you will find access to the pump including a clean out valve.
After you clean it out, unplug the washer for an hour or so to see if that will clear the error code.
Thanks for your reply … I took off the front panel and removed one end of the hose at the pump and low and behold a sock was completely sucked into the pump.ot it out without any problem,thanks ,I know from now on what to look for … 
We always wondered where those socks went.
Glad you got it going and thanks for the update.