Whirlpool F21 Error Code
F21 on a Whirlpool washer is a drain fault: the machine expected the tub to empty within a set time and it didn't. Nine times out of ten it's a clogged pump filter or drain hose, not a broken part.
F21
Means: Long drain — the washer took longer than expected to pump the water out (front-loaders may show F02 for the same fault).
Fix: Clean the drain pump filter behind the lower front panel, then check the drain hose for kinks or clogs. Restart on a rinse/spin cycle to confirm.
What causes a Whirlpool F21
F21 is triggered when the pressure sensor still sees water after the drain time runs out. In order of likelihood:
- Clogged pump filter (coin trap): socks, coins, hairpins and lint collect here first. This is the #1 cause.
- Kinked or blocked drain hose: a hose pushed too far into the standpipe, kinked behind the machine, or clogged with sludge.
- Clogged household drain / standpipe: if the water backs up, the washer reads it as a slow drain.
- Failing drain pump: if the filter and hose are clear and it still throws F21, the pump impeller or motor is likely worn.
Step-by-step fix
- Turn the washer off and unplug it. Have towels and a shallow tray ready — water will spill.
- Open the small access panel at the lower-right front. Unscrew the round filter cap slowly to release water.
- Pull out the filter, remove any debris, and rinse it under a tap. Check the cavity for a stuck coin.
- Pull the machine out and inspect the drain hose: straighten any kinks and make sure it's not inserted more than a few inches into the standpipe.
- Flush the hose with hot water if it's slow. Reconnect, restore power, and run a rinse+spin to confirm F21 is gone.
When to call a technician
If the filter and hose are clean and F21 keeps returning, the drain pump or the main control board (CCU) may be at fault. A pump swap is a moderate DIY job; a board fault usually means a service call.
FAQ
Is F21 the same as F02 on a Whirlpool washer?
Yes — they report the same long-drain condition. F21 shows on many top and front loaders; F02 appears on some front-load models. The fix is identical: clear the pump filter and drain hose.
How do I clear the F21 code after cleaning the filter?
Restore power and start a rinse/spin cycle. If the water now drains within a couple of minutes, the code clears itself. You can also unplug the washer for one minute to reset the control.
Can too much detergent cause F21?
Indirectly, yes. Excess or non-HE detergent creates suds that slow the pump and can trigger both Sud and F21. Switch to HE detergent and use less.