Ronald P Escondido , CA September 12, 2014 Appliance: Model KENMORE HE3T STEAM Sud and f21 errors Cleaned the drain, flushed the soap dispenser, tub and drain lines, didn't fix it. Replaced the pressure switch, didn't fix it. Replaced the CCU and everything is back to normal. 1 People found this story helpful Do-It-Yourself Rating: Repair Time Estimate: 1-2 hours