Our frigidaire front loading washer is not

If your washer isn't draining properly, it's probably giving you the F-21 code. This could be a broken pump or some stuff in the pump or drain hoses. I had this problem last week and I fixed it myself with a pair of pliers and a torque and phillips head screwdrivers.

If there is water coming out of the drain hose when it's running, then the pump is working. (The drain hose is the thing that comes off the back left corner and runs to an inlet against your wall.)

Unplug the machine and turn off, then detach, the hot and cold water hoses.

To clean the pump and drain hoses, you will need to take the back and top off. Very easy, just lots of unscrewing with the torque screwdriver. Have a little bowl handy for the screws. Then tip the machine forward, lid side down.

If the drain hoses are translucent, as mine are, you can see if they have gack in them. Unclamp them with the pliers. (Squeeze the things together and slide the clamp back up the hose it's holding on.) I had lots of gack (we're dairy farmers) and cleaned them with an unbent coat hanger with a piece of rag crimped on one end (use the pliers). There is a hose outside the machine and another one inside the machine. I also cleaned the elbow between them.

The two things inside the machine that you should clean are the rubber funnel that first takes water out of the drum (mine was black) and the pump it attaches to. These hose clamps were especially easy to unclamp. Take the funnel to the sink and wash it with hot water. The pump attaches to the bottom of the washer with red rubber seats. They are very easy to detach. Then you can take the light-tan pump on the left off the motor with the Philips screwdriver. Take the pump to the sink and clean it out. Mine had nails and stuff in it.

Then put it all back together.

This took me about two hours, during which time I felt tough and powerful.

pump failure is not common!! however, remembering to remove objects from our pockets, or washing stringy stuff like rag rugs, or cutoffs with fringe, etc is common..
foreign material will wind itself around the armature of the motor causing noises and poor pumping performance.
you can access the pump by removing the kick plate below the door. if you are so inclined you could remove the pump and check for and correct any blockages or other troubles that can be removed.
however if the pump does need replacement its not a tough job, just cumbersome and time consuming to keep it neat for the customers sake.
137108100 - PUMP-WATER about $90 depending on where you look..
hope this helps,
best of luck,
ttfn