Whirlpool and Maytag separately identify F21 as a drainage warning on the front loaders described by their support articles. A drain warning is not a failed-pump diagnosis.
Confirm the brand, model and retained water
Do not open a door or filter cap into retained water. Water can be hot. Stop for escaping water or electrical warning signs and avoid wet electrical connections.
Copy F21 exactly and record the full model. This page covers the named front-load references. It does not decode F21 on every brand or appliance type.
Choose the drainage observation
Water remains inside
Record the stage where operation stopped. Look at the visible drain-hose route without disconnecting it. Compare accessible routing with the installation instructions. A hidden restriction remains unchecked.
Water has drained, but F21 appeared during the cycle
Record whether draining was slow and whether excessive suds were visible. Whirlpool’s F21/F02 reference includes detergent among its checks. Keep that alternative separate from an assumed pump failure.
The hose looks normal and the warning returns
Arrange model-specific diagnosis. A humming or silent pump alone does not identify the failing part. Ask the technician which finding distinguishes obstruction, pumping failure and a sensing problem.
A cleared warning is only one result
Both checked references describe a five-minute power interruption as a control-reset option. Confirm your model’s instructions and safe access first. Record separately whether the display cleared and whether normal drainage returned. Repeated resetting is not a repair for a continuing restriction.
Keep the next step model-based
Use the exact instructions for cooling, isolation and controlled draining before filter maintenance. Do not copy a generic pump location, hose height or pressure-switch test. Any replacement still needs a verified full-model part match.
Sources and applicability
- Whirlpool: What is an F21 or F02 Error Code on a Front Load Washer. Drain times; Removing the Error; hose and HE detergent. General Whirlpool front-load reference; F21/F02 grouping in this article only.
- Maytag: F21 – Front Load Washer. F21 Error Code; Cycle power to the control. General Maytag front-load reference; independent confirmation for this brand.
Reviewed October 15, 2026. The references establish the stated general support categories. Exact-model internal tests and replacement-part fitment are not established here.