Whirlpool washer — Error Code F21
Long drain fault; the washer took over 8 minutes to empty.
What it means
The F21 error code on a Whirlpool washer indicates a 'Long Drain' condition. The Central Control Unit (CCU) monitors the water level via the pressure switch. When the drain cycle initiates, the CCU expects the pressure switch to register an empty tub within 8 minutes. If the water level does not drop below the reset threshold in that timeframe, the CCU shuts off the water valves, halts the cycle, and flags F21. On some Whirlpool models, an 'Sd' (suds) error may flash after 4 minutes before the F21 triggers. This is a protective measure to prevent flooding and drain pump motor burnout. The fault lies either in a physical restriction preventing water flow, a mechanical failure of the drain pump, or a sensor failure where the pressure switch fails to recognize that the tub is actually empty.
Likely Causes
- 1 Clogged Drain Pump Filter (Coin Trap)Debris, lint, coins, or small garments are blocking the pump impeller inside the lower filter housing.
- 2 Failed Drain Pump MotorThe pump motor windings are open or shorted, or the impeller has sheared off the motor shaft, preventing water evacuation.
- 3 Blockage in Drain Hose or PlumbingKinks in the external drain hose, clogs in the corrugated tubing, or a backed-up house standpipe preventing water exit.
- 4 Faulty Pressure Switch or Air TubeDebris in the air dome hose or a failed diaphragm in the pressure switch keeps the sensor stuck in the 'full' state even if the tub is empty.
- 5 Wiring or CCU FailureLoss of continuity in the wire harness between the drain pump and the CCU, or a burned drain relay on the main control board.
How to clear / reset
To temporarily clear the F21 code, press the Pause/Cancel button twice. You can also perform a hard reset by unplugging the washer for 1 minute to reset the CCU. However, clearing the code will not fix the underlying issue. If the tub is still full of water, you must manually drain it (using the drain hose or the manual drain tube near the coin trap) before opening the filter housing. The F21 code will immediately return on the next cycle if the physical blockage or pump failure is not resolved.
Common replacement parts
Source: OEM Service Manual
When to call a pro
Call a professional if you have cleared the accessible drain filter (coin trap) and the washer still refuses to drain. Diagnosing a dead drain pump requires a multimeter to check for 120V AC at the pump terminals and verifying winding resistance (usually around 12-15 ohms). If the pump tests good, the issue may be a clogged tub-to-pump boot or a failed CCU relay. Axis Appliance Repair offers a $90 diagnostic (waived on authorized repair) and backs all work with a 1-year parts and labor warranty.
FAQs
How much does it cost to fix an F21 error?
If it's just a clogged filter, it costs nothing to clean it out. If the drain pump needs replacement, expect repairs to range from $150 to $280 including parts and labor.
Can I fix the F21 code myself?
Yes, if the issue is a clogged coin trap. Access the lower front panel, place a shallow pan to catch water, unscrew the filter, and remove any debris. If the pump is dead, it requires part replacement and electrical testing.
Will the F21 code clear itself once the water drains?
No. You must manually clear the code by pressing Pause/Cancel twice or power cycling the machine. The CCU requires a manual reset after a hard fault.
How long does it take a technician to fix this?
A standard drain pump replacement or deep clog removal typically takes 30 to 45 minutes once the technician is on site.
Is it safe to run the washer if it occasionally throws an F21?
No. Forcing the washer to run with intermittent drain issues will overwork the drain pump motor, potentially causing it to short out and damage the main control board (CCU).
Need help with F21?
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