The F21 error code indicates the washer is not draining properly. This can be because of a clog in the drain system, faulty drain pump, or improper communication between the draining system and main control board. These issues slow down or completely stop the draining process. Here is a list of the most common causes:
- A lint has stuck inside the drain hose, or the hose is kinked or constricted.
- Blocked/clogged drain filter.
- Blocked or damaged washer drain pump.
- Faulty drain pump. Not unlikely, it needs to be replaced.
Cleaning the pump
- Disconnect the washer from the mains and remove all water from the machine to avoid electrocution.
- Undo the three screws holding the bottom panel and remove it.
- Remove the screws/rubber feet and pull out the tray; place it at the bottom of the machine to avoid flooding.
- Place a handful of rags and towels beneath the drain and prepare buckets and/tubs: there will be a good amount of water coming out. The smell can be nauseating, so breathe through the mouth.
- Remove the goo from the system, put it in a trash can, close the lid and take it out ASAP. Clean the filter and other parts thoroughly.
- Check all connecting tubes for goo and debris using a flashlight. Make sure that the filter area and tube that leads to the pump are clean.
- Place the filter back and be sure it sits correctly. At this point, you can start breathing through the nose.
- Put the washer and instruments back and take a good shower or bath.
Although the procedure is far from pleasure cruise, it is a must-do thing. Most users say their washers work like clock after it, and there are no draining problems. If carried out calmly and consecutively, the procedure takes about 20 minutes.