How to Fix F21 Error Code on a Washer: Drain Failure Guide
Quick Answer
F21 on a washer indicates a long drain error where the machine fails to empty the water within the allotted eight-minute window. This is usually caused by a physical blockage in the drain pump filter, such as coins, socks, or lint, or a failing drain pump motor.
I've seen F21 more times than I can count, and it almost always tells me what was sitting in someone's pockets. Honestly, about 80% of these calls don't need a single part. It's usually a coin trap stuffed with pocket change or a drain hose kinked behind the machine. Ignore it long enough though and your pump burns out trying to force water through a blockage. That's when a free fix turns into a $120 repair.
Here's the deal with F21: your washer's timing out because it can't drain fast enough. The pump's either fighting a clog or it's lost the muscle to push water up the standpipe. I've watched perfectly good pumps get killed because someone let a partial clog sit in the filter for months. In rare cases the pressure switch is just lying to the control board about how much water's left. But start with the filter. It's almost always the filter.
Most Likely Causes
Based on aggregated repair data, here is the probability breakdown for this error code:
Clogged drain pump filter55%
Failed drain pump motor25%
Drain hose restriction10%
Pressure switch or sensor fault7%
Main control board failure3%
Symptoms You May Notice
Washer stops mid-cycle with water still in the drum
The pump makes a loud growling or humming noise
The door remains locked because the water has not drained
The machine takes much longer than usual to finish a cycle
Can you reset a Generic washer to clear the F21 code?
Hit Power or Cancel twice to clear the F21 code. If you've already manually drained the water, pick a new cycle and give the board about 60 seconds to reset completely before you kick it off. If F21 comes right back as soon as the drain cycle starts, the board's still detecting a fault and you haven't fixed the root problem yet.
Tools Required for Diagnosis
Phillips #2 screwdriverQuarter-inch nut driverDigital multimeter (set to ohms)Shallow baking pan or cookie sheetOld towels or rags (several)Needle-nose pliersFlashlight or headlamp
Service / Diagnostic Mode
With the washer in standby, press any three buttons (except Power or Start) in a 1-2-3, 1-2-3, 1-2-3 sequence. All LEDs will light up, and you can rotate the dial to view the last saved error codes.
Diagnostic Checklist
Follow these steps in order. We start with the easiest external fixes before opening up the machine.
ComponentComponent Under Test
Expected Range10–25 ohms
ConditionIf Open (OL) or infinite, replace component.
Replacement Parts
If your diagnostic testing proves the component has failed, you will need a replacement. We recommend OEM parts over aftermarket for water-handling components.
Part Name
OEM Number
Estimated Price
Drain Pump AssemblyWPW10730972 · $45–$120
WPW10730972
$45 – $120
Frequently Asked Questions
Why does my washer only show F21 during the final spin?
The final spin is when your washer needs to dump the most water the fastest. If your pump's weak or the filter's half-clogged, it might actually keep up during the early rinses but totally choke when the spin cycle ramps up and demands full flow. Honestly this is one of my favorite symptoms because it's a dead giveaway. Either the pump's starting to fail, the filter's nearly full, or you've got a partial clog somewhere downstream. Start with the filter. It's almost always the filter.
Can I bypass the F21 code to get my clothes out?
You can't bypass it, but you can still get your clothes out. Lower the drain hose into a bucket on the floor and let gravity pull the water out, or slowly crack open the pump filter cap and let it drain into towels. Once the water's gone, the door lock should release on its own in a few minutes. If it doesn't release, there's a manual release tab behind the lower toe panel, usually a small plastic loop you pull toward you. Grab a flashlight and look for it near the door lock assembly.
Will using too much soap cause an F21 error?
Yeah it can, and it's way more common than people think. Too much detergent creates a ton of suds and suds are mostly air. Your drain pump can't move air the same way it moves water, so it just spins and spins without actually draining anything out. This is called air-locking. If you're seeing a lot of foam in the drum, run a Rinse and Spin cycle with zero detergent and see if the code clears. Also if you're not using HE detergent in a front-loader, that's probably your whole problem right there.
Is it worth repairing an older washer with an F21 code?
Almost always yes. F21's one of the best codes to get because it's rarely catastrophic. A new drain pump runs $60-120 depending on your model, and it's about a two-hour job once you've done it before. Compare that to $800+ for a new machine. The only time I'd say skip it is if the machine already has major rust on the drum, a loud banging during spin that means a bad bearing, or it's 15-plus years old and this is the third repair in two years. Otherwise, fix it.
How often should I clean the drain pump filter?
Every three to six months if you're running a normal household. Got pets or kids? Do it every two months. Most people never clean it until they get an F21, which is usually way too late and the pump's already been overworked for a long time. It's a five-minute job once you know where the access panel is. Some models have a little drain tube right next to the filter cap so you can empty the water first without making a huge mess. Build it into your routine and you'll probably never see F21 again.