Whirlpool washer — Error Code F21
Long drain issue; the appliance failed to empty within an 8-minute window.
What it means
The F21 error denotes a 'Long Drain' scenario. The Central Control Unit (CCU) tracks water levels via the pressure switch. Once a drain cycle starts, the CCU expects the tub to register as empty within 8 minutes. If the water level remains above the threshold after this time, the CCU stops the cycle, closes the water valves, and displays F21. Some units may show an 'Sd' (suds) notification after 4 minutes before the F21 appears. This safety logic prevents flooding and keeps the drain pump motor from burning out. The fault usually stems from a physical obstruction, a mechanical drain pump failure, or a sensor error where the pressure switch cannot detect that the tub has emptied.
Likely Causes
- 1 Clogged Drain Pump Filter (Coin Trap)Small items like coins, lint, or fabric scraps are obstructing the pump impeller inside the lower filter housing.
- 2 Failed Drain Pump MotorThe motor windings are either open or shorted, or the impeller has broken off the shaft, preventing water from moving out.
- 3 Blockage in Drain Hose or PlumbingKinks in the discharge hose, debris in the corrugated tubing, or a congested house standpipe are stopping water flow.
- 4 Faulty Pressure Switch or Air TubeDebris lodged in the air dome hose or a failed diaphragm inside the pressure switch keeps the sensor stuck in a 'full' state even when the tub is empty.
- 5 Wiring or CCU FailureThe wire harness between the drain pump and the CCU has lost continuity, or a drain relay on the main control board has burned out.
How to clear / reset
To reset the F21 code temporarily, press the Pause/Cancel button twice. Alternatively, perform a hard reset by unplugging the unit for 60 seconds to clear the CCU memory. Note that this does not resolve the root cause. If the drum is still full, you must manually drain the water using the drain hose or the manual tube located near the coin trap before attempting to open the filter housing. If the obstruction or pump failure persists, the F21 code will reappear during the next wash cycle.
Common replacement parts
Source: OEM Service Manual
- Tech Sheet - W10071760 - Rev B, p.3
- Tech Sheet - W10005740 - Rev A, p.3
- Tech Sheet - W10117378 - Rev A, p.3
When to call a pro
Contact us if you have cleaned the coin trap and the washer still fails to drain. Diagnosing a faulty drain pump involves using a multimeter to confirm 120V AC at the pump terminals and checking for winding resistance, which should typically be 12-15 ohms. If the pump is functional, the problem might be a clogged tub-to-pump boot or a failed CCU relay. A-Fix Service provides a $90 diagnostic fee (waived if you authorize the repair) and includes a 1-year warranty on parts and labor.
FAQs
What is the typical cost to repair an F21 error?
Cleaning a clogged filter is free if you do it yourself. If the drain pump requires replacement, you can expect costs between $150 and $280 for parts and labor.
Is it possible to resolve the F21 code on my own?
Yes, if the issue is just a blocked coin trap. You can access the lower front panel, use a shallow pan to collect excess water, unscrew the filter, and remove any debris. If the pump is faulty, it will need to be replaced and tested electrically.
Does the F21 code vanish once the water is removed?
No. You must perform a manual reset by pressing Pause/Cancel twice or power cycling the machine, as the CCU requires a manual reset after this type of fault.
How long does a service visit usually take?
Once our technician arrives, a standard pump replacement or clearing a deep clog usually takes between 30 and 45 minutes.
Can I keep using my washer if it shows the F21 code occasionally?
No. Running the washer with intermittent drainage problems puts excessive strain on the drain pump motor, which can cause it to short out or damage your main control board (CCU).
Need help with F21?
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