Answer to: Continuing error codes Sud and F21 after trouble shootingWe just dealt with this today. Cleaned out the trap (which was absolutely clogged) and happily put the washer back together, only to get the same friggin code the next use. We took the front apart again, and water came pouring out, so it wasn't anything there. We just took the drain line off the back of the unit and found standing water in the line. There was no water going through the line so there was a clog somewhere in. We eventually got the line cleared and water flowing through at a good rate. We're crossing our fingers that this is it, because if it isn't I'm about to go out of my mind. So far so good no, annoying beep. SUCCESS!!